natriuretic-peptide--brain and Obesity--Morbid

Natriuretic peptides are not only involved in cardiovascular adaption to various conditions, but also in metabolic diseases. We performed this study to assess the effect of a very short time of lifestyle inpatient intervention on NTproBNP values in normotensive subjects with severe obesity and normal cardiac function.. We recruited 14 consecutive obese normotensive subjects with normal cardiac function who were aged 30 years and more and were referred to inpatient rehabilitation in an academic clinic over a two months period. They were examined at baseline and after a 3-weeks program including dietary intervention with hypocaloric diet and assisted personalized physical aerobic and anaerobic activities and compared to age, sex and BMI-matched control subjects under usual care.. BMI significantly decreased (40.8 ±1.6 vs 42.3 ± 1.6 kg/m2, p <0.0001). Median reduction in body weight was 4.9 kg (interquartile range 2.4-5.2 kg). After diet and exercise-induced weight loss, plasma NTproBNP levels showed an almost two-fold increase, which was statistically significant (28.2 ± 12.3 vs 17.2 ± 13.2 ng/L, p = 0.01), and particularly relevant in the subgroup with NT-proBNP values below median values compared to those with higher values (p = 0.02). No significant variations were found in control subjects (18.0 ± 13.0 vs 16.5 ± 11.2 ng/L, p = 0.18). The lipid profile was significantly ameliorated, and both HbA1c and insulin levels showed a marginally non-significant decrease after treatment.. An almost two-fold increase in NTproBNP levels was evident after a very short time period of lifestyle intervention in normotensive severe obese patients without cardiac disease. This finding might have clinical relevance, considering the role of NT-proBNP as risk factor of impaired glucose tolerance.

Topics: Adult; Combined Modality Therapy; Diet, Reducing; Exercise Therapy; Female; Humans; Life Style; Male; Middle Aged; Natriuretic Peptide, Brain; Obesity, Morbid; Peptide Fragments; Time Factors; Treatment Outcome; Weight Reduction Programs

Obese patients have lower plasma concentrations of the cardiac natriuretic peptides (NPs) than their age- and sex-matched counterparts. This may reflect lower production and/or increased peptide clearance. It is unclear whether NP bioactivity is affected by obesity.. We studied the effects of obesity on B-type natriuretic peptide (BNP) clearance and bioactivity by comparing results from standardized intravenous infusions of BNP administered 2 weeks before and 6 months after bariatric surgery in 12 consecutive patients with morbid obesity (body mass index, BMI > 35 kg/m2). Anthropometric, clinical, neurohormonal, renal, and echocardiographic variables were obtained pre- and postsurgery. Pre- vs postsurgery calculated intrainfusion peptide clearances were compared.. BMI (44.3 ± 5.0 vs 33.9 ± 5.2 kg/m2, P < 0.001) and waist circumference (130.3 ± 11.9 vs 107.5 ± 14.7 cm, P < 0.001) decreased substantially after bariatric surgery. Calculated plasma clearance of BNP was reduced (approximately 30%) after surgery. Though not controlled for, sodium intake was presumably lower after bariatric surgery. Despite this, preinfusion endogenous plasma NP concentrations did not significantly differ between pre- and postsurgery studies. The ratio of plasma N-terminal (NT)-proBNP to 24 h urine sodium excretion was higher postsurgery (P = 0.046; with similar nonsignificant findings for BNP, atrial NP (ANP) and NT-proANP), indicating increased circulating NPs for a given sodium status. Mean plasma NP concentrations for given calculated end-systolic wall stress and cardiac filling pressures (as assessed by echocardiographic E/e') rose slightly, but not significantly postsurgery. Second messenger, hemodynamic, renal, and neurohormonal responses to BNP were not altered between studies.. Obesity is associated with increased clearance, but preserved bioactivity, of BNP.

