Audio summary using Dr. Kar’s AI-cloned voice
When we think about blood pressure, we tend to think in snapshots: one reading in the clinic, one reading at home, one reading before a procedure. But optimal blood pressure isn’t about measuring it once in a while. What may matter as much as the actual numbers is how many weeks and months a person’s blood pressure stays within a healthy range, called Blood Pressure Time in Target Range (BP-TTR) (Wang et al., 2025).
Rather than simply asking whether blood pressure is high or normal at a given moment, the concept of time in target range poses a more nuanced question: how long does blood pressure remain within a healthy range over a defined period? The distinction mirrors the difference between a screenshot and a video. A screenshot captures information at a single, fixed point in time, whereas a video reveals a far richer and more dynamic picture of what is happening.
Two people may share identical average blood pressure readings yet have vastly different levels of risk for heart disease and stroke, depending on how their pressure behaves throughout the day and night. One person may remain close to the target range most of the time, while another experiences repeated swings above it, producing the same numerical average but a substantially greater disease burden (Wang et al., 2025; Li et al., 2024).
What is Blood Pressure Time in Target Range?
Blood pressure time at target, or time in target range, means the proportion of time when a person’s BP is within a chosen goal, such as below 120/80 mmHg or within a systolic range like 120–140 mmHg. The idea is that two people can have the same average BP, but the one whose BP remains more consistently controlled may have better outcomes.
Why is Blood Pressure Time in Target Range Important?
Multiple studies have shown the benefits of a higher percentage of time spent in the target or therapeutic range of blood pressure, leading to lower risk of heart disease, stroke and death from all causes.
In a 2017 study, more than 68,000 veterans were followed for 10 years. Patients with systolic blood pressure levels within the range of 120–140 mm Hg had significantly lower death rates than patients with blood pressure levels above or below this range, while the time in therapeutic range was a strong survival predictor: patients with consistent (>50%) compared with patients with inconsistent (<50%) blood pressure values within this range had 2‐ to 3‐fold lower death rates. ( Doumas et al., 2017).
The strongest body of evidence on time in target range for blood pressure comes from two major research reviews, each of which pooled findings from dozens of published studies and examined years of blood pressure data from thousands of patients across multiple countries. Despite differences in how individual studies defined and measured time in the target range, the conclusions consistently pointed in the same direction: the more time spent within a healthy blood pressure range, the better the outcomes (Li et al., 2024; Wang et al., 2025).
Knowing your average blood pressure is useful, but it does not tell the whole story. A normal reading at one point in time is reassuring, but it is still just a snapshot. In several studies, people whose average or most recent reading looked acceptable were still found to carry elevated heart disease, stroke, and dementia risk when blood pressure time-in-target range was examined.
Is there a definition of blood pressure time-in- target range?
There is no single universal definition of blood pressure time-in-target range. Across the literature, it has been calculated in different ways using home blood pressure monitoring, 24-hour ambulatory monitoring, and repeated clinic measurements collected over months or years, with each study setting its own target range and minimum data requirements. Some studies use simple proportions of readings in range, while others use interpolation-based methods to estimate time spent within the target over longer periods.
How a Continuous Wrist Monitor Defined Blood Pressure Time-in-Target Range
A large-scale study used a continuous, clinically validated cuffless wrist monitor, the Hilo device, to investigate how reliably blood pressure time-in-target range can be measured under everyday conditions. Its purpose was to determine how many days of continuous monitoring are needed to accurately classify blood pressure time-in-target range and to establish a working definition of the metric for this type of device.
The study analyzed 2.25 million blood pressure readings from 5,189 European home users with a mean age of 55.3 years. Blood pressure time in target range was defined as the proportion of systolic BP readings within the target range of 90–125 mmHg over a 15-day reference period; days included in the analysis required at least six daytime readings. Seven consecutive days of continuous 24-hour monitoring were sufficient to achieve 90% sensitivity for time-in-target-range classification, whereas shorter monitoring periods were unreliable. (Fisher et al., 2024).
Bottom line: Regardless of the method used, the longer blood pressure remains at the treatment target zone, the better the health outcome.
What Does This Mean for You?
Start with home blood pressure monitoring. Out-of-the-doctor ‘s-office blood pressure readings are recommended by most hypertension guidelines. It is more informative than a single clinic reading. Use an accurate home BP device. An average of 3 readings morning, afternoon and evening, taken over several days, builds a picture no single clinic visit can provide. Track your blood pressure using this sheet.
Consider 24-hour ambulatory blood pressure monitoring. This captures patterns that home monitoring misses entirely, including nighttime blood pressure and early-morning blood pressure. It remains one of the most informative tests available.
Explore continuous cuffless monitoring. The Hilo wrist device generates approximately 29 readings per day, including during sleep (Fisher et al., 2024). Research has shown that seven consecutive days of monitoring are sufficient to classify blood pressure time in the target range with 90% or greater accuracy. Readings can be shared directly with a healthcare provider.
Treat blood pressure as a pattern, not a single number. The more time spent in a healthy blood pressure range, the better the outcome for heart disease, stroke, and dementia risk. The question to ask is not “was my BP reading normal today?” but “how consistently is my blood pressure staying in range?”
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References
- Doumas, Michael, et al. “Time in therapeutic range, as a determinant of all‐cause mortality in patients with hypertension.” Journal of the American Heart Association 6.11 (2017): e007131.
- Wang, Huairong, et al. “Time in target range for blood pressure and adverse health outcomes: a systematic review.” Hypertension 82.3 (2025): 419-431.
- Li, W., Gnanenthiran, S. R., Schutte, A. E., et al. (2024). Blood pressure time at target and its prognostic value for cardiovascular outcomes: A scoping review. Hypertension Research, 47, 2337–2350. https://doi.org/10.1038/s41440-024-01798-1
- Fisher, N. D. L., Almeida, T. P., Perruchoud, D., Shah, J., & Sola, J. (2024). Optimizing time-in-target-range assessment for blood pressure: Insights from a large-scale study with continual cuffless monitoring. Frontiers in Medicine, 11, Article 1396962. https://doi.org/10.3389/fmed.2024.1396962
