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Published on: September 16, 2017
IoT-Based Home Blood Pressure Time in Target Range and Brain Lesions on MRI
Takashi Hisamatsu1, Mari Fukuda1, Minako Kinuta1,2
1Department of Public Health, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Japan (T.H., M.F., M.K., N.N., H.K.).
Insights
Higher time in target range (TTR) for home blood pressure (BP) is linked to fewer brain lesions. This finding highlights TTR
Area of Science:
- Cardiovascular Research
- Neurology
- Medical Technology
Background:
- Time in Target Range (TTR) quantifies blood pressure (BP) control within recommended levels.
- Distribution and clinical significance of home BP TTR, especially concerning subclinical cerebrovascular disease, remain under-explored in community settings.
Purpose of the Study:
- To evaluate annual and seasonal TTR using Internet of Things (IoT)-based home BP monitoring.
- To investigate the association between home BP TTR and subclinical cerebrovascular disease detected via MRI in a community-based cohort.
Main Methods:
- Home BP was monitored twice daily, with weekly means derived from at least three daily readings.
- TTR was calculated as the percentage of weeks meeting specific BP targets (<135/85 mmHg for untreated, <125/75 mmHg for treated individuals).
- Brain lesions (lacunar infarcts, white matter hyperintensities, microbleeds, intracranial stenosis) were assessed using MRI.
Main Results:
- Median annual TTR was 100% for untreated and 1.9% for treated participants.
- TTR was generally lower in winter compared to summer.
- Higher TTR correlated with a reduced prevalence of brain lesions (PR per 10% increase: 0.85; 95% CI, 0.79-0.91), with a stronger association in untreated individuals.
Conclusions:
- Home BP TTR offers valuable insights into long-term BP management.
- TTR assessment can provide complementary information for evaluating cerebrovascular health.
Background:
Time in target range (TTR) reflects the proportion of time that blood pressure (BP) stays within guideline-recommended levels. However, the distribution of home BP TTR and its association with subclinical cerebrovascular disease in community-based populations remain unclear.
Methods:
We investigated annual and seasonal TTR of Internet of Things-based home BP and its association with brain lesions on magnetic resonance imaging in a community-based cohort. Home BP was measured twice daily (morning and evening). Weekly mean BP was calculated from ≥3 valid daily readings, and TTR was defined in those with ≥2 valid weeks/season as the percentage of weeks meeting guideline-based targets (systolic and diastolic BP <135 and <85 mm Hg, respectively, for participants not receiving antihypertensive medication; <125 and <75 mm Hg, respectively, for those receiving medication). Brain lesions included ≥1 magnetic resonance imaging-detected lacunar infarct, white matter hyperintensities, cerebral microbleeds, or intracranial artery stenosis.
Results:
Among 306 participants (mean age, 56 years; 57% women), median annual TTR was 100% (interquartile range, 92.6%-100%) in participants not receiving antihypertensive medication and 1.9% (0%-19.2%) in those receiving medication. TTR tended to be lower in winter than in summer. In Poisson regression with robust variance, adjusted for demographic, lifestyle, and clinical factors, higher TTR was associated with a lower prevalence of brain lesions (prevalence ratio per 10% higher, 0.85 [95% CI, 0.79-0.91]). The association was stronger among participants not receiving antihypertensive medication (interaction P=0.047), with no heterogeneity across seasons (interaction P=0.958).
Conclusions:
Home BP TTR may help characterize longitudinal BP control and provide complementary information regarding cerebrovascular health.
