gamma-aminobutyric acid and Diabetic Neuropathies

gamma-aminobutyric acid has been researched along with Diabetic Neuropathies in 209 studies

gamma-Aminobutyric Acid: The most common inhibitory neurotransmitter in the central nervous system.
gamma-aminobutyric acid : A gamma-amino acid that is butanoic acid with the amino substituent located at C-4.

Diabetic Neuropathies: Peripheral, autonomic, and cranial nerve disorders that are associated with DIABETES MELLITUS. These conditions usually result from diabetic microvascular injury involving small blood vessels that supply nerves (VASA NERVORUM). Relatively common conditions which may be associated with diabetic neuropathy include third nerve palsy (see OCULOMOTOR NERVE DISEASES); MONONEUROPATHY; mononeuropathy multiplex; diabetic amyotrophy; a painful POLYNEUROPATHY; autonomic neuropathy; and thoracoabdominal neuropathy. (From Adams et al., Principles of Neurology, 6th ed, p1325)

Research

Studies (209)

Authors

Clinical Trials (36)

Trial Overview

Trial Outcomes

Change From Baseline at Week 1 in Mean Weekly Pain Scores

"The mean change from baseline in mean weekly pain score from daily pain diary using the 11-point numerical rating scale 0(no pain) to 10(worst possible pain) at Week 1.~Change from baseline: Score at Week 1 minus score at baseline" (NCT00553475)
Timeframe: From baseline to Week 1

Change From Baseline at Week 10 in Mean Weekly Pain Scores

"The mean change from baseline in mean weekly pain score from daily pain diary using the 11-point numerical rating scale 0(no pain) to 10(worst possible pain) at Week 10.~Change from baseline: Score at Week 10 minus score at baseline" (NCT00553475)
Timeframe: From baseline to Week 10

Change From Baseline at Week 11 in Mean Weekly Pain Scores

"The mean change from baseline in mean weekly pain score from daily pain diary using the 11-point numerical rating scale 0(no pain) to 10(worst possible pain) at Week 11.~Change from baseline: Score at Week 11 minus score at baseline" (NCT00553475)
Timeframe: From baseline to Week 11

Change From Baseline at Week 12 in Mean Weekly Pain Scores

"The mean change from baseline in mean weekly pain score from daily pain diary using the 11-point numerical rating scale 0(no pain) to 10(worst possible pain) at Week 12.~Change from baseline: Score at Week 12 minus score at baseline" (NCT00553475)
Timeframe: From baseline to Week 12

Change From Baseline at Week 13 in Mean Weekly Pain Scores

"The mean change from baseline in mean weekly pain score from daily pain diary using the 11-point numerical rating scale 0(no pain) to 10(worst possible pain) at Week 13.~Change from baseline: Score at Week 13 minus score at baseline" (NCT00553475)
Timeframe: From baseline to Week 13

Change From Baseline at Week 2 in Mean Weekly Pain Scores

"The mean change from baseline in mean weekly pain score from daily pain diary using the 11-point numerical rating scale 0(no pain) to 10(worst possible pain) at Week 2.~Change from baseline: Score at Week 2 minus score at baseline" (NCT00553475)
Timeframe: From baseline to Week 2

Change From Baseline at Week 3 in Mean Weekly Pain Scores

"The mean change from baseline in mean weekly pain score from daily pain diary using the 11-point numerical rating scale 0(no pain) to 10(worst possible pain) at Week 3.~Change from baseline: Score at Week 3 minus score at baseline" (NCT00553475)
Timeframe: From baseline to Week 3

Change From Baseline at Week 4 in Mean Weekly Pain Scores

"The mean change from baseline in mean weekly pain score from daily pain diary using the 11-point numerical rating scale 0(no pain) to 10(worst possible pain) at Week 4.~Change from baseline: Score at Week 4 minus score at baseline" (NCT00553475)
Timeframe: From baseline to Week 4

Change From Baseline at Week 5 in Mean Weekly Pain Scores

"The mean change from baseline in mean weekly pain score from daily pain diary using the 11-point numerical rating scale 0(no pain) to 10(worst possible pain) at Week 5.~Change from baseline: Score at Week 5 minus score at baseline" (NCT00553475)
Timeframe: From baseline to Week 5

Change From Baseline at Week 6 in Mean Weekly Pain Scores

"The mean change from baseline in mean weekly pain score from daily pain diary using the 11-point numerical rating scale 0(no pain) to 10(worst possible pain) at Week 6.~Change from baseline: Score at Week 6 minus score at baseline" (NCT00553475)
Timeframe: From baseline to Week 6

Change From Baseline at Week 7 in Mean Weekly Pain Scores

"The mean change from baseline in mean weekly pain score from daily pain diary using the 11-point numerical rating scale 0(no pain) to 10(worst possible pain) at Week 7.~Change from baseline: Score at Week 7 minus score at baseline" (NCT00553475)
Timeframe: From baseline to Week 7

Change From Baseline at Week 8 in Mean Weekly Pain Scores

"The mean change from baseline in mean weekly pain score from daily pain diary using the 11-point numerical rating scale 0(no pain) to 10(worst possible pain) at Week 8.~Change from baseline: Score at Week 8 minus score at baseline" (NCT00553475)
Timeframe: From baseline to Week 8

Change From Baseline at Week 9 in Mean Weekly Pain Scores

"The mean change from baseline in mean weekly pain score from daily pain diary using the 11-point numerical rating scale 0(no pain) to 10(worst possible pain) at Week 9.~Change from baseline: Score at Week 9 minus score at baseline" (NCT00553475)
Timeframe: From baseline to Week 9

Change From Baseline in Mean Sleep Interference Scores

The mean change from baseline in the weekly mean sleep interference score at study endpoint. Score range is from 0-10. Higher scores indicate more severe interference with sleep. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Medical Outcomes Study (MOS) - Sleep Scale: Overall Sleep Problems Index

The mean change from baseline in Medical Outcomes Study - Sleep Scale Scores at study endpoint. Score for overall sleep problems index ranges from 0-100. Higher scores indicate more of the attribute. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Medical Outcomes Study (MOS) - Sleep Scale: Quantity of Sleep

The mean change from baseline in Medical Outcomes Study - Sleep Scale Scores at study endpoint. Score for quantity of sleep ranges from 0-24. Higher scores indicate more of the attribute named in the subscale. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Medical Outcomes Study (MOS) - Sleep Scale: Sleep Adequacy

The mean change from baseline in Medical Outcomes Study - Sleep Scale Scores at study endpoint. Score for sleep adequacy ranges from 0-100. Higher scores indicate more of the attribute. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Medical Outcomes Study (MOS) - Sleep Scale: Sleep Disturbance

The mean change from baseline in Medical Outcomes Study - Sleep Scale Scores at study endpoint. Score for sleep disturbance ranges from 0-100. Higher scores indicate more severe pain. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Medical Outcomes Study (MOS) - Sleep Scale: Sleep Shortness of Breath or Headache

The mean change from baseline in Medical Outcomes Study - Sleep Scale Scores at study endpoint. Score for sleep shortness of breath or headache ranges from 0-100. Higher scores indicate more of the attribute. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Medical Outcomes Study (MOS) - Sleep Scale: Snoring