Topics: Atrial Natriuretic Factor; Bariatric Surgery; Humans; Natriuretic Peptide, Brain; Natriuretic Peptides; Obesity, Morbid; Peptide Fragments; Sodium

Obesity is associated with a "natriuretic handicap" indicated by reduced N-terminal fragment of proBNP (NT-proBNP) concentration. While gastric bypass surgery improves the natriuretic handicap, it is presently unclear if sleeve gastrectomy exhibits similar effects. We examined NT-proBNP serum concentration in n = 72 obese participants without heart failure before and 6 months after sleeve gastrectomy (n = 28), gastric bypass surgery (n = 19), and 3-month 800 kcal/day very-low calorie diet (n = 25). A significant weight loss was observed in all intervention groups. Within 6 months, NT-proBNP concentration tended to increase by a median of 44.3 pg/mL in the sleeve gastrectomy group (p = 0.07), while it remained unchanged in the other groups (all p ≥ 0.50). To gain insights into potential effectors, we additionally analyzed NT-proBNP serum concentration in n = 387 individuals with different metabolic phenotypes. Here, higher NT-proBNP levels were associated with lower nutritional fat and protein but not with carbohydrate intake. Of interest, NT-proBNP serum concentrations were inversely correlated with fasting glucose concentration in euglycemic individuals but not in individuals with prediabetes or type 2 diabetes. In conclusion, sleeve gastrectomy tended to increase NT-proBNP levels in obese individuals and might improve the obesity-associated "natriuretic handicap". Thereby, nutritional fat and protein intake and the individual glucose homeostasis might be metabolic determinants of NT-proBNP serum concentration.

Topics: Adult; Aged; Biomarkers; Body Mass Index; Cohort Studies; Female; Gastrectomy; Gastric Bypass; Heart Failure; Humans; Male; Middle Aged; Natriuretic Peptide, Brain; Obesity, Morbid; Peptide Fragments; Weight Loss; Young Adult

Gut-kidney signaling is implicated in sodium homeostasis and thus blood pressure regulation. Roux-en-Y gastric bypass (RYGB) surgery for morbid obesity confers a pronounced and long-lasting blood pressure lowering effect in addition to significant weight loss.. We set out to establish whether RYGB is associated with an intrinsic change in urinary sodium excretion that may contribute to the reported blood pressure lowering effects of the procedure.. University hospital METHODS: Five female patients (age range: 28-50 yr) without metabolic or hypertensive co-morbidities were included in a study involving four 24-hour residential visits: once before surgery and 10 days, 3 months, and 20 months after surgery. Creatinine and sodium were measured in fasting plasma samples and 24-hour urine samples and creatinine clearance, estimated glomerular filtration rate, and indices of urinary sodium excretion were calculated. Fasting and 60-minute postprandial blood samples from each study day were assayed for pro-B-type natriuretic peptide (NT-proBNP).. Increases in weight-normalized urinary sodium excretion of up to 2.3-fold in magnitude occurred at 20 months after surgery. Median fractional excretion of sodium at 20 months was double that seen before surgery. Fasting NT-proBNP levels were stable or increased (1.5- to 5-fold). Moreover, a small postprandial increase in NT-proBNP was observed after surgery.. Renal fractional excretion of sodium is increased after RYGB. A shift toward increased postoperative basal and meal associated levels of NT-proBNP coincides with increased urinary sodium excretion. The data support a working hypothesis that an enhanced natriuretic gut-kidney signal after RYGB may be of mechanistic importance in the blood pressure lowering effects of this procedure.

Topics: Adult; Creatinine; Female; Gastric Bypass; Humans; Iron; Middle Aged; Natriuretic Peptide, Brain; Obesity, Morbid; Peptide Fragments; Postoperative Care; Prospective Studies; Renal Elimination; Sodium; Urination; Weight Loss

