Real-World Systolic and Diastolic Blood Pressure Levels and Cardiovascular Mortality in Patients with Type 2 Diabetes - Results from a Large Registry Cohort in Asia.

Background Elevated blood pressure (BP) is associated with increased risk of cardiovascular mortality. However, there is ongoing debate whether intensive BP lowering may paradoxically increase the risk of cardiovascular disease (CVD) especially in patients with type 2 diabetes mellitus (T2DM). We investigated the association of BP with risk of CVD mortality in patients with T2DM. Methods and Results We used data on 83,721 patients with T2DM from a multi-institutional diabetes registry in Singapore from 2013 to 2019. BP was analyzed as categories and restricted cubic splines using cox multivariable regression analysis stratified by pre-existing CVD and age (< 65 years vs ≥ 65 years). The primary outcome was CVD mortality, determined via linkage with national registry. Among 83,721 patients with T2DM (mean age 65.3 years, 50.6% women, 78.9% on antihypertensive medications), 7.6 per 1000 person-years experienced the primary outcome. SBP had a graded relationship with a significant increase in CVD mortality at levels higher than 120-129 mm Hg. DBP levels above 90 mm Hg were significantly associated with CVD mortality in those aged ≥ 65 years. In addition, DBP less than 70 mm Hg was associated with a significantly higher risk of CVD mortality in all patients. Conclusions In patients with T2DM, clinic SBP levels ≥130 mm Hg or DBP levels ≥ 90 mm Hg are associated with higher risk of CVD mortality. DBP < 70 mm Hg is also associated with risk of adverse CVD outcomes although reverse causality cannot be ruled out.