Abstract 19256: Predicting Exercise Systolic Blood Pressure and Heart Rate at 20 Years of Follow-up: Correlates in the Framingham Heart Study

Introduction: Blood pressure (BP) and heart rate (HR) responses to exercise may add prognostic information beyond their resting values. Many cardiovascular disease (CVD) risk factors are associated with exercise BP and HR cross-sectionally, but factors influencing exercise hemodynamics over the life-course are unknown. Methods: We assessed BP and HR in response to treadmill tests (6 minutes of the Bruce protocol) in a sample of 1231 Framingham Offspring participants who performed the treadmill test during two routine examinations: 1979-1983 (baseline) and 1998-2001 (follow-up). We included participants (55% women, mean age 39±8 years at baseline, 58±8 years at follow up) free of CVD and not taking beta-blockers or anti-hypertension medications at either exam. Baseline diabetes mellitus (DM) cases and individuals taking lipid-lowering medications at baseline were excluded due to small numbers. We related exercise hemodynamics at follow-up to baseline CVD risk factors and their interim changes, also adjusting for baseline exercise hemodynamics. Results: Compared with men, women experienced greater change in exercise hemodynamics at 20 y follow-up, relative to baseline exercise hemodynamics (see Table 1). Baseline blood lipid levels, resting SBP and HR, and smoking status were associated with greater exercise SBP at follow-up. Baseline BMI did not independently influence follow-up exercise hemodynamics, but weight gain across exams (the effect of 1 kg/m2 increase in BMI) was associated with higher exercise SBP and higher exercise HR. New-onset DM was associated with ~6 mm Hg higher exercise SBP, independent of weight gain, compared to those who remained free of DM across exams. Conclusions: CVD risk factors and their worsening over time were associated with higher exercise SBP and HR on follow-up. Our findings suggest that maintaining an optimal risk factor profile over the lifecourse will favorably impact exercise hemodynamic responsesover time.