The mean change from baseline in Medical Outcomes Study - Sleep Scale Scores at study endpoint. Score for snoring ranges from 0-100. Higher scores indicate more of the attribute. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Medical Outcomes Study (MOS) - Sleep Scale: Somnolence

The mean change from baseline in Medical Outcomes Study - Sleep Scale Scores at study endpoint. Score for somnolence ranges from 0-100. Higher scores indicate more of the attribute. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Short Form 36-Item (SF-36) Health Survey: Bodily Pain

The mean change from baseline in Short-Form 36-Item Health Survey Scores at study endpoint. Short-Form 36-Item Health Survey is scored from 0-100 with higher scores reflecting better patient status. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Short Form 36-Item (SF-36) Health Survey: General Health Perception

The mean change from baseline in Short-Form 36-Item Health Survey Scores at study endpoint. Short-Form 36-Item Health Survey is scored from 0-100 with higher scores reflecting better patient status. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Short Form 36-Item (SF-36) Health Survey: Mental Health

The mean change from baseline in Short-Form 36-Item Health Survey Scores at study endpoint. Short-Form 36-Item Health Survey is scored from 0-100 with higher scores reflecting better patient status. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Short Form 36-Item (SF-36) Health Survey: Physical Functioning

The mean change from baseline in Short-Form 36-Item Health Survey Scores at study endpoint. Short-Form 36-Item Health Survey is scored from 0-100 with higher scores reflecting better patient status. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Short Form 36-Item (SF-36) Health Survey: Role Limitations-Emotional

The mean change from baseline in Short-Form 36-Item Health Survey Scores at study endpoint. Short-Form 36-Item Health Survey is scored from 0-100 with higher scores reflecting better patient status. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Short Form 36-Item (SF-36) Health Survey: Role Limitations-Physical

The mean change from baseline in Short-Form 36-Item Health Survey Scores at study endpoint. Short-Form 36-Item Health Survey is scored from 0-100 with higher scores reflecting better patient status. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Short Form 36-Item (SF-36) Health Survey: Social Functioning

The mean change from baseline in Short-Form 36-Item Health Survey Scores at study endpoint. Short-Form 36-Item Health Survey is scored from 0-100 with higher scores reflecting better patient status. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Short Form 36-Item (SF-36) Health Survey: Vitality

The mean change from baseline in Short-Form 36-Item Health Survey Scores at study endpoint. Short-Form 36-Item Health Survey is scored from 0-100 with higher scores reflecting better patient status. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Short-Form McGill Pain Questionnaire: Affective Scores

The mean change from baseline in Short-Form McGill Pain Questionnaire Scores at study endpoint. Affective score ranges from 0-12. Higher scores indicate more severe pain. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Short-Form McGill Pain Questionnaire: Present Pain Intensity Scores

The mean change from baseline in Short-Form McGill Pain Questionnaire Scores at study endpoint. Present pain intensity score ranges from 0-5. Higher scores indicate more severe pain. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Short-Form McGill Pain Questionnaire: Sensory Scores

The mean change from baseline in Short-Form McGill Pain Questionnaire Scores at study endpoint. Sensory score ranges from 0-33. Higher scores indicate more severe pain. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Short-Form McGill Pain Questionnaire: Total Scores

The mean change from baseline in Short-Form McGill Pain Questionnaire Scores at study endpoint. Total score ranges from 0-45. Higher scores indicate more severe pain. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline in Short-Form McGill Pain Questionnaire: Visual Analogue Scale Scores

The mean change from baseline in Short-Form McGill Pain Questionnaire Scores at study endpoint. Visual Analogue Scale Score ranges from 0-100 mm. Higher scores indicate more severe pain. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline to Study Endpoint in Mean Weekly Pain Scores

Change from baseline: Score at study endpoint minus score at baseline. Study endpoint is defined as the mean of the last seven entries of the daily pain diary using the 11-point numerical rating scale 0(no pain) to 10(worst possible pain) while on study medication up to and including day after last dose. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Change From Baseline to Study Endpoint in Mean Weekly Pain Scores by Groups of Subjects With Expected Similar Plasma Concentrations

Change from baseline: Score at study endpoint minus score at baseline. Study endpoint is defined as the mean of the last seven entries of the daily pain diary using the 11-point numerical rating scale 0(no pain) to 10(worst possible pain) while on study medication up to and including day after last dose. Subjects are classified by exposure to pregabalin, which is estimated by creatinine clearance (CLcr). (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Clinical Global Impression of Change

Clinical Global Impression of Change is a clinician-rated instrument that measures change in patient's overall status on a 7-point scale ranging from 1 (very much improved) to 7 (very much worse). (NCT00553475)
Timeframe: Week 13 or up to discontinuation

Number of Responders

A responder is defined as a subject with a 50% reduction in weekly mean pain score from baseline to study endpoint. (NCT00553475)
Timeframe: From baseline to Week 13 or up to study discontinuation (Study Endpoint)

Patient Global Impression of Change

The Patient Global Impression of Change is a patient-rated instrument that measures change in patient's overall status on a 7-point scale ranging from 1 (very much improved) to 7 (very much worse). (NCT00553475)
Timeframe: Week 13 or up to discontinuation

Endpoint Mean Sleep Interference Score (Double-Blind Phase)

Endpoint mean sleep interference score was defined as the mean of the last 7 sleep interference diaries while receiving DB treatment. Participants rated how painful DPN has interfered with their sleep during the past 24 hours on an 11-point numeric rating scale ranging from 0 = does not interfere to 10 = completely interferes (unable to sleep due to pain). (NCT01057693)
Timeframe: Week 19

Endpoint Mean Sleep Interference Score (Single-Blind Phase)

Endpoint mean sleep interference score was defined as the mean of the last 7 sleep interference diaries while receiving SB treatment. Participants rated how painful DPN has interfered with their sleep during the past 24 hours on an 11-point numeric rating scale ranging from 0 = does not interfere to 10 = completely interferes (unable to sleep due to pain). (NCT01057693)
Timeframe: Week 6

Number of Participants With Optimal Sleep Assessed Using Medical Outcomes Study-Sleep Scale (MOS-SS) (Double-Blind Phase)

MOS-SS: participant-rated 12 item questionnaire to assess constructs of sleep over past week. It included 7 subscales: sleep disturbance, snoring, awaken short of breath or with headache, sleep adequacy, somnolence, sleep quantity, optimal sleep, and 9 item index measures of sleep disturbance provide composite scores: sleep problems index. Participants responded whether their sleep was optimal or not optimal by choosing yes or no. (NCT01057693)
Timeframe: Week 19

Pain Visual Analog Scale (VAS) (Double-Blind Phase)

Participants rated their pain on a 100 millimeter (mm) Visual Analog Scale (VAS) ranging from 0 mm = no pain to 100 mm = worst possible pain. (NCT01057693)
Timeframe: Week 19

Time to Loss of Pain Response (Double-Blind Phase)

Time to loss of pain response (based on the daily pain diary data) during the DB treatment phase was analyzed using survival analysis technique. Loss of pain response was defined as less than (<) 15% pain response relative to the SB baseline. SB baseline refers to the last 7 pain diary entries up to and including Day 1. (NCT01057693)
Timeframe: SB Baseline up to Week 19

