vitamin-k-semiquinone-radical and Obesity--Morbid

Obesity is associated with increased risks of atrial fibrillation (AF) and venous thromboembolism (VTE) for which anticoagulation is commonly used. However, data on the efficacy and safety of oral anticoagulants in patients with morbid obesity are limited.. We conducted a systematic review and meta-analysis to evaluate the efficacy and safety of direct oral anticoagulants (DOACs) or vitamin K antagonists (VKAs) for AF or VTE in patients with morbid obesity.. Patients with morbid obesity on DOACs had similar risks of stroke/systemic embolism, lower rates of recurrent VTE, and major bleeding events compared to those on VKAs. However, the certainty of evidence was low given that studies were mostly observational with high risk of confounding.

Topics: Administration, Oral; Anticoagulants; Atrial Fibrillation; Hemorrhage; Humans; Obesity, Morbid; Stroke; Venous Thromboembolism; Vitamin K

Current guidelines give class I recommendations for uninterrupted use of dabigatran rivaroxaban as an alternative to vitamin K antagonist (VKA) in patients of atrial fibrillation (AF) who are undergoing catheter ablation. The recent randomized controlled trials have shown similar efficacy of novel oral anticoagulants when compared to VKA in these patients. We sought to perform a meta-analysis with a focus on subgroup analysis of novel oral anticoagulants.. We searched PubMed, Clinical trials registry and the Cochrane Center Register of Controlled Trials were searched through August 2020. Six RCTs studies (n = 2260) comparing the use of NOACs versus VKA in patients with AF undergoing catheter ablation were included. The odds ratio (OR) with 95% confidence interval was computed and P < 0.05 was considered as a level of significance. Major adverse cardiac events (MACE) were considered as a primary endpoint.. Our results showed a significant difference in MACE between NOACs and VKA [OR 0.57 (0.37-0.88); P = 0.01] and in major bleeding events [OR 0.55 (0.35-0.86); P = 0.009], which is mainly derived from the use of dabigatran. No significant difference in MACE or major bleeding events was found on the subgroup analysis of rivaroxaban and apixaban over VKA therapy.. Uninterrupted use of NOACs is safe and effective alternative for the prevention of cerebral thromboembolism and reducing the risk of major bleeding in patients undergoing catheter ablation of AF. However, the individual subgroup analysis showed that only dabigatran is superior to VKA in terms of reducing MACE through a reduction in major bleeding. The rivaroxaban, apixaban and edoxaban are non-inferior to VKA therapy based on these results. Further studies are needed to generalize these recommendations in morbidly obese patients.

Topics: Administration, Oral; Anticoagulants; Atrial Fibrillation; Catheter Ablation; Humans; Obesity, Morbid; Rivaroxaban; Stroke; Treatment Outcome; Vitamin K

Vitamin K, a fat-soluble vitamin, is involved in blood coagulation, bone mineralization, inhibition of vascular calcification, and regulation of numerous enzyme systems. Patients who undergo bariatric surgery (BS), especially procedures that involve a malabsorptive component, are prone to develop vitamin K deficiency (VKD). The causes of VKD include decreased absorptive surface areas, steatorrhea, bacterial overgrowth, marked reduction of carriers of vitamin K, decrease in vitamin K intake, and modifications of gut microbiota. Data on vitamin K status among BS patients are scarce and the strength of evidence supporting vitamin K supplementation is weak. Thus, this systematic review summarized the scientific literature on vitamin K and examined the status among patients before and after BS, as well as among pregnant women with a history of BS. A MEDLINE/Pubmed and Embase electronic search was performed. After a thorough screening of 204 titles, 19 articles were selected by 2 independent reviewers. Five studies on BS candidates (n = 750), 12 studies after BS (n = 1442), and 4 studies on pregnant woman after BS (n = 83, of them n = 7 from case reports) were included. Results of the current review suggest that patients who undergo major malabsorptive surgeries are at a higher risk of developing VKD and should be better monitored. At this point, it is still unclear whether supplementation of vitamin K is required, and what oral dose or vitamer type should be used to normalize serum levels after different types of bariatric procedures. It should be noted that the current protocols for VKD treatment are still experiential in these patients. It is also unknown at what intervals screening tests for vitamin K should be performed and what assay is most appropriate for screening purposes. Future studies are needed to answer these unresolved issues.

Topics: Adult; Aged; Bariatric Surgery; Female; Humans; Malabsorption Syndromes; Male; Middle Aged; Obesity, Morbid; Postoperative Complications; Pregnancy; Vitamin K; Vitamin K Deficiency; Young Adult

Numerous factors are well documented to affect the response to vitamin K antagonists (VKA), including dietary vitamin K, other drugs, age, pharmacogenetics, and disease states. Body weight is perhaps not as well known as a variable affecting VKA dose. Our aim was to review the literature regarding body weight and VKA dose requirements.. We reviewed the English-language literature via PubMed and Scopus using the search terms VKA, warfarin, acenocoumarol, phenprocoumon, fluindione, AND body weight.. Among 32 studies conducted since the widespread use of the international normalized ratio, 29 found a correlation with body weight or body surface area and VKA dose requirement. Warfarin was evaluated in 27 studies and acenocoumarol, phenprocoumon, or fluindione were assessed in 5 investigations.. Because of varying study methodologies, further study is warranted. Based on current evidence, clinicians should include body weight, along with other established variables when dosing VKA. Most important, obese and morbidly obese patients may require a 30% to 50% increase with the initial dosing of VKA.

