Endocrine Abstracts

Rationale: Patients with morbid obesity may have vitamin D deficiency and bariatric surgery may exacerbate it due to various factors such as lack of dietary compliance, reduced intake, malabsorption, etc.

Objective: To study the prevalence of vitamin D deficiency in patients with morbid obesity before and after bariatric surgery and its relationship with other laboratory parameters.

Methods: A retrospective study of 72 morbidly obese patients before and 1 year after surgery (bypass or sleeve). We collected data about: age, sex, previous comorbidities, physical examination, impedance testing, and laboratory parameters (25-hydroxyvit D, iPTH, Ca, HbA1c, total cholesterol, LDL, HDL, triglycerides, uric acid, and leptin).

Results: The mean age of patients was 45.84±10.39 years, 78.4% women. Pre-and postoperatively BMI: 51.51±8.11 and 33.36±5.21 (P 0.00). One year after surgery there were significant decreases in HbA1c, TC, LDL, triglycerides, uric acid, leptin, and HDL increase. Mean serum 25-OH vit D pre and post were: 16.96±7.87 vs 22.53±12.44 (P 0.013) and iPTH: 16.9±43.97 vs 41.79±1, 89 (NS). The percentage of vitamin D deficiency (<20 ng/ml) were pre and post: 71.8 vs 44.9% (P 0.04) and hyperparathyroidism 19.4 vs 14.6% (NS). Vitamin D levels negatively correlated with preoperative age, body fat percentage and iPTH. Vitamin D levels negatively correlated with postoperative BMI, leptin, total cholesterol, and HbA1c.

Conclusions: Patients with morbid obesity have vitamin D deficiency in 71.8% of cases preoperatively, which should lead us to measure 25OH vitamin D levels routinely in patients with morbid obesity.

After the surgical procedure, despite supplementation with vitamin D, patients maintain a high percentage of vitamin D deficiency (44.9%) and elevated iPTH.