Blood Pressure During Submaximal Exercise As A Predictor Of Future Hypertension In Normotensive Men

Abstract

PURPOSE: Although the maximal exercise blood pressure (BP) response has been associated with incident hypertension, whether the initial BP response during exercise testing is associated with the incidence of hypertension in normotensive men is unclear. We examined the hypothesis that the systolic BP (SBP) response during stage 1 of standard exercise testing is associated with the incidence of hypertension in normotensive men. Furthermore, we investigated whether these associations persisted after adjusting for maximal BP. METHODS: Subjects were 3417 men (mean age 48±6yrs) who participated in 2 health examinations during 1998-2009. All subjects were free of cardiovascular diseases, diabetes, and hypertension at baseline. Exercise BP was measured during the last min of each progressive stage and at peak effort using an automatic BP monitor. The absolute exercise BP at stage 1 and the relative (changes in) exercise BP (BP at stage 1 minus resting BP) were calculated as potential indices of incident hypertension. Incident hypertension was defined as SBP and diastolic BP (DBP) ≥ 140/90mmHg and/or hypertension diagnosed by a physician at the 2nd examination. RESULTS: During an average follow-up of 5 years, 340 (10%) subjects developed hypertension. Subjects within the highest quartile of absolute SBP (>146mmHg) and DBP (>85mmHg) had 3.78-fold (95% CI, 2.30-6.22) and 3.89-fold (95% CI, 2.59-5.85) risks of developing hypertension as compared to subjects in the respective lowest quartiles after adjusting for confounders. In addition, subjects within the highest quartile of SBP (>28mmHg) and DBP (>10mmHg) change had 2.30-fold (95% CI, 1.61-3.29) and 1.64-fold (95% CI, 1.20-2.25) risks of developing hypertension as compared to subjects with the lowest quartile of SBP (<11mmHg) and DBP (<-3mmHg) change after adjusting for potential confounders, including maximal SBP. Interestingly, stage 1 SBP (AUC=0.693, 95% CI, 0.664-0.721) was a better predictor of incident hypertension than maximal SBP (AUC=0.643, 95% CI, 0.613-0.673). CONCLUSIONS: Assessment of the BP response during the initial stage of exercise testing may serve as a useful new prognostic marker for future hypertension, complementing or even replacing the maximal BP.