Micronutrient deficiencies following bariatric surgery: a comparative analysis between sleeve gastrectomy and Roux-en-Y gastric bypass.

ABSTRACT Objective: to compare the prevalence of micronutrient deficiencies in patients submitted to sleeve gastrectomy (SG) and Roux- en-Y gastric bypass (RYGB). Methods: this is a comparative study of 576 patients submitted to bariatric surgery, 338 to SG and 238 to RYGB, and evaluated for hemoglobin, iron, ferritin, zinc and vitamin B12 serum levels. We performed these dosages in the preoperative period and at three, six, 12 and 24 months after surgery, for analysis and comparison of micronutrient deficiencies among the techniques. Results: the SG group consisted of 48 men and 290 women, with a mean BMI of 39.4±2.6kg/m2, and a mean of age of 37.2±11 years; the group RYGB consisted of 77 men and 161 women, with mean BMI 42.7±5.9kg/m2, and a mean age of 41.9±11.1 years. After 24 months, hemoglobin deficiency was present in 24.4% of the patients submitted to SG and in 40% of the RYGB individuals (p=0.054); iron deficiency was present in 6,6% of SG patients and in 15% of RYGB ones (p=0.127); ferritin deficiency occurred in 17.8% of the SG group and in 23.7% of RYGB one (p=0.399); the Zinc deficiency incidence was 6.6% in SG and 30% in RYGB (p=0.002); and B12 deficiency took place in 6.6% the SG patients and in 8.7% of RYGB ones (p=0.844). Conclusion: patients undergoing SG had serum levels of iron and zinc superior to the ones undergoing RYGB, the prevalence of the latter micronutrient deficit being significantly higher in the RYGB group.