Abstract 15019: Graded Relationships Between Blood Pressure Levels and Cardiovascular Mortality in Patients With Type 2 Diabetes: Results From a Large Registry Cohort in Asia

Abstract

Introduction: Elevated 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) in patients with type 2 diabetes mellitus (T2DM). This study was undertaken to understand the association of BP with risk of CVD mortality in patients with T2DM. Method: This was a cohort study on 83,721 patients with T2DM age 40 years or older using data from a multi-institutional diabetes registry in Singapore from 2013 to 2019. The relationships between BP and CVD mortality were analyzed using Cox multivariable regression model, adjusting for covariates including gender, use of anti-hypertensive medications and presence of co-existing CVD. Results: Overall, the mean age was 65.3 years with 50.6% women, 78.9% on antihypertensive medications, 21.3% with pre-existing CVD and 7.6 per 1000 person-years experienced the outcome over 7 years. Compared to SBP 120-129 mm Hg, the risk of CVD mortality was higher in SBP 140 mm Hg in patients with and without pre-existing CVD, the elderly and non-elderly. The hazard ratios (HR) were 1.27 (95% CI: 1.12-1.45), 1.87 (1.65-2.12), 1.49 (1.35-1.64) and 1.87 (1.55-2.25), respectively. Using DBP 70-79 mm Hg as reference, DBP < 70 mm Hg was also associated with higher risk of CVD mortality in all patient groups, with corresponding HR 1.25 (1.12-1.39), 1.23 (1.11-1.36), 1.19 (1.10-1.29) and 1.54 (1.32-1.80), respectively. DBP 90 mm Hg was also associated with higher risk of CVD mortality in the elderly and those without pre-existing CVD. Conclusion: In patients with T2DM, higher SBP is associated with raised CVD mortality risk. Elevated DBP is independently associated with higher risk of CVD mortality albeit only in those without pre-existing CVD and the elderly. DBP < 70 mm Hg is also associated with risk of CVD outcome although reverse causality cannot be ruled out.