The B-type natriuretic peptide (BNP) hormone plays a crucial role in the regulation of cardiovascular and energy homeostasis. Obesity is associated with low circulating levels of BNP, a condition known as "natriuretic handicap." Recent evidences suggest an altered expression of BNP receptors-both the signaling natriuretic peptide receptors (NPR)-A and the clearance NPR-C receptor-in adipose tissue (AT) as one of the putative causes of natriuretic handicap. The current study aims at clarifying the molecular mechanisms behind the natriuretic handicap, focusing on NPR modulation in the AT of obese and control subjects. The study enrolled 34 obese and 20 control subjects undergoing bariatric or abdominal surgery, respectively. The main clinical and biochemical parameters, including circulating BNP, were assessed. In visceral (VAT) and subcutaneous AT (SAT) samples, collected during surgery, the adipocytes and stromal vascular fraction (SVF) expression of NPR-A and NPR-C and the SVF secretion of interleukin 6 (IL-6) were determined. Both VAT and SAT from obese patients expressed a lower NPR-A/NPR-C ratio in adipocytes and the SVF secreted a higher level of IL-6, compared with the controls. Moreover, NPR-A/NPR-C ratio expressed by VAT and SAT adipocytes negatively correlated with body mass index, insulin, the Homeostasis Model Assessment of Insulin resistance, and IL-6 secreted by SVF, and the expression of the clearance receptor NPR-C, in both the VAT and SAT adipocytes, showed a negative correlation with circulating BNP. Overall, insulin resistance/hyperinsulinemia and AT inflammation (ie, high level of IL-6) are the major determinants of the lower NPR-A/NPR-C ratio in adipocytes, thus contributing to the natriuretic handicap in obese subjects.

Topics: Adipocytes; Adipose Tissue; Adult; Case-Control Studies; Female; Gene Expression Regulation; Humans; Interleukin-6; Male; Middle Aged; Natriuretic Peptide, Brain; Obesity, Morbid; Receptors, Atrial Natriuretic Factor

morbid obesity is associated with cardiovascular comorbidity. A noteworthy feature of this relationship could regard low levels of brain natriuretic peptide (BNP). The study investigates the relationship between BNP and obesity-related markers in a morbid obese population, along with echocardiographic and vascular parameters.. in 154 morbid obese patients we evaluated anthropometric parameters, glycometabolic/lipid profile, bioimpedentiometry, echocardiography, visceral fat area and flow-mediated dilation (FMD) by ultrasonography.. we divided population in two groups on the basis of median BMI levels; patients with higher BMI had significantly lower BNP (p = .008), FMD (p = .014) and HDL-C (p = .001) and showed a more impaired heart function. A similar trend emerged subdividing patients on the basis of median visceral fat area. BNP showed a significant inverse correlation with BMI (p < .001), left ventricular mass (p = .026) and inter-ventricular septum thickness (p = .007) and a significant positive correlation with FMD (p = .008), HDL-C (p = .022), and ejection fraction (p = .013). BMI and triglycerides were independent predictors of BNP levels.. patients with higher BMI show lower BNP levels associated with greater total body fat amount. The correlation of BNP with endothelium-dependent vasodilation and cardiac impairment could represent another link between obesity and cardiovascular damage.

Topics: Adiposity; Adult; Bariatric Surgery; Biomarkers; Body Mass Index; Cross-Sectional Studies; Down-Regulation; Female; Hospitals, Urban; Humans; Insulin Resistance; Intra-Abdominal Fat; Italy; Male; Middle Aged; Natriuretic Peptide, Brain; Obesity, Morbid; Outpatient Clinics, Hospital; Ultrasonography; Waist Circumference

Levels of B-type natriuretic peptide (BNP), a prognostic marker in patients with heart failure (HF), are lower among HF patients with obesity or preserved Left Ventricular Ejection Fraction (LVEF). We examined the distribution and prognostic value of BNP across BMI categories in acute decompensated heart failure (ADHF) patients with preserved vs. reduced LVEF.. We analyzed data from the Atherosclerosis Risk in Communities (ARIC) HF surveillance study which sampled and adjudicated ADHF hospitalizations in patients aged ≥55years from 4 US communities (2005-2009). We examined 5 BMI categories: underweight (<18.5kg/m. The cohort included 9820 weighted ADHF hospitalizations (58% HFrEF; 42% HFpEF). BNP levels were lower in HFpEF compared to HFrEF (p<0.001) and decreased as BMI increased within the LVEF groups (p<0.001). After adjustment for covariates, log10 BNP independently predicted 1-year mortality (adjusted OR 1.62 (95% CI 1.17-2.24)) with no significant interaction by BMI or LVEF groups.. BNP levels correlated inversely with BMI, and were higher in HFrEF compared to HFpEF. Obese patients with HFpEF and ADHF had a significant proportion with BNP levels below clinically accepted thresholds. Nevertheless, BNP was a predictor of mortality in ADHF across groups of BMI in HFpEF and HFrEF.

