Is Diabetes Associated With Cognitive Impairment and Cognitive Decline Among Older Women?

Abstract

OVER 33% of women and 16% of men 65 years and older will develop dementia during their lives, with many cases leading to functional decline, comorbid conditions, and the extensive need for health services.^1-3 Although the etiology of dementia is complex and some cross-sectional studies suggest that diabetes may lead to cognitive decline caused by hypoglycemia, hyperglycemia, hyperinsulinemia, or vasculopathy,^4-13 the results from the few prospective studies examining diabetes and change in cognitive function or incidence of dementia have been inconsistent.^14-18 Additionally, no large, population-based, prospective studies have evaluated the relationship between diabetes and change in cognitive function using repeated neuropsychologic tests over time. Similarly, few studies have addressed the relationship between diabetes duration and long-term cognitive decline. Because diabetes affects up to 18% of women and 20% of men 65 years and older,¹⁹ a significant relationship between diabetes and cognitive impairment would have important clinical and public health implications. We examined the relationship of diabetes and diabetes duration to cognitive decline during up to a 6-year follow-up in a prospective study of more than 9000 older women.