Abstract 83: Long-Term Blood Pressure Trajectories and Stroke Risk
Background— Previous studies have used blood pressure (BP) measurements at a single point in time to predict future CVD outcomes. We hypothesize that long-term BP trajectories are associated with stroke risk.
Methods— Data from 4 diverse cohorts were pooled. Each had 3+ exams where BP was ascertained and adjudicated stroke events. BP was classified into 5 categories:  ideal BP (<120/<80, no meds);  elevated BP (120-139/80-89, no meds);  controlled hypertension (<140/<90, treated);  uncontrolled hypertension (≥140/≥90, treated); and  untreated hypertension (≥140/≥90, no meds). BP trajectories were identified using group-based trajectory modeling. A cox proportional hazards model was used to assess BP trajectories as predictors of stroke occurrence adjusted for sex, race and cohort.
Results— This study included 13,028 participants (52% female, 93% White, avg baseline age 53.5 yrs). Six unique BP trajectories were identified (see figure). The ideal BP trajectory (group 1) included 19.4% of the population, 18.4% experienced modest age-related increases in BP (group 2), 36.7% developed hypertension but it remained under control (group 3), 14.2% experienced an early period of uncontrolled hypertension but later maintained control (group 4), 5.9% developed hypertension early in middle-age which remained untreated until later in life (group 5), and 5.3% developed hypertension later in life but it remained untreated (group 6 ). BP trajectory was significantly associated with risk for stroke even after adjustment for demographic characteristics. As compared to the ideal BP trajectory, groups 3, 4, 5 and 6 had elevated risk for stroke, HR (95% CI) 1.55 (1.33-1.81), 3.00 (2.45-3.69), 2.99 (2.39-3.75) and 2.18 (1.76-2.71), respectively.
Discussion— Long-term trends in BP are associated with the risk for stroke. Risk prediction algorithms should take long-term BP trajectories into account in order to identify individuals at high risk for stroke.
- © 2012 by American Heart Association, Inc.