Topics: Acute Disease; Aged; Atherosclerosis; Biomarkers; Body Mass Index; Female; Heart Failure; Humans; Incidence; Male; Middle Aged; Natriuretic Peptide, Brain; Obesity, Morbid; Prognosis; Risk Assessment; Risk Factors; Stroke Volume; Survival Rate; United States; Ventricular Function, Left

In epidemiologic studies, obesity has been associated with reduced natriuretic peptide (NP) concentrations. Reduced NP production could impair the ability of obese individuals to respond to salt loads, increasing the risk of hypertension and other disorders. We hypothesized that weight loss enhances NP production before and after salt loading.. We enrolled 15 obese individuals (mean BMI 45±5.4 kg/m(2)) undergoing gastric bypass surgery. Before and 6 months after surgery, subjects were admitted to the clinical research center and administered a large-volume intravenous saline challenge. Echocardiography and serial blood sampling were performed. From the pre-operative visit to 6 months after surgery, subjects had a mean BMI decrease of 27%. At the 6-month visit, N-terminal pro-atrial NP (Nt-proANP) levels were 40% higher before, during, and after the saline infusion, compared with levels measured at the same time points during the pre-operative visit (P<0.001). The rise in Nt-pro-ANP induced by the saline infusion (≈50%) was similar both before and after surgery (saline, P<0.001; interaction, P=0.2). Similar results were obtained for BNP and Nt-proBNP; resting concentrations increased by 50% and 31%, respectively, after gastric bypass surgery. The increase in NP concentrations after surgery was accompanied by significant decreases in mean arterial pressure (P=0.004) and heart rate (P<0.001), and an increase in mitral annular diastolic velocity (P=0.02).. In obese individuals, weight loss is associated with a substantial increase in the "setpoint" of circulating NP concentrations. Higher NP concentrations could contribute to an enhanced ability to handle salt loads after weight loss.

Topics: Adult; Body Mass Index; Cardiovascular Diseases; Cohort Studies; Echocardiography, Doppler; Enzyme-Linked Immunosorbent Assay; Female; Gastric Bypass; Humans; Hypertension; Infusions, Intravenous; Male; Middle Aged; Monitoring, Physiologic; Natriuretic Peptide, Brain; Obesity, Morbid; Peptide Fragments; Postoperative Care; Preoperative Care; Prognosis; Sodium Chloride; Weight Loss

Topics: Anastomosis, Roux-en-Y; Body Mass Index; Female; Gastric Bypass; Humans; Male; Natriuretic Peptide, Brain; Obesity, Morbid

Obesity is often associated with the development of cardiac hypertrophy but the hypertrophy-related pathways in obesity remain unknown. The purpose of this study was to evaluate cardiac hypertrophy-related markers, atrial natriuretic peptide (ANP), B-type natriuretic peptide (BNP), tumor necrosis factor-alpha (TNFα) and hypertrophy-related pathways, interleukin (IL)-6-STAT3, IL-6-MEK5-ERK5 and calcineurin-nuclear factor of activated T-cells (NFAT)3 in the excised hearts from obese rats. Twelve obese Zucker rats were studied at 5-6 months of age and twelve age-matched lean Zucker rats served as the control group. The cardiac characteristics, myocardial architecture, ANP, BNP, TNFα levels, IL-6, STAT3, p-STAT3, MEK5, ERK-5, p-ERK-5, calcineurin and NFAT3 in the left ventricle from the rats were measured by heart weight index, echocardiography, vertical cross section, histological analysis, reverse transcription polymerase chain reaction and western blotting. Compared with the lean control, the whole heart weight, the left ventricule weight, the ratio of the whole heart weight to tibia length, echocardiographic interventricular septum, left ventricular posterior wall thickness, myocardial morphological changes and systolic blood pressure were found to increase in the obese rats. The protein levels of ANP, BNP, TNFα, IL-6, STAT3, p-STAT3, MEK-5, ERK-5, p-ERK 5, calcineurin and NFAT3 were also significantly increased in the hearts of the obese rats. The results showed that the hypertrophy-related markers, ANP, BNP and TNFα, the hypertrophy-related pathways IL-6-STAT3 and IL-6-MEK5-ERK5, and the calcineurin-NFAT3 hypertrophy-related pathways were more active in obese Zucker rats, which may provide possible hypertrophic mechanisms for developing cardiac hypertrophy and pathological changes in obesity.

