Endocrine Abstracts

Purpose: Obesity and/or bariatric surgery can be associated with micronutrient deficiencies. We studied whether there was a correlation between body mass index (BMI) and micronutrient levels pre- and post-bariatric surgery.

Methods: We performed a retrospective cohort study of 745 patients who underwent bariatric surgery in a Northwest England teaching hospital. Patients were recommended standard postoperative supplements consistent with national guidelines. Data on concentrations of folate, iron, vitamin B12 and vitamin D and BMI were collected from electronic patient records before surgery and at 4-,12-,24-,36- and 48-months of follow-up.

Results: The patients included 514 (69.0%) women; 496 (66.6%) underwent gastric bypass, 240 (32.2%) sleeve gastrectomy and 10 (1.3%) gastric band surgery. At baseline, mean±SD age was 47.0±10.5 years, weight 135.1±23.6 kg and BMI 51.2±7.7 kg/m²; folate was 8.0±3.9 µg/l, iron 12.2±4.6 µmol/l, vitamin B12 411.4±269.1 ng/l and vitamin D 32.6±24.1 nmol/l. BMI at baseline was inversely correlated with serum folate (coefficient, -0.221) and vitamin D (-0.269), and weakly correlated with vitamin B12 (-0.069) and iron (-0.077) concentrations Mean concentrations of folate, iron, vitamin B12 and vitamin D increased with supplementation at follow-up.

Conclusion: The continued increase in micronutrient concentration and weakening negative correlation found between BMI, folate and vitamin D after follow-up appointments indicates the effectiveness of micronutrient supplementation. Investigations into the effect of other variables on micronutrient concentrations post-bariatric surgery are necessary to comprehend the BMI–micronutrient relationship further.

Table of mean micronutrient concentration before bariatric surgery at follow-up.