Risk factors associated with cognitive decline in the elderly with type 2 diabetes: pooled logistic analysis of a 6-year observation in the Japanese Elderly Diabetes Intervention Trial

Abstract

Aim: Considerable attention has been paid to the association between type 2 diabetes mellitus (T2DM) and cognitive dysfunction in the elderly. T2DM is often comorbid with several other metabolic disturbances, including hypertension and dyslipidemia. These comorbid diseases might be associated with cognitive impairment. Many clinical indices should be included as variables for the association with cognitive decline. In the current study, we tried to identify the associated factors with cognitive decline during a 6-year period in elderly T2DM considering the changes in the clinical indices during the follow-up period.

Methods: The subjects in the present study were 63 Japanese Elderly Interventional Trial participants who were administered the Mini-Mental State Examination at baseline, at the third year, and at the end of the 6-year follow-up period. We applied the pooled logistic analysis method to consider the changes in clinical indices during the observation period and tried to identify the factors associated with cognitive decline during the 6 years in elderly type 2 diabetics using repeated measured data for glycated hemoglobin A1c, blood pressure and serum lipids.

Results: In the current study, low high-density lipoprotein-cholesterol and higher diastolic blood pressure were significantly associated with cognitive decline by pooled logistic analysis in the 6-year observation of older diabetic subjects. Higher glycated hemoglobin A1c had a tendency toward association with cognitive decline.

Conclusion: The results suggest that comprehensive management of diabetes, including dyslipidemia and hypertension, might contribute to the prevention of declines in cognitive function in older diabetic patients.