Brief Pain Inventory-Short Form (BPI-sf) (Double-Blind Phase)

BPI-sf: self-administered questionnaire developed to assess severity, impact of pain on daily functions, consisted of 5 questions. Questions 1-4 measured the severity of pain based on pain experienced over the past 24-hours on an 11-point scale ranged from 0 (no pain) to10 (worst possible pain). Question 5: 7 item subsets that measured level of interference of pain on daily functions on an 11-point scale ranged from 0 (does not interfere) to 10 (completely interferes). (NCT01057693)
Timeframe: Week 19

Brief Pain Inventory-Short Form (BPI-sf) (Single-Blind Phase)

BPI-sf: self-administered questionnaire developed to assess severity, impact of pain on daily functions, consisted of 5 questions. Questions 1-4 measured the severity of pain based on pain experienced over the past 24-hours on an 11-point scale ranged from 0 (no pain) to10 (worst possible pain). Question 5: 7 item subsets that measured level of interference of pain on daily functions on an 11-point scale ranged from 0 (does not interfere) to 10 (completely interferes). (NCT01057693)
Timeframe: SB Baseline, Week 6

Change From Single-Blind Baseline in Mean Pain Score at Week 19 During Double-Blind Phase

Mean pain score was defined as the mean of the last 7 daily diary pain ratings. Participants rated their DPN pain over the past 24 hours on an 11-point numeric rating scale ranging from 0 = no pain to 10 = worst possible pain. A rating of 1-3 was considered as mild pain; 4-6 = moderate pain; and 7-10 = severe pain. SB baseline refers to the last 7 pain diary entries up to and including Day 1. (NCT01057693)
Timeframe: SB Baseline, Week 19 (DB Phase)

Change From Single-Blind Baseline in Mean Pain Score at Week 6 During Single-Blind Phase

Mean pain score was defined as the mean of the last 7 daily diary pain ratings. Participants rated their DPN pain over the past 24 hours on an 11-point numeric rating scale ranging from 0 = no pain to 10 = worst possible pain. A rating of 1-3 was considered as mild pain; 4-6 = moderate pain; and 7-10 = severe pain. SB baseline refers to the last 7 pain diary entries up to and including Day 1. (NCT01057693)
Timeframe: SB Baseline, Week 6 (SB Phase)

Hospital Anxiety and Depression Scale (HADS) (Double-Blind Phase)

HADS: self-administered questionnaire, consists of 2 sub-scales; measuring anxiety (HADS-A), and depression (HADS-D). Each sub-scale consists of 7 items on which participants responded as to how each item applies to them on a 4-point scale ranging from 0 (no anxiety or depression) to 3 (severe feeling of anxiety or depression). Total score range for each sub-scale = 0 to 21, where higher score indicates more severe anxiety or depression. (NCT01057693)
Timeframe: Week 19

Hospital Anxiety and Depression Scale (HADS) (Single-Blind Phase)

HADS: self-administered questionnaire, consists of 2 sub-scales; measuring anxiety (HADS-A), and depression (HADS-D). Each sub-scale consists of 7 items on which participants responded as to how each item applies to them on a 4-point scale ranging from 0 (no anxiety or depression) to 3 (severe feeling of anxiety or depression). Total score range for each sub-scale = 0 to 21, where higher score indicates more severe anxiety or depression. (NCT01057693)
Timeframe: SB Baseline, Week 6

Medical Outcomes Study -Sleep Scale (MOS-SS) (Double-Blind Phase)

Participant-rated 12-item questionnaire to assess constructs of sleep over past week; 7 subscales: sleep disturbance (range 0-100), snoring (range 0-100), awaken short of breath (SOB) or with headache (range 0-100), sleep adequacy (range 0-100), somnolence (range: 0-100); sleep quantity (range: 0-24), optimal sleep (yes/no), and 9 item index measures of sleep disturbance provide composite scores: sleep problems index (range 0-100). Except adequacy, optimal sleep and quantity, higher scores=more impairment. (NCT01057693)
Timeframe: Week 19

Medical Outcomes Study -Sleep Scale (MOS-SS) (Single-Blind Phase)

Participant-rated 12-item questionnaire to assess constructs of sleep over past week; 7 subscales: sleep disturbance (range 0-100), snoring (range 0-100), awaken short of breath (SOB) or with headache (range 0-100), sleep adequacy (range 0-100), somnolence (range: 0-100); sleep quantity (range: 0-24), optimal sleep (yes/no), and 9 item index measures of sleep disturbance provide composite scores: sleep problems index (range 0-100). Except adequacy, optimal sleep and quantity, higher scores=more impairment. (NCT01057693)
Timeframe: SB Baseline, Week 6

Number of Participants With Optimal Sleep Assessed Using Medical Outcomes Study-Sleep Scale (MOS-SS) (Single-Blind Phase)

MOS-SS: participant-rated 12 item questionnaire to assess constructs of sleep over past week. It included 7 subscales: sleep disturbance, snoring, awaken short of breath or with headache, sleep adequacy, somnolence, sleep quantity, optimal sleep, and 9 item index measures of sleep disturbance provide composite scores: sleep problems index. Participants responded whether their sleep was optimal or not optimal by choosing yes or no. (NCT01057693)
Timeframe: SB Baseline, Week 6

Pain Visual Analog Scale (VAS) (Single-Blind Phase)

Participants rated their pain on a 100 millimeter (mm) Visual Analog Scale (VAS) ranging from 0 mm = no pain to 100 mm = worst possible pain. (NCT01057693)
Timeframe: SB Baseline, Week 6

Patient Global Evaluation of Study Medication (GESM) (Double-Blind Phase)

"GESM: single-item, self-administered treatment satisfaction questionnaire. Participants answered how would you rate the study medication you received for pain? on a 7-point scale ranging from 1 (very satisfied) to 7 (very dissatisfied). Number of participants in each category are reported." (NCT01057693)
Timeframe: Week 19

Patient Global Evaluation of Study Medication (GESM) (Single-Blind Phase)

"GESM: single-item, self-administered treatment satisfaction questionnaire. Participants answered how would you rate the study medication you received for pain? on a 7-point scale ranging from 1 (very satisfied) to 7 (very dissatisfied). Number of participants in each category are reported." (NCT01057693)
Timeframe: Week 6

Patient Global Impression of Change (PGIC) (Double-Blind Phase)

PGIC: participant rated instrument to measure participant's change in overall status on a 7-point scale; range from 1 (very much improved) to 7 (very much worse). Number of participants in each category are reported. (NCT01057693)
Timeframe: Week 19

Patient Global Impression of Change (PGIC) (Single-Blind Phase)

PGIC: participant rated instrument to measure participant's change in overall status on a 7-point scale; range from 1 (very much improved) to 7 (very much worse). Number of participants in each category are reported. (NCT01057693)
Timeframe: Week 6

Percentage of Participants With At Least 30 Percent and 50 Percent Reduction in Mean Pain Score (Double-Blind Phase)

