Session Title: Alzheimer's Disease (AD) including Non-Cognitive Aspects
Presentation Date: Friday, March 14 – Saturday, March 15, 2009
MIDLIFE CARDIOVASCULAR RISK FACTORS, SMOKING, APOE STATUS AND RISK OF DEMENTIA AND COGNITIVE IMPAIRMENT
E. Rönnemaa, B. Zethelius, J. Sundelöf, M. Degerman-Gunnarsson, L. Lannfelt, L. Kilander
Uppsala University, Public Health and Caring Sciences/Geriatrics, Uppsala, Sweden
Aim: To evaluate the longitudinal associations of midlife cardiovascular risk factors and the subsequent development of dementia and cognitive impairment and the interaction with APOE e4 genotype.
Methods: The population-based Uppsala Longitudinal Study of Adult Men started 1970 when the 2322 participants were 50 years old. Investigations included determinations of blood pressure, serum cholesterol, glucose tolerance, body mass index and smoking. During a median follow-up of 31·6 years, 394 participants were diagnosed with any dementia or cognitive impairment. Associations were analysed using Cox proportional hazard models. All analyses were performed crude, adjusted for age and education level as well as stratified for APOE status.
Findings: Each risk factor was associated with an increase in risk of any dementia and cognitive impairment: [HR for 1SD increase 1.16 (95%CI 1·06-1·28)] for hypertension, [HR for 1SD increase 1.14 (95%CI 1·03-1·26)] for serum cholesterol, [HR for 1SD decrease 1.13 (95%CI 1.00-1·27)] for glucose intolerance, [HR for 1SD increase 1·11 (95%CI 1·00-1·23)] for body mass index and [HR 1.37 (95%CI 1·12-1·67)] for smoking. The hazard ratio of dementia and cognitive impairment for the presence of three or more risk factors was 1.31 (95%CI 1·12-1·67). Smoking was a significant risk factor only in subjects without the APOEe4 allele [HR 1.53 (95%CI 1.22-1·93)]. No significant associations between cardiovascular risk factors and pure Alzheimer's disease were found.
Interpretation: The presence of cardiovascular risk factors at midlife modestly increases the risk of late-life dementia and cognitive impairment. The risk of smoking is modified by APOE e4 genotype.