Executive functions and information processing in patients with type 2 diabetes in comparison to pre-diabetic patients

BACKGROUND: Diabetes is associated with cognitive decline or dementia. The purpose of this study was to assess the executive functions and information processing in patients with type 2diabetes in comparison to pre-diabetic patients and normal subjects in Endocrine and Metabolism Research Center of Isfahan City from April to July 2011. METHODS: The sample consisted of 32 patients with type 2 diabetes, 28 pre-diabetic patients and 30 healthy individuals. Executive functions were assessed by Wisconsin Card Sorting Test (WCST). Information processing was assessed by Paced Auditory Serial Addition Test (PASAT) and sub tests of Wechsler Adult Intelligence Scale-Revised (WAIS-R). RESULTS: There was a significant difference among 3 groups, after the variables of age, sex and academic status were controlled (p ≤ 0.001). The pairwise comparisons of executive functions among three groups suggest a significant difference between diabetic and normal groups in WCST (perseveration) p = 0.018, and significant difference between diabetic and pre-diabetic patient in WCST (perseveration) p = 0.019. But there was no difference between three groups in WCST (category) and WCST (conceptual responses). The pairwise comparisons of information processing among three groups, suggest a significant difference between diabetic and normal groups in PASAT3". PASAT2", and Symbol coding (P = 0.003, P = 0.009, and P = 0.001, respectively). There was a significant correlation between demographic variable (FBS, HbA1c) and Symbol coding p = 0.05, p = 0.01 respectively) and significant correlation between (cholesterol) and WCST (conceptual responses) p = 0.05. The other variables were not correlated. CONCLUSION: There were significant differences in executive function and information processing in patients with type 2 diabetic and normal individuals. Thus, monitoring neuropsychological status besides controlling levels of blood sugar in these patients is important.