Mean pain score was defined as the mean of the last 7 daily diary pain ratings. Participants rated their DPN pain over the past 24 hours on an 11-point numeric rating scale ranging from 0 = no pain to 10 = worst possible pain. A rating of 1-3 was considered as mild pain; 4-6 = moderate pain; and 7-10 = severe pain. Percentage of participants who had at least 30% and 50% pain reduction from SB baseline to Week 19 is reported. (NCT01057693)
Timeframe: Week 19

Percentage of Participants With At Least 30 Percent and 50 Percent Reduction in Mean Pain Score (Single-Blind Phase)

Mean pain score was defined as the mean of the last 7 daily diary pain ratings. Participants rated their DPN pain over the past 24 hours on an 11-point numeric rating scale ranging from 0 = no pain to 10 = worst possible pain. A rating of 1-3 was considered as mild pain; 4-6 = moderate pain; and 7-10 = severe pain. Percentage of participants who had at least 30% and 50% pain reduction from SB baseline to Week 6 is reported. SB baseline refers to the last 7 pain diary entries up to and including Day 1. (NCT01057693)
Timeframe: Week 6

Quality of Life Questionnaire- Diabetic Neuropathy (QOL-DN) (Double-Blind Phase)

QOL-DN: 35-item participant-rated questionnaire used to assess impact of diabetic neuropathy on the quality of life of participants with diabetic neuropathy. Consists of 5 domains: Physical functioning(Ph Fn)/large fiber (sum of item 8, 11, 13-15, 24, 27-35; range -4 to 56); Activities of daily living (sum of item 12, 22, 23, 25, 26; range 0 to 20); Symptoms (sum of item 1-7, 9; range 0 to 32); Small fiber (sum of item 10, 16, 17, 18; range 0 to 16); Autonomic (sum of item 19, 20, 21; range 0 to 12) and total QOL score (sum of items 1-35) range: -4 to 136. Higher score implied worse QOL. (NCT01057693)
Timeframe: Week 19

Quality of Life Questionnaire- Diabetic Neuropathy (QOL-DN) (Single-Blind Phase)

QOL-DN: 35-item participant-rated questionnaire used to assess impact of diabetic neuropathy on the quality of life of participants with diabetic neuropathy. Consists of 5 domains: Physical functioning(Ph Fn)/large fiber (sum of item 8, 11, 13-15, 24, 27-35; range -4 to 56); Activities of daily living (sum of item 12, 22, 23, 25, 26; range 0 to 20); Symptoms (sum of item 1-7, 9; range 0 to 32); Small fiber (sum of item 10, 16, 17, 18; range 0 to 16); Autonomic (sum of item 19, 20, 21; range 0 to 12) and total QOL score (sum of items 1-35) range: -4 to 136. Higher score implied worse QOL. (NCT01057693)
Timeframe: SB Baseline, Week 6

Weekly Mean Pain Scores (Double-Blind Phase)

Weekly mean pain score was defined as the mean of the daily diary pain ratings split into 7 day intervals. Participants rated their DPN pain over the past 24 hours on an 11-point numeric rating scale ranging from 0 = no pain to 10 = worst possible pain. A rating of 1-3 was considered as mild pain; 4-6 = moderate pain; and 7-10 = severe pain. SB baseline refers to the last 7 pain diary entries up to and including Day 1. DB baseline refers to the last 7 pain diary entries up to and including DB Day 1. (NCT01057693)
Timeframe: DB Baseline, Week 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19

Weekly Mean Pain Scores (Single-Blind Phase)

Weekly mean pain score was defined as the mean of the daily diary pain ratings split into 7 day intervals. Participants rated their DPN pain over the past 24 hours on an 11-point numeric rating scale ranging from 0 = no pain to 10 = worst possible pain. A rating of 1-3 was considered as mild pain; 4-6 = moderate pain; and 7-10 = severe pain. (NCT01057693)
Timeframe: Week 1, 2, 3, 4, 5, 6

Weekly Mean Sleep Interference Score (Double-Blind Phase)

Weekly mean sleep interference score was defined as the mean of the daily sleep interference diary ratings split into 7 day intervals. Participants rated how painful DPN has interfered with their sleep during the past 24 hours on an 11-point numeric rating scale ranging from 0 = does not interfere with sleep to 10 = completely interferes (unable to sleep due to pain). (NCT01057693)
Timeframe: DB Baseline, Week 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19

Weekly Mean Sleep Interference Score (Single-Blind Phase)

Weekly mean sleep interference score was defined as the mean of the daily sleep interference diary ratings split into 7 day intervals. Participants rated how painful DPN has interfered with their sleep during the past 24 hours on an 11-point numeric rating scale ranging from 0 = does not interfere with sleep to 10 = completely interferes (unable to sleep due to pain). SB baseline refers to the last 7 pain diary entries up to and including Day 1. (NCT01057693)
Timeframe: SB Baseline, Week 1, 2, 3, 4, 5, 6

2) The Difference in Change Between Quantified Utah Early Neuropathy Examination Scores, Between Treatment and Placebo Groups Between Visits 1 and 8.

"The Utah Early Neuropathy Scale (UENS) was developed specifically to detect and quantify early small-fiber sensory neuropathy and to recognize modest changes in sensory severity and distribution.~The UENS scale ranges from 0 (no neuropathy) to 42 (severe small fiber neuropathy). The outcome measure is the UENS score from Visit 8 minus the UENS score at visit 1. The difference in the two scores indicates the change in neuropathy severity. A positive value indicates that neuropathy has worsened over the course of the study, a negative value indicates that neuropathy has improved over the course of the study." (NCT03401073)
Timeframe: Visit 1 (time zero) and visit 8 (range of visit time 22-27 weeks after visit 1), thus a total of 22-27 weeks for the study (the range is provided to ensure final follow up is completed despite any conflicts with travel or holidays).

The Change in Nerve Fiber Density Between Visits 1 and 8.

"Difference in intra-epidermal nerve fiber density between visits 1 and 8 will be measured.~Intra-epidermal nerve fiber density is a quantitative measure of the number of nerve fibers per millimeter. The outcome is the number of nerve fibers measured at visit 8 minus the number of nerve fibers measured at visit 1. A positive value indicates that nerve fiber density has increased (a better outcome), a negative value indicates that the nerve fiber density has decreased (a worse outcome)." (NCT03401073)
Timeframe: Visit 1 (time zero) and visit 8 (range of visit time 22-27 weeks after visit 1), thus a total of 22-27 weeks for the study (the range is provided to ensure final follow up is completed despite any conflicts with travel or holidays).

The Change in Neuropathic Pain Severity Between Visits 1 and 8.

"The visual analog scale (VAS) of pain allows for quantification of neuropathic pain.~The VAS pain scale depicts a line ranging from 0 (no pain) to 10 (worst possible pain). The scale is ordinal ranging from 0-10.~The difference in pain between visit 1 and visit 8 (pain measured at visit 8 subtracted from the score at visit 1) is the range. Positive values indicate an increase in pain (worse outcome), negative values indicate an improvement in pain (better outcome)." (NCT03401073)
Timeframe: Visit 1 (time zero) and visit 8 (range of visit time 22-27 weeks after visit 1), thus a total of 22-27 weeks for the study (the range is provided to ensure final follow up is completed despite any conflicts with travel or holidays).

