IMPACT OF VITAMIN D DEFICIENCY ON COGNITIVE FUNCTIONS IN TYPE 2 DIABETIC PATIENTS

Objective. We hypothesized that vitamin D-deficient diabetic patients might demonstrate cognitive deficits and therefore investigated this association in patients with diabetes mellitus (DM). Methods. This study comprised 236 patients with type 2 DM (118 with vitamin D deficiency (less than 20 ng/mL) and 118 without vitamin D deficiency as the control group). All patients were outpatients in the endocrinology clinics of Baskent University, Turkey from 1 October 2013 to 31 January 2014 and, chosen in a randomized manner according to their application time. The serum vitamin D levels were measured and cognitive functions were evaluated using the Mini Mental Status Examination (MMSE). Results. The mean age in the study and control group was 57.02 +/- 7.30 and 58.92 +/- 7.58 years, respectively (p=0.051). The male:female ratio in the study and control group was 1.00:1.46 and 1.00:2.11, respectively. The study group was further divided into three subgroups: patients with mild, moderate, and severe vitamin D deficiency. The study outcomes revealed no significant relationship between the vitamin D deficiency level and the total score or subscores of the MMSE (p<0.05). Conclusions. These study results do not confirm the hypothesis that vitamin D deficiency unfavorably affects cognitive functions in patients with type 2 DM.