Abstract 13496: Exercise Blood Pressure as a Predictor of Future Hypertension: Evaluation Using Receiver Operating Characteristic
The meaningful cutoff values for exaggerated blood pressure (EBP) response to exercise are inconsistent and arbitrarily defined, and confounding variables in the association between EBP and future hypertension are often not adequately accounted for. The purpose of this study is 1) to evaluate receiver operating characteristic curve to identify optimal cutoffs of EBP using both a maximal systolic blood pressure (SBP) and a relative SBP as predictors of future hypertension, and 2) to analyze the validity of 210 mmHg of the EBP cutoff value suggested in previous studies for men. Study participants were 3,742 men who participated in two health examinations during 1998-2009. All the participants were free of cardiovascular diseases and hypertension at baseline examination. The relative SBP were calculated as the difference between the resting SBP before and the maximal SBP during exercise testing. Hypertension was defined as systolic or diastolic blood pressure ≥140/90mmHg. During 5 years of follow-up, 364 (9.7%) new cases of hypertension developed. Individuals with exercise SBP >210 mmHg had a 1.67 times [95% confidence interval (CI) 1.19-2.35] increased risk of incident hypertension, but this association was not significant in the multivariable-adjusted model (RR 1.04, 95% CI 0.73-1.48). The best cutoff points of the maximal SBP and relative SBP for predicting the incidence of hypertension were 181mmHg (AUC=0.644, sensitivity=54% and specificity=69%) and 52mmHg (AUC=0.549, sensitivity=64.3% and specificity=44.6%), respectively. Subjects with maximal SBP (>181mmHg) and relative SBP (>52mmHg) had a 1.54-fold (95% CI, 1.23-1.93) and a 1.44-fold (95% CI, 1.16-1.80) risks of developing hypertension. When these two variables were entered simultaneously into the Cox proportional hazards regression model with adjustment for confounding factors, only maximal SBP (RR 1.39, 95% CI 1.02-1.89) was a predictor of the development of hypertension. These results demonstrate that both maximal and relative SBP responses to exercise were associated with the incidence of hypertension, but a maximal SBP with cutoff point of >181mmHg is a better predictor of future hypertension than a relative SBP independent of confounding variables in normotensive men.
Author Disclosures: S. Jae: None. M. Carnethon: None. J. Choo: None. Y. Choi: None. B. Fernhall: None.
- © 2014 by American Heart Association, Inc.