Pre- and postoperative nutritional deficiencies in obese patients undergoing laparoscopic sleeve gastrectomy

Laparoscopic sleeve gastrectomy (LSG) has been identified as an innovative surgical approach for the treatment of obesity and is increasingly applied worldwide. However, data on outcome of LSG regarding nutrient deficiencies, protein status, and body composition are scarce.

Obese subjects (54; f:m = 4:1) scheduled for LSG were included in this study. Micronutrient analysis, protein status assessment, and bioimpedance measures were performed before and 1, 3, 6, and 12 months after LSG.

In 51% of the subjects, at least one micronutrient deficiency was found prior to surgery. Baseline concentrations were below normal for 25-OH vitamin D (27%), iron (29%), vitamin B6 (11%), vitamin B12 (9%), folate (6%), and potassium (7%). Frequencies of deficiencies for vitamin B12, folate, iron, and vitamin B6 tended to increase following LSG within the first year after intervention. Also, parameters of protein status (albumin, transferrin, cholinesterase, and total protein) decreased. After surgery, bioimpedance measures indicated a reduction of total body fat, but also of body cell mass.

Preoperative micronutrient deficiencies were common in morbid obese individuals scheduled for LSG. LSG had a modest effect on micronutrient status by further reducing iron, vitamin B12, vitamin B6, and folate within the first year after intervention. Our data suggest that especially obese patients with preoperative deficits require control and supplementation of micronutrients and protein in the postoperative period.