Treatment of vascular risk factors is associated with slower decline in Alzheimer disease

BACKGROUND: There is growing evidence that vascular risk factors (VRF) contribute to cognitive decline. Whether their treatment can slow down the progression of Alzheimer disease (AD) remains unsettled. The aim of this observational study was to evaluate whether the treatment of VRF is associated with a slower cognitive decline in patients who have AD without cerebrovascular disease (CVD). METHODS: We recruited 301 consecutive patients who had AD without CVD (mean age 71.7 years; 69.4% women; first Mini-Mental State Examination MMSE mean score 21.6; mean follow-up 2.3 years), who had attended a memory clinic between 1997 and 2003. VRF sought were high blood pressure, dyslipidemia, diabetes mellitus, tobacco smoking, and atherosclerotic disease. Only 21 patients (7.0%) had no VRF. Others were classified as having no VRF treated (n = 72; 25.7%), some VRF treated (n = 119; 42.5%), or all VRF treated (n = 89; 31.8%). We compared MMSE progression over time among these 3 groups using a mixed random effects regression model. RESULTS: Baseline MMSE scores were similar in the 3 groups. With adjustment for confounding factors, MMSE progression over time differed significantly between groups (p = 0.002). Patients with all their VRF treated declined less than those with none of their VRF treated. Those with some VRF treated tended to have an intermediate decline. CONCLUSIONS: In patients who have Alzheimer disease without CVD, treatment of vascular risk factors (VRF) is associated with a slower decline in Mini-Mental State Examination score. Randomized controlled trials are needed to confirm this association, but our data suggest that dementia should not prevent treatment of VRF.