Time in Target Range for Blood Pressure and Adverse Health Outcomes: A Systematic Review

Blood pressure (BP) time in target range (TTR) reflects the proportion of time that BP measurement is within a specified target range. We aim to summarize the evidence for relationships between TTR and adverse health outcomes.

Seven databases were searched. After quality assessment and data extraction, meta-analyses were performed to generate pooled estimates of the association (hazard ratios) between TTR and health outcomes. Primary outcomes were all-cause mortality and cardiovascular death. Secondary outcomes included major adverse cardiovascular events, myocardial infarction, stroke, heart failure, atrial fibrillation, and adverse kidney events.

In all, 21 studies were included, mostly rated at low risk of bias. TTR was defined by systolic BP (SBP) in 15 studies and by both SBP and diastolic BP in 6 studies. Per SD increase of TTR was associated with significantly decreased risks of all-cause mortality (110-130 mm Hg SBP TTR: hazard ratios, 0.85 [95% CI, 0.82-0.89]; 120-140 mm Hg SBP TTR: 0.81 [95% CI, 0.70-0.94]; and 70-80 mm Hg diastolic BP TTR: 0.88 [95% CI, 0.83-0.93]), cardiovascular death (110-130 mm Hg SBP TTR: 0.83 [95% CI, 0.78-0.87]; 120-140 mm Hg SBP TTR: 0.76 [95% CI, 0.65-0.89]; and 70-80 mm Hg diastolic BP TTR: 0.85 [95% CI, 0.80-0.90]), major adverse cardiovascular events (120-140 mm Hg SBP TTR: 0.76 [95% CI, 0.70-0.83]), and heart failure (110-130 mm Hg SBP TTR: 0.84 [95% CI, 0.76-0.93] and 120-140 mm Hg SBP TTR: 0.78 [95% CI, 0.68-0.89]). However, there was not sufficient support for the association of TTR with myocardial infarction, stroke, atrial fibrillation, or adverse kidney events.

Higher TTR was associated with reduced risks of all-cause mortality, cardiovascular death, major adverse cardiovascular events, and heart failure, highlighting the importance of sustained BP control in clinical practice.

URL: https://www.crd.york.ac.uk/PROSPERO/; Unique identifier: CRD42023486437.