Cardiovascular outcomes under hypothetical blood‐pressure‐lowering intervention in type 2 diabetes: A target trial emulation

AIMS: The effective target for systolic blood pressure (SBP) control in patients with diabetes was inconsistent. We evaluated the emulated effect of maintaining SBP below clinical thresholds on the risk of cardiovascular disease (CVD) and all-cause mortality. MATERIALS AND METHODS: This study included 4264 patients with type 2 diabetes from the Kailaun study. We implemented the parametric g-formula to simulate the hypothetical interventions on reducing SBP below 140, 130 and 120 mmHg over time, accounting for time-varying confounding, reporting risk ratio (RR) and number needed to treat (NNT) for 10-year risk of CVD and all-cause mortality. RESULTS: Maintaining SBP below 140, 130 and 120 mmHg was associated with an 18%, 24%, and 31% relative risk reduction in the risk of CVD, with the RR (95% confidence interval [CI]) of 0.82 (0.75-0.88), 0.76 (0.69-0.86), and 0.69 (0.58-0.84), and the NNT of 32, 24, and 19, respectively, compared to no intervention. However, the benefits in reducing the risk of all-cause mortality did not reach a significant level with maintaining SBP below 140 and 130 mmHg, with the RR (95% CI) of 0.98 (0.93-1.06) and 1.04 (0.95-1.12), respectively. The risk of all-cause mortality significantly increased 15% with maintaining SBP ≤120 mmHg (RR, 1.15; 95% CI, 1.02-1.32). Subgroup analyses showed that maintaining SBP ≤120 mmHg tended to bring more harms than benefits in patients aged ≥60 years or without antihypertensive agents. CONCLUSION: Among Chinese patients with type 2 diabetes, maintaining SBP ≤120 mmHg may not be an optimal target, in terms of the risk-benefit association of CVD and all-cause mortality.