Number of Participants With Adverse Events (AEs)

An adverse event (AE) is defined as any untoward medical occurrence in the form of signs, symptoms, abnormal laboratory findings, or diseases that emerges or worsens relative to Baseline during a clinical study with an investigational medicinal product (IMP), regardless of causal relationship and even if no IMP has been administered. (NCT01364298)
Timeframe: Day 7 up to Day 84 (+7 days)

Profile of Mood States (POMS) Score

"POMS is a rating scale, which comprises of 65 items that are evaluated in a 0-4 scale, where 0 means not at all and 4 extremely. The scores for the 65 items are added in various combinations to throw six validated factors which are used to calculate total POMS score: (tension-anxiety) + (depression-dejection) + (anger-hostility)+ (fatigue-Inertia) + (confusion-bewilderment) - (vigor-activity). Score range (-40 to 192). Score -40 denotes the best score and score 192 denotes the worst score." (NCT01364298)
Timeframe: Day 84 (Week 12)

Change From Baseline in Average Numeric Pain Intensity Scale (NPIS) Score at Day 84

An average NPIS pain score (daily average records of the past seven days) was evaluated. Numeric pain intensity scale (NPIS) is a 11-point scale, with 0 representing no pain and 10 representing the worst possible pain. The participants were asked to mark the number that best represents the current level of pain they have experienced during the previous 24 hours. Change from baseline data has been calculated as value at baseline minus value at Day 84. (NCT01364298)
Timeframe: Baseline and Day 84 (Week 12)

Change From Baseline in Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) Scale Score at Day 84

The LANSS scale score is 7-item pain scale that consists of grouped sensory description and sensory examination with simple scoring system. Evaluations in two main areas: pain and sensorial exploration. The first 5 questions asks for presence of unpleasant skin sensations (pricking, tingling, pins and needles), appearance of skin (mottled, red, or pink), increased sensitivity of skin to touch, sudden bursts of electric shock sensations, and hot or burning skin sensations. Last 2 questions involve sensory testing for the presence of allodynia and altered pinprick threshold. Different numbers of points, relative to their significance to neuropathic pain, are given to positive answers for maximum of 24 points. A score less than 12 makes unlikely that participant's symptoms are neuropathic in nature, whereas score more than 12 make neuropathic mechanisms likely to be contributing to participant's pain. Change from baseline data has been calculated as value at baseline minus value at Day 84. (NCT01364298)
Timeframe: Baseline and Day 84 (Week 12)

Change From Baseline in Visual Analogue Scale (VAS) Score at Day 84

VAS is used to rate the pain as per 10 centimeter (cm) line. The pain intensity score ranges from '0=no pain' to '10=worst possible pain'. Change from baseline data has been calculated as value at baseline minus value at Day 84. (NCT01364298)
Timeframe: Baseline and Day 84 (Week 12)

Number of Participants With Various Health Conditions Based on Clinical Global Impression of Change (CGIC) Scale

CGIC is an assessment that the physician performs to assess the participant's global change in health condition from start of the study on a 7-point scale (1 = extremely improved, 2 = much improved, 3 = minimally improved, 4 = no change, 5 = minimally worse 6 = much worse, 7 = extremely worse). (NCT01364298)
Timeframe: Baseline and Day 84 (Week 12)

Number of Participants With Various Health Conditions Based on Global Impression of Patient Change (GIPC) Scale

GIPC is an assessment that the participant's global change in health condition from start of the study on a 7-point scale (1 = extremely improved, 2 = much improved, 3 = minimally improved, 4 = no change, 5 = minimally worse 6 = much worse, 7 = extremely worse). (NCT01364298)
Timeframe: Baseline and Day 84 (Week 12)

Percentage of Participants With at Least 30 and 50 Percent (%) Improvement in Numeric Pain Intensity Scale (NPIS) From Baseline at Day 84 (Week 12)

NPIS is a 11-point scale, with 0 representing no pain and 10 representing the worst possible pain. The participants were asked to mark the number that best represents the current level of pain they have experienced during the previous 24 hours. (NCT01364298)
Timeframe: Baseline and Day 84 (Week 12)

Sleep Evaluation: Number of Participants Who Fell Asleep in Pre-specified Time Duration

Sleep evaluation was performed by assessing number of participants who fell asleep in a particular pre-specified range of time duration, that is, 0-15 minutes, 16-30 minutes, 31-45 minutes, 46-60 minutes and greater than 60 minutes at Day 84 (Week 12). (NCT01364298)
Timeframe: Day 84 (Week 12)

Assessing the Change in Heart Rate by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.

The LifeShirt System, developed by VivoMetrics, is a lightweight vest with embedded sensors that continuously collect information on a range of cardiopulmonary parameters. It was used to collect and store the respiratory rate, posture, activity level, QRS complexes, and R-R intervals via a 3-axis accelerometer and a 3-lead, single channel electrocardiogram. (NCT00573261)
Timeframe: baseline and at end of a 4-week intervention

Assessing the Change of Parameters of Autonomic Nerve Function Such as Heart Rate Variability by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.

Heart rate variability parameters yielded by time domain analysis included the number of N-N intervals that differ by more than 50 milliseconds from adjacent intervals divided by the total number of all N-N intervals (pNN50). (NCT00573261)
Timeframe: baseline and at end of a 4-week intervention

Assessing the Change of Parameters of Autonomic Nerve Function Such as Heart Rate Variability by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.

Heart rate variability parameters yielded by time domain analysis included the number of N-N intervals that differ by more than 50 milliseconds from adjacent intervals divided by the total number of all N-N intervals (pNN50). (NCT00573261)
Timeframe: baseline and at end of a 4-week intervention

To Assess the Change of Depressive Symptoms Upon Treatment of Pregabalin in Comparison to Placebo.

The Beck Depression Inventory Scale measures symptoms of depression, score range, 0-63 (higher score=greater severity of depressive symptoms) (NCT00573261)
Timeframe: baseline and at end of a 4-week intervention

Assessing the Change in Heart Rate Variability by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.

Heart Rate Variability parameters generated by the frequency domain analysis included: Low Frequency / High Frequency (LF/HF), as well as normalized LF (normalized LF=LF/[total power-VLF]) and normalized HF (normalized HF=HF/[total power-VLF]). (NCT00573261)
Timeframe: baseline and at end of a 4-week intervention

Assessing the Change in Heart Rate Variability by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.

Heart rate variability parameters generated by the frequency domain analysis included: total power (area under the curve) over all frequencies, very low frequency (VLF, 0-0.04 Hz),low frequency (LF, 0.04-0.15 Hz), and high frequency (HF,0.15-0.4 Hz). (NCT00573261)
Timeframe: baseline and at end of a 4-week intervention

Assessing the Change in Resting Blood Pressure Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.

(NCT00573261)
Timeframe: baseline and at end of a 4-week intervention

Assessing the Change of Parameters of Autonomic Nerve Function Such as Heart Rate Variability by Means of the LifeShirt System Upon Treatment of Pregabalin vs. Placebo in Patients With Diabetes and Peripheral Neuropathy.

