Coffee drinking in middle age is not associated with cognitive performance in old age.

BACKGROUND The lack of effective disease-modifying treatments highlights the need for research on the prevention of dementia. It has been suggested that coffee has a protective effect on cognitive performance in old age, but only some of the previous studies have shown this association. OBJECTIVE The aim of our study was to analyze the potential association between coffee drinking in middle age and cognitive performance in old age in a large sample of Finnish twins. DESIGN Coffee consumption and other baseline variables of 2606 middle-aged Finnish twins were assessed in 1975 and 1981 by postal questionnaires. After the median follow-up of 28 y, their cognitive status was measured by using a validated telephone interview questionnaire. RESULTS Coffee consumption was high and associated with educational level and several other baseline variables. After adjustment for these variables, linear regression analysis showed that coffee consumption was not an independent predictor of cognitive performance in old age (beta = -0.12 test score units per coffee cup; 95% CI: -0.27, 0.04). No consistent differences in coffee consumption and cognitive score were observed within discordant twin pairs. Also, coffee drinking did not affect the risk of mild cognitive impairment or dementia. CONCLUSIONS Coffee drinking is associated with many sociodemographic and health variables, but our results do not support an independent role of coffee in the pathogenesis of cognitive decline and dementia.