Topics: Animals; Atrial Natriuretic Factor; Cardiomegaly; Disease Models, Animal; Interleukin-6; Male; MAP Kinase Kinase 5; MAP Kinase Signaling System; Mitogen-Activated Protein Kinase 7; Natriuretic Peptide, Brain; Obesity, Morbid; Rats, Zucker; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; STAT3 Transcription Factor; Tumor Necrosis Factor-alpha

Brain natriuretic peptide (BNP) is produced in the heart in response to stretching of the myocardium. BNP levels are negatively correlated to obesity, and in obese subjects, a reduced BNP responsiveness has been described. Diet-induced weight loss has been found to lower or to have no effect on BNP levels, whereas gastric banding and gastric bypass have reported divergent results. We studied obese patients undergoing gastric bypass (GBP) surgery during follow-up of 1 year.. Twenty patients, 18 women, mean 41 (SD 9.5) years old, with a mean preoperative BMI of 44.6 (SD 5.5) kg/m(2) were examined. N-terminal pro-brain natriuretic peptide (NT-ProBNP), glucose and insulin were measured preoperatively, at day 6 and months 1, 6 and 12. In 14 of the patients, samples were also taken at days 1, 2 and 4.. The NT-ProBNP levels showed a marked increase during the postoperative week (from 54 pg/mL preop to 359 pg/mL on day 2 and fell to 155 on day 6). At 1 year, NT-ProBNP was 122 pg/mL (125 % increase, p = 0.01). Glucose, insulin and HOMA indices decreased shortly after surgery without correlation to NT-ProBNP change. Mean BMI was reduced from 44.6 to 30.5 kg/m(2) at 1 year and was not related to NT-ProBNP change.. The data indicate that GBP surgery rapidly alters the tone of BNP release, by a mechanism not related to weight loss or to changes in glucometabolic parameters. The GBP-induced conversion of obese subjects, from low to high NT-ProBNP responders, is likely to influence the evaluation of cardiac function in GBP operated individuals.

Topics: Adult; Blood Glucose; Body Mass Index; Fasting; Female; Follow-Up Studies; Gastric Bypass; Gastroplasty; Heart Failure; Homeostasis; Humans; Insulin; Male; Natriuretic Peptide, Brain; Obesity, Morbid; Peptide Fragments; Postoperative Period; Predictive Value of Tests; Prospective Studies; Risk Factors; Sweden; Treatment Outcome; Weight Loss