Heart rate variability parameters yielded by time domain analysis included the mean of all R-R intervals (ANN), standard deviation of all R-R intervals (SDNN), root mean square of successive differences (RMSSD), and standard deviation of the averages of R-R intervals for all 5-minute segments within the block (SDANN). (NCT00573261)
Timeframe: baseline and at end of a 4-week intervention

To Assess the Change in Disability Scale Upon Treatment of Pregabalin in Comparison to Placebo.

The Sheehan Disability Scale was used to evaluate functional impairment in work/school, social and family life, score range, 0-10; the 3 items can be summed into a single dimensional measure of global functional impairment that ranges from 0(unimpaired) to 30 (highly impaired). (NCT00573261)
Timeframe: baseline and at end of a 4-week intervention

To Assess the Change of Anxiety Symptoms Upon Treatment of Pregabalin in Comparison to Placebo.

Anxiety symptoms were measured using the Spielberger State-Trait Anxiety Inventory Scale (STAI) for symptoms of anxiety. State anxiety: score range, 20-80 (higher score=greater levels of state anxiety). Trait anxiety: score range, 20-80 (higher score=greater levels of trait anxiety). (NCT00573261)
Timeframe: baseline and at end of a 4-week intervention

To Assess the Change of Pain Symptoms Upon Treatment of Pregabalin in Comparison to Placebo.

Pain severity was evaluated using the Visual Analog Scale, the Modified Brief Pain Inventory-Short Form, and the Neuropathy Pain Scale. The Visual Analog Scale was scored within a range of 0-100 with 0=no pain and 100=the worst imaginable pain. The Brief Pain Inventory is made up of two parts: total pain and pain interference. The total pain score is the sum of most, least, average, and now pain scored within a range of 0-10 with 0=no pain and 10=pain as bad as you can imagine. The pain interference score is the sum of affective and activity interference - how pain interfered with general activity, mood, walking ability, normal work, relationships, sleep, and enjoyment of life. It was scored within a range of 0-10 with 0=pain does not interfere and 10=pain completely interferes. The Neuropathy Pain Scale total is the sum of 10 items -cold, sharp, deep, dull, hot, intense, itchy, sensitive, surface, and unpleasant pain scored within a range of 0-10 with 0=no pain and 10=most pain. (NCT00573261)
Timeframe: baseline and end of 4 week intervention

Mean Change From Baseline to 12 Weeks in Beck Depression Inventory II (BDI-II) Total Score

A 21-item, patient-completed questionnaire to assess characteristics of depression. Each of the 21 items corresponding to a symptom of depression is summed to give a single score. There is a four-point scale for each item ranging from 0 to 3. Total score of 0-13 is considered minimal range, 14-19 is mild, 20-28 is moderate, and 29-63 is severe. Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Body Weight

Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline through 12 weeks

Mean Change From Baseline to 12 Weeks in Heart Rate

Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline through 12 weeks

Mean Change From Baseline to 12 Weeks in Weekly Mean of Daily 24 Hour Average Pain Score, Duloxetine Compared With Duloxetine+Gabapentin

This is an ordinal scale with scores from 0 (no pain) to 10 (worst possible pain). Data presented represent the weekly mean of the scores of the average pain severity over the last 24 hours. Scores are based on daily assessments recorded by patients in their diaries. Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Weekly Mean of Daily 24 Hour Average Pain Score, Pregabalin Compared With Duloxetine

This is an ordinal scale with scores from 0 (no pain) to 10 (worst possible pain). Data presented represent the weekly mean of the scores of the average pain severity over the last 24 hours. Scores are based on daily assessments recorded by patients in their diaries. Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Weekly Mean of Nighttime Pain Severity

This is an ordinal scale with scores from 0 (no pain) to 10 (worst possible pain). Data presented represent the weekly mean of the scores of the daily nighttime pain severity over the last 24 hours. Scores are based on daily assessments recorded by patients in their diaries. Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Weekly Mean of the Daily Worst Pain Severity Score

This is an ordinal scale with scores from 0 (no pain) to 10 (worst possible pain). Data presented represent the weekly mean of the scores of the daily worst pain severity over the last 24 hours. Scores are based on daily assessments recorded by patients in their diaries. Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Number of Participants With ≥ 30% Reduction in the Weekly Mean 24 Hour Average Pain Score at 12 Weeks

This is a nominal outcome reflecting whether or not a clinically-important efficacy outcome was achieved at endpoint. It is based on a comparison between baseline and endpoint scores on an ordinal scale with scores from 0 (no pain) to 10 (worst possible pain). Used were the weekly mean of the scores of the average pain severity over the last 24 hours. The weekly averages were based on daily assessments recorded by patients in their diaries. (NCT00385671)
Timeframe: baseline, 12 weeks

Number of Participants With a ≥ 2-points Reduction on the Weekly Average of the Daily 24-hour Average Pain Scale at 12 Weeks

This is a nominal outcome reflecting whether or not a clinically-important efficacy outcome was achieved at endpoint. It is based on a comparison between baseline and endpoint scores on an ordinal scale with scores from 0 (no pain) to 10 (worst possible pain). Used were the weekly mean of the scores of the average pain severity over the last 24 hours. The weekly averages were based on daily assessments recorded by patients in their diaries. (NCT00385671)
Timeframe: baseline, 12 weeks

Number of Participants With Treatment-Emergent Elevated Heart Rate

Elevated heart rate: >=100 beats per minute (bpm) + an increase of >=10 bpm if baseline <100 bpm. (NCT00385671)
Timeframe: baseline through 12 weeks

Number of Patients With a Reduction of ≥ 50% in Weekly Mean of 24 Hour Average Pain Score

This is a nominal outcome reflecting whether or not a clinically-important efficacy outcome was achieved at endpoint. It is based on a comparison between baseline and endpoint scores on an ordinal scale with scores from 0 (no pain) to 10 (worst possible pain). Used were the weekly mean of the scores of the average pain severity over the last 24 hours. The weekly averages were based on daily assessments recorded by patients in their diaries. (NCT00385671)
Timeframe: baseline, 12 weeks

Patient's Global Impression of Improvement Scale (PGI - Improvement) at 12 Weeks

A scale that measures the patient's perception of improvement at the time of assessment compared with the start of treatment. The score ranges from 1 (very much better) to 7 (very much worse). (NCT00385671)
Timeframe: 12 weeks

Summary of Number of Participants Who Discontinued

Number of participants who discontinued. The reasons for discontinuation are presented in the participant flow. (NCT00385671)
Timeframe: baseline through 12 weeks

Time to First ≥ 2 Points Reduction in Weekly Mean 24 Hour Average Pain Score

This is the number of days required to first achieve a nominal outcome reflecting whether or not a clinically-important efficacy outcome was achieved. It is based on a comparison between baseline and post-baseline scores on an ordinal scale with scores from 0 (no pain) to 10 (worst possible pain). Used were the weekly mean of the scores of the average pain severity over the last 24 hours. The weekly averages were based on daily assessments recorded by patients in their diaries. (NCT00385671)
Timeframe: baseline through 12 weeks

