Objectives: Estimate risks of coronary heart disease (CHD), stroke and cardiovascular disease (CVD) with updated mean systolic (SBP) and diastolic (DBP) blood pressure in an observational study of patients with type 2 diabetes.
Methods: Thirty-five thousand and forty-one patients treated with antihypertensive drugs, and 18 512 untreated patients, aged 30-75 years, without previous heart failure, followed for 6 years until 2009.
Results: In treated patients, nonlinear splines for 6-year risk of fatal/nonfatal CHD, stroke and CVD by BP as a continuous variable showed a progressive increase with higher SBP from 140 mmHg and higher, and with DBP from 80 mmHg, with a J-shaped risk curve at lowest SBP levels, but not obviously at lowest DBP levels. Analysing intervals of SBP with 130-134 mmHg as reference at Cox regression, adjusted hazard ratios (HR) for fatal/nonfatal CHD, stroke and CVD with at least 140 mmHg were 1.22 [95% confidence interval (CI): 1.08-1.39], 1.43 (1.18-1.72), 1.26 (1.13-1.41), all P < 0.001. HR with 115-129 and 135-139 mmHg were nonsignificant, whereas increased with 100-114 mmHg, 1.96 (P < 0.001), 1.75 (P = 0.02), 2.08 (P < 0.001), respectively. With DBP 75-79 mmHg as reference, adjusted HR for fatal/nonfatal CHD, stroke and CVD with DBP 80-84 mmHg were 1.42 (1.26-1.59), 1.46 (1.24-1.72), 1.39 (1.26-1.53), all P < 0.001. Corresponding HR with DBP at least 85 mmHg were 1.70 (1.50-1.92), 2.35 (1.99-2.77), 1.87 (1.69-2.07), all P < 0.001. Corresponding HR with DBP 60-69 and 70-74 mmHg were nonsignificant. The picture was similar in 7059 patients with previous CVD and in untreated patients.
Conclusion: BP around 130-135/75-79 mmHg showed lower risks of cardiovascular diseases in patients with type 2 diabetes.