Background
Blood pressure (BP) is a continuous and dynamic measure. However, standard BP control metrics may not reflect the variability in BP over time.

Objectives
This study assessed the prognostic value of time in BP target range among hypertensive patients with heart failure (HF).

Methods
The authors performed a post hoc analysis of data from the TOPCAT (Treatment of Preserved Cardiac Function HF with an Aldosterone Antagonist) trial and the BEST (Beta-Blocker Evaluation of Survival Trial). Time in target range (TTR) for each patient was calculated using linear interpolation across the study period with the target range of systolic BP between 120 and 130 mm Hg.

Results
A total of 4,789 hypertensive patients (n = 1,654 from BEST and n = 3,135 from TOPCAT) were included. The cumulative incidences of primary endpoint (ie, cardiovascular death or HF hospitalization) were highest among the top quartile of TTR with a dose-dependent manner across quartiles (Ptrend <0.005). The top quartile of TTR was significantly associated with a lower risk of primary outcome using adjusted Cox regression model (HR: 0.71; 95% CI: 0.60-0.82), cardiovascular mortality (HR: 0.68; 95% CI: 0.55-0.84), HF hospitalization (HR: 0.70; 95% CI: 0.58-0.85), all-cause mortality (HR: 0.69; 95% CI: 0.58-0.83), and any hospitalization (HR: 0.76; 95% CI: 0.67-0.85). Further analyses using restricted cubic spline indicated a linear relationship between TTR and primary outcome. Similar patterns were observed in the individual trial. Sensitivity analyses generated consistent results while redefining target range as 110 to 130 mm Hg for systolic BP or 70 to 80 mm Hg for diastolic BP.

Conclusions
TTR could independently predict major adverse cardiovascular events in hypertensive patients with HF.