Changes in Home Blood Pressure Monitored Among Elderly Patients With Hypertension During the COVID-19 Outbreak: A Longitudinal Study in China Leveraging a Smartphone-Based Application

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has impacted clinical care worldwide. Evidence of how this health crisis affected common conditions like blood pressure (BP) control is uncertain. METHODS: We used longitudinal BP data from an ongoing randomized clinical trial to examine variations in home BP monitored via a smartphone-based application (app) in a total of 7394 elderly patients with hypertension aged 60 to 80 years stratified by their location in Wuhan (n=283) compared with other provinces of China (n=7111). Change in morning systolic BP (SBP) was analyzed for 5 30-day phases during the pandemic, including preepidemic (October 21 to November 20, 2019), incubation (November 21 to December 20, 2019), developing (December 21, 2019 to January 20, 2020), outbreak (January 21 to February 20, 2020), and plateau (February 21 to March 21, 2020). RESULTS: Compared with non-Wuhan areas of China, average morning SBP (adjusted for age, sex, body mass index) in Wuhan patients was significantly higher during the epidemic growth phases, which returned to normal at the plateau. Between-group differences in ΔSBP were +2.5, +3.0, and +2.1 mm Hg at the incubation, developing, and outbreak phases of COVID-19 (P<0.001), respectively. Sensitivity analysis showed a similar trend in trajectory pattern of SBP in both the intensive and standard BP control groups of the trial. Patients in Wuhan also had an increased regimen change in antihypertensive drugs during the outbreak compared with non-Wuhan patients. Expectedly, Wuhan patients were more likely to check their BP via the app, while doctors were less likely to monitor the app for BP control during the pandemic. CONCLUSIONS: Our data demonstrate that the COVID-19 pandemic was associated with a short-term increase in morning SBP among elderly patients with hypertension in Wuhan but not other parts of China. Further study will be needed to understand if these findings extended to other parts of the world substantially affected by the virus. REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03015311.