Introduction: Bariatric surgery is an important treatment option for morbid obesity. The current guidelines recommend testing and supplementation of vitamin D postoperatively. The aim of our study was to assess the need for preoperative proactive supplementation of vitamin D. Methods All patients who had restrictive bariatric surgery (laparoscopic gastric bypass or sleeve gastrectomy) between January 2010 and June 2011 were included. Data was collected retrospectively from computerised lab records and surgical database. Vitamin D checked any time preoperatively and within 1 year post operatively was taken into account.
Results: 65 patients had been operated during the study period Pre-operative characteristics: 78.5% females; Mean age 43.3 years (2668); Mean weight 134.6 kg (93.6210); Mean BMI 48.1 (3961) Diabetes in 27%; Ischemic heart disease 3%: Dyslipidemia 34%; Hypertension 35%; Painful arthritis 35%; sleep apnoea 3% 44(68%) had Vitamin D checked pre-operatively; 23 (52%) had significant vitamin D deficiency (<50 nmol/l). Vitamin D levels negatively correlated with BMI (r=−0.3). PTH positively correlate with the BMI (r=0.19). Of the 50 patients who had both PTH and Vitamin D checked, 16% had normal PTH despite Vitamin D deficiency. Post operative characteristics: All patients were started on Calcium, vitamin D and multivitamin supplements postoperatively. 51(72%) had Vitamin D checked post-operatively; 16 (31%) still had significant vitamin D deficiency. 31 patients had vitamin D checked pre and post operatively: 14 normal preoperatively (13 remained normal postoperatively, 1 developed deficiency) and 17 deficient preoperatively ( 9 remained deficient post operatively despite supplementation, 8 normalized).
Conclusions: Vitamin D deficiency is highly prevalent among patients with obesity referred for bariatric surgery. PTH is not a good marker to predict this. Pre-operative assessment of vitamin D status and active treatment would be beneficial rather than routine post operative supplementation as absorption may not be very predictable.
Declaration of interest: There is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported.
Funding: No specific grant from any funding agency in the public, commercial or not-for-profit sector.