Systolic blood pressure, diabetes and the risk of cardiovascular diseases in the Asia–Pacific region

Objective To assess the association between systolic blood pressure (SBP) and cardiovascular diseases (CVD) among participants with and without diabetes from cohorts in the Asia–Pacific region. Research design and methods Hazards ratios and 95% confidence intervals (CI) for CVD were calculated from Cox models, stratified by sex and region and adjusted for age using individual participant data from 36 cohort studies. Repeat measurements of SBP were used to adjust for regression dilution bias. Results During follow-up, 7387 fatal or non-fatal cardiovascular endpoints were recorded among 368 307 participants (6.4% with diabetes). SBP was associated with coronary heart disease (CHD), ischaemic stroke and haemorrhagic stroke in a continuous log-linear fashion among individuals with diabetes, as well as those without diabetes. Overall, each 10 mmHg higher usual SBP was associated with 18% (95% CI: 9–27%) and 23% (19–26%) greater risk for CHD among those with and without diabetes, respectively. The corresponding values for ischaemic stroke were 29% (14–45%) and 43% (37–50%), and for haemorrhagic stroke, 56% (32–83%) and 74% (66–82%). The test for heterogeneity by diabetes status in each of these associations was not significant (P ≥ 0.10). Conclusions Systolic blood pressure is an important marker of risk of CVD in people with and without diabetes. A given reduction in systolic blood pressure is likely to have a similar relative effect on reducing the risk of a cardiovascular event, regardless of diabetes status.