MODIFIABLE RISK FACTORS FOR PREVENTION OF DEMENTIA IN MIDLIFE AND LATE LIFE: THE LIBRA INDEX
Background:Lifestyle factors have been associated with obtaining and maintaining a healthy brain, but the exact role of these factors in the development of Alzheimer's disease dementia remains unknown. Aim of the study was to investigate whether in individuals with subjective cognitive impairment (SCI) and Mild Cognitive Impairment (MCI) smoking, alcohol consumption, sleep, physical activities and cognitive activities were associated with key biomarkers of AD, i.e. amyloid positivity and hippocampal atrophy. Secondly, we examined in individuals withMCI, whether these factors have a modulatory effect on the predictive accuracy of hippocampal atrophy and CSF amyloid positivity for developing ADtype dementia. Methods:We selected subjects with SCI (n1/4123) and MCI (n1/4274) from the European DESCRIPA study for the VPH DARE project. Amyloid pathology in cerebrospinal fluid (CSF) was assessed with ELISA assay <550 pg/mL) in 174 subjects. Hippocampal atrophy was measured using LEAP in 208 subjects. Information on the following lifestyle factors was collected by clinical interview: smoking, alcohol consumption, sleep (i.e. any sleep problems) physical activities (i.e. cycling, walking, gym or other sports several times a week) and cognitive activities (i.e. reading, listening to the radio, playing games or chess several times a week) We performed logistic regression and Cox regression analyses adjusted for centre, age, sex, education and diagnosis. Results:Cognitive activity, physical activity, sleep and smoking did not correlate with amyloid positivity or hippocampal volume. Alcohol consumption was associated with a lower risk for amyloid positivity (OR1/40.44, p<.05) Furthermore, in individuals with only MCI and with normal hippocampal volumes, alcohol consumption had a protective effect on conversion to AD type dementia (HR1/40.31, p<.05).Conclusions:In subjects with SCI andMCI, lifestyle factors have no impact on key AD biomarkers. However, alcohol consumption may act as a protective factor for amyloid pathology, and in subjects withMCI alcohol consumption may be protective for conversion to AD.
Alzheimer's Dementia