Time to First ≥ 30% Reduction in Weekly Mean 24 Hour Average Pain Score

This is the number of days required to first achieve a nominal outcome reflecting whether or not a clinically-important efficacy outcome was achieved. It is based on a comparison between baseline and post-baseline scores on an ordinal scale with scores from 0 (no pain) to 10 (worst possible pain). Used were the weekly mean of the scores of the average pain severity over the last 24 hours. The weekly averages were based on daily assessments recorded by patients in their diaries. (NCT00385671)
Timeframe: baseline through 12 weeks

Categorial Change From Baseline to 12 Weeks in Portland Neurotoxicity Scale - Total Score and Subscale Scores

The Portland Neurotoxicity Scale is a 15-item, patient-completed questionnaire designed to assess the degree of impact of anti-epileptic drug therapy on a number of cognitive and somatomotor parameters. Categories: better=negative change in score; same=no change in score; worse=positive change in score. (NCT00385671)
Timeframe: baseline, 12 weeks

Categorical Change From Baseline to 12 Weeks in Number of Patients Using Health Care as Measured by the Resource Utilization Scale

The Resource Utilization Scale measures direct and indirect costs (collected only for US sites). Direct costs include inpatient and outpatient costs, while indirect costs include lost days of work and caregiver time spent with patients. Inpatient costs include costs associated with hospitalizations and time spent in emergency rooms and psychiatric rooms. Outpatient costs include costs associated with visits to various health care providers, home health care by health care providers, and partial care. (NCT00385671)
Timeframe: baseline, 12 weeks

Categorical Change From Baseline to 12 Weeks in Sexual Functioning Questionnaire (CSFQ) Total Score and Subscale Scores

14-item subject-rated scale assessing changes in sexual activity and functioning; structured interview/questionnaire, designed to measure medication related changes in sexual functioning. 5 dimensions of sexual behavior: pleasure; desire/frequency; desire/interest; arousal; orgasm. Total score: obtained across all 5 dimensions, ranges from 14 to 70. Subscale scores: desire/frequency=2-10; desire/interest=3-15; pleasure=1-5; arousal=3-15; orgasm=3-15. Higher scores = better sexual functioning. Categories: better=positive change in score; same=no change in score; worse=negative change in score. (NCT00385671)
Timeframe: baseline, 12 weeks

Discontinuations for Abnormal Laboratory Analytes, Vital Signs, Overall and for Each Measure

Presented are numbers of participants who discontinued due to a change from baseline in laboratory analytes or vital signs. (NCT00385671)
Timeframe: baseline through 12 weeks

Mean Change From Baseline to 12 Weeks in Blood Pressure

Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline through 12 weeks

Mean Change From Baseline to 12 Weeks in Brief Pain Inventory (BPI) - Interference With Enjoyment of Life

A self-reported scale that measures the interference of pain in the past 24 hours on enjoyment of life. The Interference scores range from 0 (does not interfere) to 10 (completely interferes). Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Brief Pain Inventory (BPI) - Interference With Mood

A self-reported scale that measures the interference of pain in the past 24 hours on mood. The Interference scores range from 0 (does not interfere) to 10 (completely interferes). Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Brief Pain Inventory (BPI) - Interference With Normal Work

A self-reported scale that measures the interference of pain in the past 24 hours on normal work. The Interference scores range from 0 (does not interfere) to 10 (completely interferes). Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Brief Pain Inventory (BPI) - Interference With Relations With Other People

A self-reported scale that measures the interference of pain in the past 24 hours on relations with other people. The Interference scores range from 0 (does not interfere) to 10 (completely interferes). Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Brief Pain Inventory (BPI) - Interference With Sleep

A self-reported scale that measures the interference of pain in the past 24 hours on sleep. The Interference scores range from 0 (does not interfere) to 10 (completely interferes). Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Brief Pain Inventory (BPI) - Interference With Walking Ability

A self-reported scale that measures the interference of pain in the past 24 hours on walking ability. The Interference scores range from 0 (does not interfere) to 10 (completely interferes). Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Brief Pain Inventory (BPI) - Interference: With General Activity

A self-reported scale that measures the interference of pain in the past 24 hours on general activity. The Interference scores range from 0 (does not interfere) to 10 (completely interferes). Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Brief Pain Inventory (BPI) - Mean Interference Score

The Interference scores range from 0 (does not interfere) to 10 (completely interferes). There are 7 questions assessing the interference of pain in the past 24 hours for general activity, mood, walking ability, normal work, relations with other people, sleep, and enjoyment of life. Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Brief Pain Inventory (BPI) - Severity: 24-hour Average Pain

A self-reported scale that measures the severity of pain based on the average pain over the past 24-hours. The severity scores range from 0 (no pain) to 10 (pain as severe as you can imagine). Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Brief Pain Inventory (BPI) - Severity: Least Pain

A self-reported scale that measures the severity of pain based on the least pain experienced over the past 24-hours. The severity scores range from 0 (no pain) to 10 (pain as severe as you can imagine). Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Brief Pain Inventory (BPI) - Severity: Pain Right Now

A self-reported scale that measures the severity of pain based on the pain right now. The severity scores range from 0 (no pain) to 10 (pain as severe as you can imagine). Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Brief Pain Inventory (BPI) - Severity: Worst Pain

A self-reported scale that measures the severity of pain based on the worst pain experienced over the past 24-hours. The severity scores range from 0 (no pain) to 10 (pain as severe as you can imagine). Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 Weeks

Mean Change From Baseline to 12 Weeks in Clinical Global Impression of Severity Scale (CGI Severity)

Measures severity of illness at the time of assessment compared with start of treatment. Scores range from 1 (normal, not at all ill) to 7 (among the most extremely ill patients). Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Fasting Plasma Glucose

(NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Hemoglobin A1C

(NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Hepatic Enzyme Serum Levels

Aspartate aminotransferase = AST Alanine aminotransferase = ALT Gamma glutamyl transferase = GGT Alkaline phosphatase = AlkPhos (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Leeds Sleep Evaluation Questionnaire (LSEQ) Subscales of Ease of Going to Sleep (GTS), Awakening (AFS), and Behavior Following Wakefulness (BFW), Quality of Sleep (QOS)

The LSEQ assesses the effects of psychoactive compounds on sleep and early morning behavior. Participants mark a series of 100 mm line analogue scales, indicating the direction and magnitude of any changes in behavioral state they experience following administration of the drug. Scores are represented in millimeters, higher scores indicate better sleep and better early morning behavior. Subscale score ranges: GTS=0-300, QOS=0-200, AFS=0-200, BFW=0-300. Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Portland Neurotoxicity Scale - Total Score and Subscale Scores

The Portland Neurotoxicity Scale is a 15-item, patient-completed questionnaire designed to assess the degree of impact of anti-epileptic drug therapy on a number of cognitive and somatomotor parameters. The total score ranges from 15-135 with higher scores indicating more toxicity. The cognitive toxicity score ranges from 10-90 and the somatomotor toxicity score ranges from 5-45, for both higher scores indicate more toxicity. Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Sexual Functioning Questionnaire (CSFQ) Total Score and Subscale Scores

14-item subject-rated scale assessing medication related changes in sexual activity + functioning. Structured interview/questionnaire. It measures five dimensions of sexual behavior: pleasure; desire/frequency; desire/interest; arousal; and orgasm. The total score is obtained across all 5 dimensions, ranging from 14 to 70. Subscale score ranges: desire/frequency=2-10; desire/interest=3-15; pleasure=1-5; arousal=3-15; orgasm=3-15. Higher scores = better sexual functioning. Least-squares means: adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Sheehan Disability Scale (SDS) - Total Score and Scores for Items 1 to 3

