Abstract 45: The Association of Cumulative Systolic Blood Pressure With Cardiovascular Disease: Findings From the Lifetime Risk Pooling Project Cohorts

Abstract

Background: Blood pressure (BP) is a known risk factor for cardiovascular disease (CVD), but prior studies have predominantly focused on single measurements of BP. Previous studies which have examined longitudinal BP have been mostly limited to a single cohort and have examined BP during older age. Objective: To assess the association of cumulative systolic BP (SBP) in middle age with CVD using individual-level pooled data from 5 US community-based cardiovascular disease cohorts. Methods: Among participants from the Lifetime Risk Pooling Project, we defined the index date as the earliest SBP measurement taken within 45-65 yr of age with ≥2 previous SBP measurements during the prior 5 years. Multivariate Cox proportional hazards models, with and without current SBP, were used to assess the association of cumulative 5-years SBP (Cum5ySBP, defined as 4 quarters {q1to q4} of SBP mm Hg-years) with any CVD, coronary heart disease, stroke, and heart failure. Models were adjusted for age, sex, race, education, BMI, smoking status, diabetes, total cholesterol level, and use of hypertensive medications as well as index SBP. Results: The association of Cum5ySBP with CVD over an average of 12.9 years was assessed for 13,957 individuals (54.6% women; mean age: 59.6 yr). Cum5ySBP was significantly associated with CVD incidence, with higher risk as the Cum5ySBP increased {Cum5ySBP: HRq2: 1.34 (1.20-1.48), HRq3: 1.71 (1.55-1.90), and HRq4: 2.16 (1.95-2.40)} (Figure 1A). The Cum5ySBP remained significant even when index SBP was incorporated into the model {Cum5ySBP: HRq2: 1.12 (1.01-1.25), HRq3: 1.24 (1.10-1.39), and HRq4: 1.19 (1.03-1.37)} (Figure 1B), as well as when evaluated separately for each type of CVD event. Conclusions: Cum5ySBP is a significant risk factor of CVD, above and beyond current BP. The risk for any CVD component increased with increases in cumulative SBP. These findings emphasize the importance of early treatment for individuals with high BP in order to reduce the cumulative burden of SBP and ultimately prevent CVD outcomes.