Long-term Nutritional Impact of Sleeve Gastrectomy

Background: Sleeve gastrectomy (SG) has become a predominant bariatric procedure throughout the world. However, the long-term nutritional impact of this procedure is unknown.

Objectives: To describe the nutritional deficiencies before and after SG and to analyze the influence of baseline weight on nutritional status.

Setting: University-affiliated tertiary care center.

Methods: All patients who underwent SG as a standalone procedure between 2008 and 2012 were included in this study. Patients were given multivitamin supplementation. Data were obtained from our prospectively maintained electronic database and are reported as mean ± standard deviation and percentage. Bivariate analyses were conducted to evaluate the influence of selected variables on outcomes.

Results: The mean age of the 537 patients was 48.0 ± 11.3 years, with an initial body mass index of 48.1 ± 8.7 kg/m. Excess weight loss and total weight loss were 56.2% and 28.0% at 1 year and 43.0% and 21.1% at 5 years, respectively (P<.0001). Percentage of follow-up was 74% at 5 years (n = 79). The mean follow-up time was 34.3 ± 17.2 months. Hypoalbuminemia was present in 1.1% preoperatively and 4.2% at 5 years (P = .0043), low ferritin levels in 8.6% and 37.8% (P<.0001), low vitamin B12 in 30.3% and 16.4% (P<.0001), low vitamin D 63.2% and 24.3% (P<.0001), and hyperparathyroidism in 23.4% and 20.8% (P<.0001). There was no significant difference in the prevalence of anemia over time (P = 0.4301). The prevalence of vitamin A insufficiency peaked from 7.9% preoperatively to 28.7% at 3 months (P<.0001) and returned to baseline thereafter. Baseline weight was negatively correlated with vitamin B12 and vitamin D.

Conclusion: Nutritional deficiencies are common in patients with morbid obesity before and after surgery. Preoperative supplementation and long-term nutritional follow-up are required to prevent nutritional deficiencies.