Prevalence and associated factors of vitamin D deficiency after Roux-en-Y gastric bypass: A systematic review and meta-analysis

Abstract

Objects: To estimate the prevalence and associated factors of vitamin D deficiency (VDD) after Roux-en-Y gastric bypass (RYGB). Methods: PubMed, EMBASE, and CENTRAL were searched for relevant records from inception to March 17, 2023, using search terms: vitamin D, vitamin D3, vitamin D deficiency, hypovitaminosis D, gastric bypass, and RYGB. Studies were eligible for inclusion if they provided related data on VDD prevalence after RYGB. Results: Of 1119 screened studies, 72 studies involving 7688 individuals were enrolled in the final analysis. The prevalence estimates of VDD after RYGB were 42%. Subgroup analyses suggested the pooled prevalence of postoperative VDD was 35% for follow-up duration ≤1 year, 43% for >1 and ≤5 years, and 54% for >5 years. Meta-regression showed that VDD prevalence was positively correlated with follow-up time. Also, the prevalence was higher in studies with inadequate vitamin D supplementation than in those with adequate supplementation and in Asia population than in those from South America, Europe, and North America. Other factors associated with high VDD prevalence after RYGB included high presurgical VDD prevalence, non-compliant patients, and black populations. No significant association existed between VDD and alimentary length. Conclusion: VDD presented a high prevalence in patients following RYGB. It occurred more frequently with longer postoperative follow-up time. Population-specific vitamin D supplementation measures, targeted treatment for presurgical VDD, improved patient compliance, and periodical follow-ups were necessary to reduce VDD and other adverse outcomes.

Update on Micronutrients in Bariatric Surgery: A Comprehensive Systematic Review

“…It is worth noting that there were variations in the recommended vitamin D supplementation across the studies reviewed. 8 Stocker et al provided guidance on micronutrient intake for individuals who have undergone bariatric surgery. Their recommendations include supplementing with 5000-10,000 IU of vitamin A daily (10,000 IU for those who have undergone BPD-DS), at least 12 mg of vitamin B1 daily (preferably 50-100 mg), 350-1000 μg of vitamin B12 daily (or 1000 μg monthly via injection), and 3000 IU of vitamin D3 daily until blood levels of 25(OH)D reach above 30 ng/mL.…”