The SDS is completed by the patient and is used to assess the effect of the patient's symptoms on their work/social/family life. Total scores range from 0 to 30, higher values indicate greater disruption in the patient's life. Item 1 assesses the effect of the patient's symptoms on their work/school schedule, Item 2 on their social life/leisure activities, and Item 3 on their family life/home responsibilities. Subscales scores range: 0-10, higher values indicate greater disruption in the patient's life. Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Mean Change From Baseline to 12 Weeks in Total Bilirubin

(NCT00385671)
Timeframe: baseline, 12 weeks

Number of Participants With Treatment-Emergent Changes in Body Weight

"Treatment-emergent high body weight: weight at last visit >=107% of baseline weight.~Treatment-emergent low body weight: weight at last visit <=93% of baseline weight." (NCT00385671)
Timeframe: baseline through 12 weeks

Number of Participants With Treatment-emergent Elevated Blood Pressure

"Elevated systolic blood pressure: >=130 millimeter mercury (mm Hg) + an increase of >=10 mm Hg if baseline <130 mm Hg.~Elevated diastolic blood pressure: >=85 mm Hg + an increase of >=10 mm Hg if baseline <85 mm Hg." (NCT00385671)
Timeframe: baseline through 12 weeks

Number of Patients With Treatment-Emergent Elevated Laboratory Analytes

Treatment-emergent: within range at baseline, out of range after baseline. Ranges in Units/Liter (U/L). Aspartate Aminotransferase (AST): female (f): >34, male (m): >36. Alanine Aminotransferase (ALT): f:<69 years (yr) >34, ≥69yr >32; m: <69yr >43, ≥69yr >35. Total Bilirubin (TBili): >21. Gamma Glutamyl Transferase (GGT): f: <59yr >49, ≥59yr >50; m: <59yr >61, ≥59yr >50. Fasting Plasma Glucose (FPG): <59yr >6.4, ≥59yr >6.7. Hemoglobin A1C (HbA1C) >6%. Alkaline Phosphatase (AlkPhos): f: 18-50yr >106, 50-70yr >123, 70-80yr >164, ≥80yr >221; m: 18-50yr >129, 50-70yr >131, 70-80yr >156, ≥80yr >187 (NCT00385671)
Timeframe: baseline through 12 weeks

Path Analysis of Improvement in Pain Through Improvement in Depressive Symptoms

Contribution to reduction in pain directly by treatment and indirectly by treatment through the reduction of depressive symptoms using path analysis. The direct treatment effect estimates the mean drug difference in pain reduction directly through treatment; the indirect treatment effect estimates the contribution that treatment plays to the mean drug difference in pain reduction indirectly through the reduction in mood symptoms; the total effect estimates the drug difference in reducing pain in sum through the specified path of direct and indirect treatment effects. (NCT00385671)
Timeframe: baseline through 12 weeks

Summary of Adverse Events and Serious Adverse Events Leading to Discontinuation

(NCT00385671)
Timeframe: baseline through 12 weeks

Weekly Mean Change From Baseline to 12 Weeks in 24 Hour Average Pain Severity - Only Participants Who Adhered to Key Protocol Requirements (Per-Protocol Population)

Ordinal scale: 0=no pain, 10=worst possible pain. Data=weekly mean of scores of average pain severity over last 24 hours (h). Scores: daily assessments recorded by patients in diaries. Only patients adhering to key protocol criteria included: baseline Weekly Mean 24h Average Pain Score ≥4; 80-120% compliant with study Drug, each visit; baseline Michigan Neuropathy Screening Instrument Physical Assessment Total Score ≥3; gabapentin taper ≤14 days, no HbA1c ≥12% post randomization; no contraindicated medications used. Least-squares means=adjustment due to baseline severity + investigative site. (NCT00385671)
Timeframe: baseline, 12 weeks

Weekly Mean Change in 24 Hour Average Pain Severity by Week by Gabapentin Exposure Subgroup (de Novo Versus Prior Use)

This is an ordinal scale with scores from 0 (no pain) to 10 (worst possible pain). Data presented represent the weekly mean of the scores of the average pain severity over the last 24 hours. Scores are based on daily assessments recorded by patients in their diaries. De novo: use of gabapentin for <56 contiguous days prior to randomization. Prior use: use of gabapentin for >=56 contiguous days prior to randomization. Least-squares means represent adjustment due to baseline severity and investigative site. (NCT00385671)
Timeframe: baseline, 1 week, 2 weeks, 3 weeks, 4 weeks, 5 weeks, 6 weeks, 7 weeks, 8 weeks, 9 weeks, 10 weeks, 11 weeks, 12 weeks

Change From Baseline in Pain Score After Taking a 50-foot Walk at EOMT

Baseline and EOMT scores are the pain scores each participant reported after taking a 50-foot walk at the randomization and Week 13/Withdrawal visits, respectively, using an 11-point PI-NRS (0=no pain, 10=pain as bad as you can imagine). Change from baseline was calculated as the EOMT score minus the baseline score. An ANCOVA model with BMI, baseline pain intensity after 50-foot walk, pain intensity prior to 50-foot walk at the visit being assessed, and grouped center as covariates was used. (NCT00643760)
Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Change From Baseline in the Mean 24-hour Average Pain Intensity (API) Score at End of Maintenance Treatment (EOMT) Using Last Observation Carried Forward (LOCF) Data

Baseline and EOMT values are the calculated means of the daily 24-hour API scores for each participant during the last 7 days prior to randomization (Baseline) and the earliest date of Week 13 visit/Withdrawal visit/last dose of study drug (EOMT). Participants used a hand-held diary to rate their API over the preceding 24 hours, using an 11-point Pain Intensity Numerical Rating Scale (PI-NRS) (0=no pain, 10=pain as bad as you can imagine). LOCF was used if less than 4 days of diary data were provided. Change from baseline was calculated as the EOMT score minus the Baseline score. (NCT00643760)
Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Change From Baseline in the Mean Current (Evening) Pain Intensity Score at EOMT Using LOCF Data

"Current pain is defined as the participant's assessment of pain intensity right now. Participants recorded their current evening pain intensity in the evening before bedtime using an 11-point PI-NRS (0=no pain, 10=pain as bad as you can imagine). Baseline and EOMT are as defined for the primary endpoint. Change from baseline was calculated as the EOMT score minus the baseline score. An ANCOVA model with baseline value, BMI, grouped center as covariates was used." (NCT00643760)
Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Change From Baseline in the Mean Current (Morning) Pain Intensity Score at EOMT Using LOCF Data

"Current pain is defined as the participant's assessment of pain intensity right now. Participants recorded their current morning pain intensity in the morning upon wakening using an 11-point PI-NRS (0=no pain, 10=pain as bad as you can imagine). Baseline and EOMT are as defined for the primary endpoint. Change from baseline was calculated as the EOMT score minus the baseline score. An ANCOVA model with baseline value, BMI, grouped center as covariates was used." (NCT00643760)
Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)