Background and aims: Diabetes and impaired fasting glucose, as well as cognitive impairment, are common in the elderly. Although several cross-sectional studies have demonstrated the influence of diabetes on cognitive impairment, only a few longitudinal studies have assessed the relationship between diabetes, impaired fasting glucose and cognitive decline in non-demented elderly community dwellers, by means of extensive neuropsychological batteries. The present study assesses the relationship between baseline diabetes, impaired fasting glucose (IFG) and 2- year evolution of memory, attention and executive performance in a sample of non-demented elderly subjects.
Design: Population-based cohort study [(PROgnostic indicator OF cardiovascular and cerebrovascular events (PROOF)].
Participants: One hundred and sixty-three community dwellers aged 65 years without dementia at recruitment.
Main outcome measures: Memory, attention and executive performance.
Results: A significant association was observed between baseline diabetes mellitus and a higher 2-year decline in the Trial Making Test B and Stroop test exploring attention and executive function. This effect remained significant after adjusting for age, gender, education, anxiety and depressive symptoms, as well as other cardiovascular risk factors (F=2.41; p=0.007). Instead, no relationship was observed between IFG and cognitive decline.
Conclusions: Our study showed that, in a sample of elderly non-demented community dwellers, diabetes mellitus (but not IFG) is associated with a higher decline in selective attention and executive functioning. These results emphasize the importance of detecting and man- aging diabetes and impaired fasting glucose, in order to prevent cognitive impairment and dementia.