Variations in Oral Vitamin and Mineral Supplementation Following Bariatric Gastric Bypass Surgery: A National Survey

Background Bariatric surgery (including gastric bypass) is associated with long-term deficiencies in vitamins and minerals, which may have deleterious effects on physiology. The American Association of Clinical Endocrinologists’ (AACE) guidelines regarding post-operative vitamin supplementation have recently been endorsed by the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO). Supplements have cost implications. Non-branded multivitamins may have similar compositions to branded multivitamins, but at a lower cost. This study assesses multivitamin supplementation following bariatric gastric bypass in England against AACE guidelines. It also examines the composition and cost of branded and non-branded multivitamins. Methods Micronutrient amounts in common multivitamin preparations were obtained from product literature. Costs were collected from a standard retailer. To determine vitamin prescribing patterns, the 37 NHS hospitals performing bariatric gastric bypasses in England were contacted. Practice was assessed against AACE guidelines. Results All non-branded multivitamins met AACE guidelines for composition. Most had similar compositions to branded multivitamins, and all were cheaper. There was no standard practice regarding post-operative supplementation among the 35 responding hospitals. Only 7/35 (20 %) hospitals followed the guidance for two-tablet doses of multivitamins. Immediately post-operatively, 25/35 (71 %) hospitals administered calcium carbonate and vitamin D (none recommended calcium citrate, as recommended by AACE to improve absorption), and only 9/35 (26 %) hospitals recommended iron to all patients. Conclusion Most non-branded multivitamins are lower cost alternatives to branded multivitamins, with similar compositions. The AACE recommendation for two-tablet doses of multivitamins is not being met by most English centres. Calcium and iron supplementation is also inadequate.