Diabetes mellitus and cognitive functioning in a Serbian sample

Introduction: Diabetes is associated with cognitive impairments, particularly in executive functioning and memory. Aim: The aim was to describe cognitive functioning in Type 1 (T1DM) and Type 2 (T2DM) diabetes compared to healthy controls in a Serbian sample. Method: We studied 15 patients with adult onset T1DM (age range 19-60 years), 37 patients with T2DM (age range 50-77 years), and 32 healthy controls (28-78 years). All participants underwent comprehensive neuropsychological assessment. Results: T2DM subjects exhibited poorer performance than healthy controls in global cognitive performance, as well as verbal learning and memory. After correcting for multiple comparisons, follow-up examination of individual tests showed significantly poorer performance only on Trail Making Test Part B (TMT-B). Effect sizes for T2DM versus healthy controls ranged from medium to large for several cognitive variables, while comparisons between T1DM and the other two groups tended to yield much smaller effects. Conclusion: T2DM is associated with poorer cognition, particularly in executive functions, learning/memory, and global cognition. Lack of group differences may be due to use of an adult onset T1DM sample, relatively young age of our T2DM sample, or characteristics of healthy control subjects in our Serbian sample.