Prevalence of Micronutrient Deficiencies Prior to Bariatric Surgery: Tehran Obesity Treatment Study (TOTS)

Abstract

Background: Micronutrient deficiencies are major concerns after bariatric surgery, although these conditions often go undiagnosed pre-surgery.

Objective: To assess pre-surgery micronutrient status of an Iranian population of morbidly obese candidates of bariatric surgery in a cross-sectional study.

Methods: A cross-sectional analysis of 2008 candidates for bariatric surgery, aged 15-65 years, with either body mass index (BMI) ≥ 40 kg/m² or 30 < BMI < 35 kg/m² with a medical comorbidity was conducted. In order to determine the micronutrient status of participants, blood samples were collected to assess serum concentrations of vitamins (B12 and D), minerals (copper, calcium, phosphate, and zinc), and iron profiles (total iron binding capacity, iron concentration, ferritin, and iron saturation), according to standard protocol.

Results: The mean age and BMI of patients (79.3% female) were 37.8 years and 44.8 kg/m², respectively. Deficiencies were found for 25(OH) D (53.6%), vitamin B12 (34.4%), serum iron (10.2%), and low levels of hemoglobin (16.6%). The prevalence of other deficiencies were all below 10%. Body mass index had a negative correlation with iron, calcium, vitamin B12, and 25(OH) D and was positively correlated with copper.

Conclusion: Micronutrient deficiencies, including vitamin D, vitamin B12, and iron, are commonly found among morbidly obese subjects who are potential candidates of bariatric surgery.

Keywords: Bariatric surgery; Metabolic surgery; Micronutrient deficiency; Prevalence.