Independent and Joint Associations of Exercise Blood Pressure and Cardiorespiratory Fitness With the Risk of Cardiovascular Mortality

Background: We tested the hypothesis that an exaggerated systolic blood pressure (ESBP) at maximal exercise workload would be associated with an increased risk of cardiovascular disease (CVD) mortality, and that high cardiorespiratory fitness (CRF) attenuates this risk. Methods: This prospective study was based on the general population sample of 1,481 men (aged 42-61 years) who did not have a history of CVD at baseline and were followed up in the Kuopio Ischemic Heart Disease cohort study. Exercise blood pressure and CRF were measured during cardiopulmonary exercise testing, and an ESBP was defined by a peak systolic blood pressure ≥210 mm Hg and CRF categorized as tertiles and unfit and fit groups. Results: During a 26-year median follow-up, 231 CVD deaths occurred. After adjusting for potential confounding factors, an ESBP was associated with an increased risk of CVD mortality (hazard ratio [HR] 1.43, 95% confidence interval: 1.06-1.94), while the highest tertile of CRF was associated with a lower risk of CVD mortality (HR 0.64, 0.43-0.95). In the joint association analyses of ESBP and CRF, ≥210 mm Hg-unfit group had a higher risk of CVD mortality (HR 1.70, 1.02-2.83), but also ≥210 mm Hg-fit group had an increased risk of CVD death (HR 1.95, 1.20-3.18) compared with their <210 mm Hg-fit counterparts. Conclusions: These results indicate that an ESBP is independently associated with an increased risk of CVD death, but moderate-to-high levels of CRF does not attenuate CVD mortality risk in those with ESBP.