The current American, European, and Japanese guidelines for hypertension treatment have lowered blood pressure (BP) targets to <130/80 mmHg in patients with diabetes mellitus (DM) and patients with coronary artery disease (CAD). However, there is concern that low BP may increase cardiovascular events in diabetic CAD patients. Currently, coronary revascularization has become widespread in diabetic CAD patients. Thus, whether low BP is an independent risk factor for cardiovascular events in diabetic CAD patients after revascularization was investigated. We examined 2718 stable CAD patients with DM in the CREDO-Kyoto cohort-1 registry enrolling 9877 patients who underwent their first percutaneous coronary intervention or coronary bypass grafting. There were no cutoff points for systolic BP (SBP) below which the age- and sex-adjusted hazard ratios for cardiovascular death, nonfatal myocardial infarction (MI), and nonfatal stroke increased. The cutoff diastolic BP (DBP) for increasing cardiovascular death was 70 mmHg (P = 0.014), whereas there was no cutoff DBP for increasing nonfatal MI and nonfatal stroke. However, on stepwise Cox hazard proportional regression analysis, the independent factors increasing cardiovascular death were hypertension, low creatinine clearance, wide pulse pressure, prior MI, and nonuse of statins, but DBP < 70 mmHg was not a significant factor. In conclusion, in diabetic CAD patients after coronary revascularization, low SBP and DBP were not significant factors that increased cardiovascular events. Careful attention should be paid to vascular lesions and organ damage that have already progressed.
Keywords: Blood pressure; Cardiovascular events; Coronary artery disease; Diabetes mellitus; J-curve phenomenon.