Associations of Blood Pressure with Functional and Cognitive Changes in Patients with Alzheimer's Disease

Abstract

Background: Midlife hypertension followed by late life hypotension resulting from neurodegeneration increases amyloidogenesis and tauopathy. Methods: Consecutive outpatients with late-onset Alzheimer's disease (AD) at various stages and their respective caregivers were assessed for score variations in 1 year of tests assessing caregiver burden, functionality and cognition according to blood pressure (BP) variations and APOE haplotypes, while also taking into account differential effects of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, β-blockers, calcium channel blockers, diuretics, or no antihypertensive medication on score changes. The diagnosis and treatment of arterial hypertension followed the JNC 7 report. Results: Variations in systolic BP (-11.76 ± 17.1 mm Hg), diastolic BP (-4.92 ± 10.3 mm Hg) and pulse pressure (-6.84 ± 12.6 mm Hg) were significant after 1 year (n = 191; ρ < 0.01). For APOE4+ carriers, rises in systolic or diastolic BP improved Clinical Dementia Rating Scale Sum of Boxes scores (ρ < 0.04), with marginally significant improvements in Mini-Mental State Examination scores resulting from risen systolic (ρ = 0.069) or diastolic BP (ρ = 0.079), and in basic independence only regarding risen diastolic BP (ρ = 0.055). APOE4- carriers resisted any functional or cognitive effects of BP variations. No differences were found regarding any antihypertensive class for variations in BP or any test scores, regardless of APOE haplotypes. Conclusions: Targeting mild BP elevations brings better functional and cognitive results for APOE4+ carriers with AD.