Abstract 3959: Exercise Blood Pressure and Long Term Mortality in a Population of Subjects without Known Cardiovascular Disease
Blood pressure is routinely measured during exercise testing, but data on its prognostic significance are limited. The present study asked whether maximum systolic blood pressure (MSBP) predicts long term all-cause mortality in subjects without known cardiovascular disease. We studied consecutive subjects referred for exercise testing from 1986–1991, excluding patients with known cardiovascular disease or risk equivalent (such as diabetes mellitus). All subjects underwent a symptom-limited treadmill test. All cause mortality was determined by the National Death Index through the end of August 2005. Cox proportional hazards regression was used to test the relationship between MSBP and all-cause mortality. MSBP was categorized in five groups using the group with the lowest mortality rate as referent (separately identified for men and women). Hazard ratios (HR) for the other groups were calculated in an unadjusted model (Model 1), with adjustment for age (Model 2), and with adjustment for age and exercise capacity (Model 3). During the study period, 7991 subjects (5914 men and 2077 women) were tested. In 16.4 ± 2.7 years of follow-up, deaths occurred in 465 men (7.9%) and 128 women (6.2%). In Model 1, risk of death increased significantly in groups with lower and the higher MSBP values compared to the referent (U-shape curve). In Model 2, and even more so in Model 3, the curves of risk flattened, so there was no longer an independent risk of mortality in men or women and at any level of MSBP (Figure⇓). These results suggest that maximum systolic blood pressure makes a limited contribution to prediction of all cause mortality in men and women without known cardiovascular disease.