Systolic blood pressure time in target range and cardiovascular disease and premature death

Abstract Background Time-in-target range (TTR) for systolic blood pressure (SBP) independently predicts cardiovascular outcomes. However, there are limited research based on real-world data. Purpose To estimate SBP-TTR associated with cardiovascular disease (CVD) and premature death among the employed individuals with hypertension. Methods This study is based on the Kailuan cohort. As part of the Kailuan study, a workplace-based hypertension management programme was initiated in 2009 for employed people with hypertension. The TTR was defined as 120 to 140 mmHg according to the current guidelines, and in the sensitivity analyses it was further defined as 110 to 130 mmHg. TTR was estimated over the first 6 months of follow-up using linear interpolation. The association between SBP-TTR with CVD, premature CVD and premature death was estimated using adjusted Cox proportional hazards regression models to adjust for multiple confounders. Results A total of 9552 hypertensive participants were included. A one standard deviation increase in SBP-TTR is associated with a 19% reduction in the risk of CVD (HR:0.81; 95%CI: 0.74 to 0.88), a 24% reduction in the risk of premature CVD (HR:0.76; 95%CI: 0.67 to 0.86), and a 17% reduction in the risk of premature death (HR:0.83; 95%CI: 0.74 to 0.92). When SBP-TTR is redefined as 110-130 mmHg, a one standard deviation increase in SBP-TTR is associated with a 23% reduction in the risk of CVD (HR:0.77; 95%CI: 0.70 to 0.84), a 30% reduction in the risk of premature CVD (HR:0.70; 95%CI: 0.60 to 0.81), and a 27% reduction in the risk of premature death (HR:0.73; 95%CI: 0.66 to 0.80). These associations were independent of SBP-mean and SBP-SD. Subgroup analysis results indicate that SBP-TTR contributes to a reduction in the risk of premature death in individuals with a high cardiovascular risk score. Conclusions SBP-TTR was statistically associated with a decreased risk of CVD, premature CVD and premature death. Intensifying blood pressure control measures can further increase cardiovascular benefits.