Wisconsin registry for Alzheimer’s prevention: Prospective cohort study of preclinical AD

Abstract

Adult children of persons with Alzheimer's disease (AD) are at increased risk of developing AD due to hereditary, environmental and health risk factors shared with affected parents. Prospective studies of middle-aged adult children of persons with AD provide an opportunity to characterize early cognitive and neurobiological changes consistent with pre-clinical AD and to identify health and lifestyle variables that influence disease trajectory. Knowledge of factors that influence the development of the AD syndrome is essential if we are to develop strategies for early intervention and prevention of AD. To determine the neuropsychological profile, apolipoprotein ϵ (APoE) genotype and demographic, health and lifestyle characteristics of a cohort of adult children of persons with AD. To date, 471 adult children (ages 40–65) have been recruited into the Wisconsin Registry for Alzheimer's Prevention (WRAP) and have undergone extensive neuropsychological testing, APoE genotyping and health assessments. Entry into WRAPrequires that an adult child provide either autopsy reports or medical records that must be reviewed to confirm the diagnosis of definite or probable AD in the parent. Preliminary results of our first wave of data assessment indicate the following: The cohort has a mean age of 53, 71% are women and 45% have an APoE ϵ4 allele. The neuropsychological performance of APoE ϵ4 carriers and APoE ϵ4 non-carriers at baseline did not differ. Homocysteine levels were negatively correlated with verbal memory when controlling for age, education and gender, and WRAP participants taking statins had higher verbal fluency scores. Exercise and moderate alcohol consumption were positively correlated with performance on several cognitive measures. The adult children of persons with AD have an increased prevalence of APoE ϵ4 allele, making them a high-risk group for developing AD. Our finding that the neurocognitive performance of ApoE ϵ4 carriers and non-carriers is not different at baseline suggests that this is an ideal population to follow longitudinally as cognitive changes develop in future years. The finding that lifestyle and vascular risk factors are correlated with baseline cognitive performance raises the question about their influence on the future risk of developing AD.