Background: Vitamin D deficiency is associated with obesity and type 2 diabetes mellitus (T2DM), although the use of circulating Vitamin D levels as a predictor of weight loss induced T2DM remission is unclear. Therefore, the aim of this study was to analyze whether pre-bariatric surgery vitamin D levels may predict T2DM outcomes 12 months post-SG.

Method: A cohort of 220 obese participants (74.5% female) with T2DM (Age: 50±9.5yr, BMI: 51.4±7Kg/m2; n=103) and without T2DM (Age: 46±9yr, BMI: 53.5±6.5Kg/m2; n=117) undergoing SG participated in an ethics approved study in a single bariatric centre in the UK. Patient anthropometric and biochemical data including vitamin D were collected at baseline and 12 months post-SG; no vitamin D supplementation at baseline was given.

Results: Baseline vitamin D levels inversely correlated with baseline BMI (P<0.001, r=-0.35). Age, pre-op weight loss and vitamin D levels were correlated with HbA1c 12 months post-SG (P<0.001, r=0.28, P<0.001, r=-0.25 and P<0.05, r=-0.19). Furthermore, baseline vitamin D levels predicted levels of HbA1c post-surgery following adjustment for pre-op weight loss and age. Within the T2DM group, those that achieved T2DM remission 12 months post-SG (49.5%; n=51) had a higher baseline vitamin D compared to those not in remission (43.5±23.8 vs. 33±19nmol/L; P<0.05), with no significant differences between the two groups in baseline BMI, hypertension, pre-op weight loss or excess weight loss (EWL). Interestingly, patients with higher pre-surgical Vitamin D levels also had significantly lower BMI (P<0.005) and higher % EWL (P<0.05) 12 months post-surgery.

Conclusion: Baseline Vitamin D levels appear to be an independent indicator for successful T2DM remission and weight loss, 12 months following SG. The use of baseline Vitamin D levels may help us predict those more likely to do well and prioritize post-surgery support to achieve success for all participant groups.

Disclosure

A. Aladel: None. M.K. Piya: None. S. Azharian: None. M. Christian: None. V. Menon: None. P.G. McTernan: None.

Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered. More information is available at http://www.diabetesjournals.org/content/license.