Abstract P190: Association of Hypertension According to New ACC/AHA Blood Pressure Guidelines with Incident Dementia in the Atherosclerosis Risk in Communities Cohort

Abstract

Background: Although associations between hypertension in mid-life and the development of dementia and cognitive decline have been established, the impact of the new 2017 ACC/AHA guidelines on dementia risk at the population level has not been evaluated. Objectives: To assess the association of hypertension categories with the risk of incident dementia and to calculate the population attributable fraction (PAF) for dementia from hypertension categories according to the 2017 ACC/AHA guidelines, and compare these associations with hypertension defined according to JNC7. Methods: We studied dementia-free participants recruited to the Atherosclerosis Risk in Communities (ARIC) cohort in 1987-89. Hypertension was defined by 2003 JNC7 and 2017 ACC/AHA guidelines using blood pressure measured at baseline; participants using antihypertensive medication were included in hypertension stage 2 for both sets of guidelines. Dementia was defined using adjudicated consensus diagnoses at visit 5 (2011-13), informant telephone interviews, and ICD-9 codes from hospitalizations and death certificates through 2013. Cox proportional hazards regression models estimated hazard ratios (HR) and 95% confidence intervals (CI) by hypertension categories, adjusting for potential confounders, including sociodemographic, lifestyle and clinical variables. PAF of dementia by hypertension category was calculated using rate ratios from Poisson regression and the prevalence of the risk factor in the population. Results: Among 13,971 participants followed for a median of 23.0 years, 1381 cases of dementia were identified. Prevalence of elevated BP (systolic BP [SBP] 120-129 and diastolic BP [DBP] <80), hypertension stage 1 (SBP 130-139 or DBP 80-89) and hypertension stage 2 (SBP ≥140 or DPB ≥90) according to 2017 ACC/AHA categories was 13%, 15% and 44%, respectively. Corresponding HR (95%CI) compared to normal BP were 1.35 (95%CI 1.12, 1.61), 1.28 (1.07, 1.52) and 1.36 (1.18, 1.57), respectively. PAF (95%CI) of dementia from hypertension categories were 3% (1%, 5%), 3% (1%, 5%) and 9% (4%, 14%). PAF using JNC7 categories were similar to 2017 ACC/AHA: 6% (3%, 9%) for prehypertension (SBP 120-129 or DBP 80-89), 0% (-2%, 2%) for hypertension stage 1 (SBP 140-159 or DBP 90-99), and 9% (5%, 13%) for hypertension stage 2 (SBP ≥160 or DBP ≥100). Conclusions: Risk of dementia was increased across categories defined by the new ACC/AHA hypertension guidelines. However, the population impact on dementia incidence using 2017 ACC/AHA was similar to the impact of JNC7. These results suggest that the new criteria for diagnosis of hypertension will not increase the number of persons in whom hypertension could be reasonably labeled as a risk for dementia.