Keywords
Metformin; Malabsorption; Diabetes mellitus; vitamin B12
Abstract
Type 2 Diabetes Mellitus (DM2) is a chronic morbidity with worldwide high prevalence. Its treatment includes many therapies such as drugs and lifestyle changes. Bariatric surgery has been widely used for the treatment of severe obesity and has shown improvement in DM2 control. However, it has important nutritional complications such as iron, calcium, vitamin D and vitamin B12 malabsorption. Vitamin B12 is found in animal derived foods and its deficiency is generally manifested by features of megaloblastic anemia with possible neurologic manifestations. Moreover, its deficiency also constitutes an important risk factor for cardiovascular diseases. Metformin is the first line drug in the treatment of DM2 and its main side effects are gastrointestinal, such as nauseas and diarrhea. Besides, its use has been associated with vitamin B12 malabsorption and deficiency. Since it has positive impact on body weight, metformin is commonly used by patients in pre and post-operative of bariatric surgery. This is a cross-sectional study based on medical record information that analyzed B12 serum levels and other variables in Obese patients with impaired glucose tolerance, in use or not of metformin, attended between 2010 and 2012 in a center specialized in clinical and surgical treatment of obesity. Sixty six patients were included in the study. Twenty (30%) of them were in use of metformin and had lower vitamin B12 levels when compared to those who were not in use of this drug. Also, these levels were negatively correlated with metformin time of use and dosage. Thus, patients in use of metformin require special attention in both pre and post-operative of bariatric surgery regarding the deficiency of vitamin B12.
Citation
Short F, Daltro C, Drummond M, Daltro C, Rios A and Vinhas L. Metformin Use is Associated with Lower Levels of Vitamin B12 in Obese Patients. SM J Food Nutri Disord. 2016; 2(1): 1009.