Reverse J-curve relation between diastolic blood pressure and severity of coronary artery lesion in hypertensive patients with angina pectoris.

Abstract

The existence of the J-curve in hypertension treatment remains controversial. The major question is whether the increase in mortality from coronary disease is induced by the lowering of blood pressure (BP) or by the severity of underlying coronary artery disease. We recruited patients with a history of hypertension (systolic BP (SBP) >160 mmHg and/or diastolic BP (DBP) >90 mmHg) and a diagnosis of angina pectoris with angiographically confirmed coronary artery lesion. The relationship among the treated levels of SBP and DBP, the severity of coronary artery lesion, and the clinical consequences were investigated. Among the 234 enrolled patients, 115 experienced further events, 19 of which were serious. There were no significant differences in the average BP of patients with and those without events, but the coronary severity indices (CSI) were significantly greater in patients with events. As a function of DBP from < or = 74 to 105 < or = mmHg, there was a positive association with the incidence of serious events, and a reversed J-curve in CSI with a nadir at 95-104 mmHg. A similar relationship was observed in SBP, but a potentially unfavorable outcome was suggested in the lowest SBP range of < or = 124 mmHg. In conclusion, there was no J-curve for DBP in hypertensive patients with angina pectoris; rather, the lower the DBP, the better was the prognosis. Interestingly, the severity of coronary lesion is in a reversed J-curve relation with DBP, suggesting that high BP plays a critical role in serious events in hypertensive patients with moderate coronary artery lesions.