Topics: Acenocoumarol; Anticoagulants; Body Weight; Comorbidity; Drug Dosage Calculations; Humans; Obesity; Obesity, Morbid; Phenindione; Phenprocoumon; Vitamin K; Warfarin

Micronutrient deficiencies are common complications after bariatric surgery as alterations to the gastrointestinal tract change absorption. Patients are recommended to take supplements including multivitamins, B complex, calcium, vitamin D, and iron after bariatric surgery, and can take these as specifically formulated vitamins for post-bariatric patients or separate vitamin supplements. We investigated the compliance, efficacy, and cost of specifically formulated vitamins for post-bariatric patients in comparison to separate vitamin supplements.. We surveyed 126 post-bariatric adult patients between February 1, 2022, and August 31, 2022, who had undergone bariatric surgery between 2014 and 2021 to assess the type of supplements taken, compliance, and cost. Demographics, type of bariatric surgery, and serum micronutrient levels were evaluated for all patients.. There were 51 patients taking formulated vitamins and 75 patients taking separate vitamins. The formulated vitamin group demonstrated greater adherence to optimal vitamin dosage (formulated vitamin group, 76.5% vs. separate supplement group, 30.7%; p < 0.001) and higher compliance (formulated vitamin group, 90.2% vs. separate supplement group, 66.7%; p = 0.002). The costs associated with both groups were comparable. No significant difference was observed in the incidence of micronutrient deficiency between the groups.. Our study shows that formulated vitamins do not offer significant difference in micronutrient levels or cost compared to separate standard vitamin supplements. However, formulated bariatric vitamins have improved compliance compared to separate vitamin supplements.

Topics: Adult; Bariatric Surgery; Humans; Obesity, Morbid; Vitamin A; Vitamin K; Vitamins

Micronutrient deficiencies occur in morbidly obese patients. The aim of this study was to assess vitamin deficiencies prior to bariatric surgery including vitamin K about which there is little data in this population.. A prospective assessment of 118 consecutive patients was performed. Clinical allied with haematological and biochemical variables were measured. Micronutrients measured included vitamins K1 , PIVKA-II (protein-induced in vitamin K absence factor II), vitamin D, vitamin B12 (holotranscobalamin), iron, transferrin and folate.. Patients were aged 49 ± 11 [mean (SD, standard deviation)] years, body mass index (BMI) 50 ± 8 kg/m(2), 66% female and 78% Caucasian. Hypertension was present in 47% and type 2 diabetes in 32%. Vitamin D supplements had been prescribed in 8%. Micronutrient insufficiencies were found for vitamin K (40%), vitamin D (92%) and vitamin B12 (25%), and also iron (44%) and folate (18%). Normocalcaemic vitamin D insufficiency with secondary hyperparathyroidism was present in 18%. Iron and transferrin levels were associated with age, sex and estimated glomerular filtration rate. Vitamin K levels were associated with age, and inversely with BMI and diabetes mellitus; and PIVKA-II with smoking, triglycerides and liver function markers. Vitamin D levels were associated with statin use and prescription of supplements and inversely with BMI. Vitamin B12 levels were associated with ethnicity and HbA1c.. Micronutrient status shows differing relationships with age, gender and BMI. Vitamin K insufficiency was present in 40% and not related to deficiencies in other vitamins or micronutrients. Vitamin D and vitamin K supplementation should be considered prebariatric surgery in patients with diabetes or severe insulin resistance.

Topics: Adolescent; Adult; Aged; Bariatric Surgery; Female; Humans; Male; Micronutrients; Middle Aged; Obesity, Morbid; Preoperative Period; Prevalence; Prospective Studies; Vitamin D Deficiency; Vitamin K; Vitamin K Deficiency; Vitamins; Young Adult

Rivaroxaban is a direct factor Xa inhibitor, which is rapidly absorbed in the upper gastrointestinal (GI) tract. In large trials, it has been shown to be effective and safe in VTE treatment. However, in these trials patients with morbid obesity were not reported and it is unknown if the standard dosage of 20 mg rivaroxaban is sufficient for bariatric patients, especially after bariatric surgery, which may impact the resorption of rivaroxaban. We report the case of a bariatric patient with high venous thromboembolism risk and instable INR after recent bariatric surgery, who was switched from Vitamin-K antagonists to rivaroxaban. After intake of 20 mg rivaroxaban, plasma concentration were repeatedly measured until 3 h after the second dose using a commercially available chromogenic aXa-assay. Furthermore, INR and aPTT were measured. Peak concentrations of 224.22 ng/ml were observed. After 6 h, plasma concentration decreased to 86.9 ng/ml and remained stable until 12 h (86.32 ng/ml). After 24 h, a trough level of 35.54 ng/ml was observed. The patients INR did immediately increase and remained significantly elevated throughout the day with a slow decrease. Since peak values of rivaroxaban plasma concentrations were in the expected range of published data, we conclude that resorption of rivaroxaban was immediate and not significantly impaired by bariatric surgery of the upper GI tract. Consequently, no dose adjustments seem to be necessary in this high-risk population.

Topics: Adult; Anticoagulants; Bariatric Surgery; Female; Humans; International Normalized Ratio; Morpholines; Obesity, Morbid; Rivaroxaban; Thiophenes; Venous Thromboembolism; Vitamin K

Bariatric surgery has become a common therapeutic approach for severe obesity, in case of unsuccessful behavioural and/or medical interventions. During the past years, the number of obese women who underwent bariatric surgery in childbearing age has progressively increased. We report a case of vitamin K deficiency, due to maternal biliopancreatic diversion, resulting in a symptomatic clinical presentation in the mother and in a hypocoagulable state in her neonate.

Topics: Bariatric Surgery; Biliopancreatic Diversion; Blood Coagulation Tests; Female; Humans; Infant, Newborn; Male; Obesity, Morbid; Pregnancy; Pregnancy Complications; Vitamin K; Vitamin K Deficiency Bleeding