This study aimed to examine the incremental value of growth-differentiation factor-15 (GDF-15) to N-terminal pro brain natriuretic hormone (NT-proBNP) levels for the diagnosis of left ventricular diastolic dysfunction (LVDD) and possible heart failure (HF) in morbidly obese patients. Method and results We analysed data from 207 obese subjects [body mass index (BMI) 41 ± 8 kg/m(2)] with normal ejection fraction, LVDD, and symptoms and/or signs of HF (referred to as 'LVDD with possible HF', n = 88) and with normal left ventricular function (n = 119) before participating in a medical weight loss programme, in addition to the study of healthy lean subjects (n = 51). Median NT-proBNP (interquartile range) for obese subjects with 'LVDD and possibe HF' and with normal LV function was 52 (29-96) and 42 (25-66) pg/mL, respectively (P = 0.12). There was no correlation of NT-proBNP with parameters of left ventricular filling pressure, i.e. E/E' (r(2) = 0.002, P = 0.63) or E' velocity (r(2) = 0.02, P = 0.24). In contrast, GDF-15 was 665 (496-926) with 'LVDD and possible HF' and 451 (392- 679) pg/mL without (P < 0.0001). GDF-15 was significantly correlated to E/E', E' velocity, E/A ratio, isovolumetric relaxation time, duration of reversed pulmonary vein atrial systolic flow, and left atrial size. The area under the receiver operating characteristic curve that defines LVDD with possible HF was 0.56 for NT-proBNP and 0.74 for GDF-15 (P < 0.0001). The addition of GDF-15 to a multivariate predicition model increased the net reclassification improvement (NRI) by 9% (P= 0.022).. In morbidly obese individuals, GDF-15 levels seem to better correlate with diastolic dysfunction than NT-proBNP levels. GDF-15 significantly improves reclassification for the diagnosis of 'LVDD with possible HF' and, thus, adds incremental value to NT-proBNP.

Topics: Adolescent; Adult; Analysis of Variance; Biomarkers; Female; Growth Differentiation Factor 15; Health Status Indicators; Heart Failure, Diastolic; Humans; Male; Middle Aged; Natriuretic Peptide, Brain; Obesity, Morbid; Peptide Fragments; Predictive Value of Tests; Prognosis; Statistics as Topic; Ultrasonography; Ventricular Dysfunction, Left; Young Adult

Coronary artery disease is the primary cause of death in the United States, with obesity as a leading preventable risk factor. Previous studies have established the beneficial effect of Roux-en-Y gastric bypass on both weight and cardiac risk factors. Further assessment of cardiac function may be accomplished using B-type natriuretic peptide (BNP), which has demonstrated clinical utility in diagnosing congestive heart failure. This study aimed to assess changes in BNP after intentional weight loss through gastric bypass surgery.. Plasma volume, weight, and BNP were measured preoperatively and at 3, 6, and 12 months postoperatively for 101 consecutive patients undergoing laparoscopic gastric bypass surgery by a single surgeon in an academic medical setting. Outcomes were compared by matched t-test. Multivariable linear regression and Pearson's correlation were used to examine predictors of pro-B-type natriuretic peptide (NT-proBNP) concentration.. The concentration of BNP increased significantly from a mean preoperative level of 50.5 ng/l to postoperative levels of 73.9 ng/l at 3 months (P=0.013), 74.3 ng/l at 6 months (P<0.001), and 156.3 ng/l at 12 months (P<0.001). In addition, excess weight loss was the only statistically significant predictor of increased BNP concentration (odds ratio, 1.483; P<0.05).. Gastric bypass leads to significant excess weight loss and surprisingly increased BNP concentrations. Correlation of BNP increase with weight loss suggests an additional novel mechanism for surgically induced weight loss.

Topics: Anastomosis, Roux-en-Y; Biomarkers; Cardiovascular Diseases; Female; Gastric Bypass; Humans; Linear Models; Lipids; Logistic Models; Male; Middle Aged; Natriuretic Peptide, Brain; Obesity, Morbid; Plasma Volume; Risk Factors; Weight Loss

Brain natriuretic peptide (BNP) has potent lipolytic action and, probably, a role in the biological mechanisms of obesity. Clinically, high levels are found in subjects with heart failure (HF). Low levels and inverse relation to BMI lead to questioning of its clinical utility in obese subjects, but heterogeneous results are found in severe obesity.. In order to describe BNP behavior and its metabolic and cardiovascular determinants in class III obesity, we performed BNP measurement as well as clinical and echocardiographic evaluation of 89 subjects from two public hospitals in Brazil. Multivariate logistic ordinal regression with BNP tertiles as the dependent variable was performed.. Mean (± SD) age and BMI (± SD) was 44 ± 11.5 years and 53.2 ± 7.9 kg/m(2), respectively. 72 (81%) participants were women, and 18 (20%) had HF. Median BNP was 9.5 pg/ml(Q1 4.9; Q3 21.2 pg/ml). 30% of BNP values were below the detection limit of the method. In multivariate analysis, left atrial volume (LAV) was the only determinant of BNP levels (p 0.002) with odds-ratio of 1.1 (95% CI 1.03-1.16).. BNP levels are low in severe obesity, even in subjects with HF. LAV, which marks diastolic dysfunction, determines BNP levels, but not BMI and metabolic abnormalities.

