Prevention of dementia by intensive vascular care (PreDIVA): a cluster-randomized trial in progress

Cardiovascular risk factors are associated with an increased risk of dementia. Treatment of hypertension and hypercholesterolemia is associated with a decrease in incident dementia. Whether interventions aimed at cardiovascular risk factors in late life also reduce dementia risk is unknown. Here, we report the outline of a pragmatic study that will attempt to answer this question and we describe the prevalence of cardiovascular risk factors in the target population.

We designed a large cluster-randomized trial with a 6-year follow-up in 3700 elderly subjects (70 to 78 y) to assess whether nurse-led intensive vascular care in primary care decreases the incidence of dementia and reduces disability. Secondary outcome parameters are mortality, incidence of vascular events, and cognitive functioning. Intensive vascular care comprises treatment of hypertension, hypercholesterolemia, diabetes and reducing overweight, smoking cessation, and stimulating physical exercise.

Baseline data of 1004 subjects show that 87% of the subjects have 1 or more cardiovascular risk factors and 44% have even 2 or more risk factors amenable to treatment. Seventy-nine percent of the subjects receiving antihypertensive medication still have a systolic pressure of >140 mm Hg.

In this older age group, the very high percentage of elderly subjects with cardiovascular risk factors illustrates the large window of opportunity for therapies directed to lower the cardiovascular risk and potentially also the risk for dementia.