Cognitive functioning in older adults with type-2 diabetes, study from Southern India

Abstract

Background: Evidence suggests that type-2 diabetes mellitus (T2DM) is associated with cognitive impairment. There is a dearth of research on T2DM and cognition in older adults from India. We aimed to study the cognitive functioning of older persons with T2DM compared to healthy controls (HC) and understand the influence of illness characteristics and other associated comorbidity on cognitive functioning. Methods: One hundred eight older persons with T2DM and 107 HC matched for age, gender, and education were invited to participate in the study. Both groups were assessed using NIMHANS Neuropsychological Battery for the Elderly. Results: The mean age of the study group (T2DM and HC) was 66 (±5) years; 60% were male with an average of 12 years of formal education. More than 95% of the subjects were from an urban background and belonged to either middle or upper socioeconomic status. Compared to HC, persons with T2DM performed poorly on all memory tasks (both verbal and visual memory), constructional ability, verbal fluency, working memory, and attention tasks. Lower educational levels and the presence of T2DM were the strongest predictors of poorer cognitive performance in the study group. Conclusions: T2DM seems to affect cognitive domains differently. In this study, memory was the most affected cognitive domain, followed by executive functions and attention. Recent memory deficits could be a forerunner of early dementia. There is a need for longitudinal studies focusing on T2DM and cognition in the elderly from India, providing more insights into the early detection and prevention of dementia in this risk group.

Keywords

• aging
• cognition
• diabetes
• low- and middle-income country