Topics: Adult; Biomarkers; Body Mass Index; Diastole; Echocardiography; Female; Heart Atria; Heart Failure; Humans; Logistic Models; Male; Middle Aged; Multivariate Analysis; Natriuretic Peptide, Brain; Obesity, Morbid; Odds Ratio; Prevalence; Stroke Volume

Sleep-disordered breathing (SDB) is often encountered in morbid obesity (MO) in conjunction with insulin resistance (IR) and several cardio-vascular risk factors. Aminoterminal pro-brain natriuretic peptide (NT-proBNP) is a promising marker for left ventricular dysfunction (LVD) in MO. The aim of this study was to look for possible correlations between SDB, IR, heart structure and function indexes and NT-proBNP levels in MO female subjects.. Cross-sectional study involving 110 MO (44.5+/-0.7 kg m(-2)) apparently healthy, young (37.8+/-1.0 y.o.) female patients. NT-proBNP was measured using an ELISA kit (Roche). Echo-cardiograms were performed to quantify left ventricular ejection fraction values (LVEF), cardiac output (CO), left ventricular mass (LVM), left atria size (LA) and left ventricular filling pressures (the E/Em ratio). The Berlin Questionnaire (BQ) was used to assess the risk of SDB. IR and sensitivity were assessed using the HOMA index and adiponectin measurements, respectively.. All patients had a normal LVEF (>50%). Hypertension and Type 2 diabetes mellitus prevalences were 34.5 and 4.5% (respectively). Log-transformed NT-proBNP levels correlated with BQ categories (P<0.0005), creatinine (P<0.001), age (P<0.05), LVM (P<0.001), CO (P<0.001), LA (P<0.0005) and E/Em (P<0.01). NT-proBNP levels, LVD and LVM increased significantly along with BQ scores (P<0.0001). Stepwise multiple regression analysis identified BQ and log-transformed HOMA as independent variables predicting as much as 48.0% of log-transformed NT-proBNP's variability (dependent variable).. NT-proBNP levels are independently predicted by SDB and IR in asymptomatic MO women. Additionally, SDB worsens along with LVH and diastolic dysfunction. Larger prospective studies are warranted.

Topics: Adult; Biomarkers; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Echocardiography; Female; Humans; Hypertension; Hypertrophy, Left Ventricular; Insulin Resistance; Linear Models; Natriuretic Peptide, Brain; Obesity, Morbid; Peptide Fragments; Predictive Value of Tests; Prevalence; Risk Factors; Sleep Apnea Syndromes

Sleep-disordered breathing (SDB) is often encountered in morbid obesity (MO) in conjunction with insulin resistance (IR). Aminoterminal pro-brain natriuretic peptide (NT-proBNP) is a promising marker for left ventricular dysfunction (LVD) in MO. We sought to explore the factors that may influence the relationships of SDB and IR with NT-proBNP in MO women. We performed a cross-sectional pilot study involving 110 asymptomatic MO (44.5+/-0.7 kg/m2) young women. SDB risk was assessed using a modified version of the Berlin Questionnaire (BQ). IR was assessed using the homeostasis model assessment (HOMA) index and adiponectin levels. LVD was assessed using NT-proBNP and echocardiograms. In this study, NT-proBNP levels and LVD increased significantly along the BQ strata. Multiple regression analysis identified BQ and log-transformed HOMA as the independent variables predicting as much as 48.0% of the variability of logNT-proBNP. In conclusion, NT-pro-BNP levels are independently predicted by SDB and IR in asymptomatic MO women. Larger prospective studies are warranted.

