Safety and Efficacy of Low Blood Pressures Among Patients With Diabetes Subgroup Analyses From the ONTARGET (ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial)

OBJECTIVES: We sought to determine whether the blood pressure (BP) levels at which cardiovascular (CV) protection is achieved differ between diabetic and nondiabetic patients from the ONTARGET (ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial). BACKGROUND: Greater absolute benefits of BP reductions have been claimed for diabetic as compared with nondiabetic patients. METHODS: A total of 25,584 patients (9,603 diabetic), older than 55 years, at high CV risk were randomized to ramipril, telmisartan, or both and observed for 4.6 years. We pooled the treatment arms to examine the relationships between BP and the primary composite outcome (CV death, nonfatal myocardial infarction or stroke, or hospitalized heart failure) and its components. RESULTS: The primary outcome occurred in 1,938 (20.2%) diabetic patients and in 2,276 (14.2%) nondiabetic patients. Compared with nondiabetic patients, diabetic patients had a significantly higher risk for the primary endpoint (hazard ratio [HR]: 1.48; 95% confidence interval [CI]: 1.38 to 1.57) and CV death (HR: 1.56; 95% CI: 1.42 to 1.71); myocardial infarction (HR: 1.30 (95% CI: 1.17 to 1.46); stroke (HR: 1.39; 95% CI: 1.23 to 1.56); and congestive heart failure hospitalization (HR: 2.06; 95% CI: 1.82 to 2.32). The CV risk was significantly higher in diabetic than in nondiabetic patients regardless of the systolic BP changes during treatment. In both diabetic and nondiabetic patients, progressively greater systolic BP reductions were accompanied by reduced risk for the primary outcome only if baseline systolic BP levels ranged from 143 to 155 mm Hg; except for stroke, there was no benefit in fatal or nonfatal CV outcomes by reducing systolic BP below 130 mm Hg. CONCLUSIONS: The relationship between BP and overall CV risk had a similar pattern in diabetic and nondiabetic patients over a wide range of baseline and in-treatment BP values although, for the same systolic BP, a higher risk is observed in diabetic patients.