Topics: Adiponectin; Adult; Biomarkers; Cross-Sectional Studies; Echocardiography; Female; Humans; Insulin Resistance; Middle Aged; Natriuretic Peptide, Brain; Obesity, Morbid; Peptide Fragments; Sleep Apnea Syndromes; Surveys and Questionnaires; Ventricular Dysfunction, Left

Elevated body mass index (BMI) has been reported as a risk factor for heart failure. Prevention of heart failure through identification and management of risk factors and preclinical phases of the disease is a priority. Levels of natriuretic peptides as well as activity of their receptors have been found altered in obese persons with some conflicting results. We investigated cardiac involvement in severely obese patients by determining N-terminal-pro-brain natriuretic peptide (NT-proBNP) and brain natriuretic peptide (BNP) and attempting to correlate the levels of these peptides in serum and plasma, respectively, with BMI, duration of obesity, waist circumference, and echocardiographic parameters. Thirty-three patients with severe obesity (mean BMI: 46.39 kg/m(2), mean age: 39 years) were studied. The control group contained 30 healthy age-matched individuals (BMI: <25 kg/m(2), mean age: 43 years). The t-test and Spearman correlation were used for statistical analysis. Log-NT-proBNP was significantly higher (P = 0.003) in obese patients (mean 1.67, 95% CI: 1.50-1.83 log pg/mL) compared to controls (mean: 1.32, 95% CI: 1.17-1.47 log pg/mL). The Log-NT-proBNP concentration correlated with duration of obesity (r = 0.339, P < 0.004). No difference was detected in the Log-BNP concentration (P = 0.63) of obese patients (mean: 0.73, 95% CI: 0.46-1.00 log pg/mL) compared to controls (mean: 0.66, 95% CI: 0.51-0.81 log pg/mL). NT-proBNP, but not BNP, is increased in severely obese patients and its concentration in serum is correlated with duration of obesity. NT-proBNP may be useful as an early diagnostic tool for the detection of cardiac burden due to severe obesity.

Topics: Adult; Biomarkers; Body Mass Index; Case-Control Studies; Echocardiography; Female; Heart Diseases; Humans; Luminescent Measurements; Male; Natriuretic Peptide, Brain; Obesity, Morbid; Peptide Fragments; Risk Factors; Severity of Illness Index; Statistics, Nonparametric; Time Factors; Waist-Hip Ratio

Aminoterminal pro-brain natriuretic peptide (NT-proBNP), like brain natriuretic peptide, might have diagnostic utility in detecting left ventricular hypertrophy and/or left ventricular dysfunction. The aim of the study was to investigate the relationship between morbid obesity and NT-proBNP and the effect of weight reduction on this parameter.. A total of 34 morbidly obese patients underwent laparoscopic adjustable gastric banding (LAGB). NT-proBNP levels were measured before and 12 months after the surgery.. Metabolic features and systolic and diastolic blood pressure were significantly decreased (p < 0.00001 for both) after a cumulative weight loss of 19.55 kg 1 year after LAGB. NT-proBNP concentration was significantly higher in morbidly obese patients before LAGB than in normal-weight control subjects (341.15 +/- 127.78 fmol/mL vs. 161.68 +/- 75.78 fmol/mL; p < 0.00001). After bariatric surgery, NT-proBNP concentration decreased significantly from 341.15 +/- 127.78 fmol/mL to 204.87 +/- 59.84 fmol/mL (p < 0.00001) and remained statistically significantly elevated (204.88 +/- 59.84 fmol/mL vs. 161.68 +/- 75.78 fmol/mL; p = 0.04) compared with normal-weight subjects.. This investigation demonstrates higher levels of NT-proBNP in morbidly obese subjects and a significant decrease during weight loss after laparoscopic adjustable gastric banding. In obesity, NT-proBNP might be useful as a routine screening method for identifying left ventricular hypertrophy and/or left ventricular dysfunction.

Topics: Adult; Blood Pressure; Body Mass Index; Female; Gastroplasty; Humans; Male; Middle Aged; Natriuretic Peptide, Brain; Nerve Tissue Proteins; Obesity, Morbid; Peptide Fragments; Weight Loss