Department of Epidemiology and Biostatistics, Peking University, Beijing, China.
Key Laboratory of Epidemiology of Major Diseases (Peking University), Ministry of Education, Beijing, China.
J Med Internet Res. 2024 Aug 14;26:e50075. doi: 10.2196/50075.
The paucity of evidence on longitudinal and consecutive recordings of physical activity (PA) and blood pressure (BP) under real-life conditions and their relationships is a vital research gap that needs to be addressed.
This study aims to (1) investigate the short-term relationship between device-measured step volume and BP; (2) explore the joint effects of step volume and variability on BP; and (3) examine whether the association patterns between PA and BP varied across sex, hypertension status, and chronic condition status.
This study used PA data of a prospective cohort of 3070 community-dwelling older adults derived from a mobile health app. Daily step counts, as a proxy of step volume, were derived from wearable devices between 2018 and 2022 and categorized into tertiles (low, medium, and high). Step variability was assessed using the SD of daily step counts. Consecutive daily step count recordings within 0 to 6 days preceding each BP measurement were analyzed. Generalized estimation equation models were used to estimate the individual and joint associations of daily step volume and variability with BP. Stratified analyses by sex, the presence of hypertension, and the number of morbidities were further conducted.
A total of 3070 participants, with a median age of 72 (IQR 67-77) years and 71.37% (2191/3070) women, were included. Participants walked a median of 7580 (IQR 4972-10,653) steps and 5523 (IQR 3590-7820) meters per day for a total of 592,597 person-days of PA monitoring. Our results showed that higher levels of daily step volume were associated with lower BP (systolic BP, diastolic BP, mean arterial pressure, and pulse pressure). Compared with participants with low step volume (daily step counts <6000/d) and irregular steps, participants with high step volume (≥9500/d) and regular steps showed the strongest decrease in systolic BP (-1.69 mm Hg, 95% CI -2.2 to -1.18), while participants with medium step volume (6000/d to <9500/d) and regular steps were associated with the lowest diastolic BP (-1.067 mm Hg, 95% CI -1.379 to -0.755). Subgroup analyses indicated generally greater effects on women, individuals with normal BP, and those with only 1 chronic disease, but the effect pattern was varied and heterogeneous between participants with different characteristics.
Increased step volume demonstrated a substantial protective effect on BP among older adults with chronic conditions. Furthermore, the beneficial association between step volume and BP was enhanced by regular steps, suggesting potential synergistic protective effects of both increased step volume and step regularity. Targeting both step volume and variability through PA interventions may yield greater benefits in BP control, particularly among participants with hypertension and a higher chronic disease burden.
在真实生活条件下，关于体力活动（PA）和血压（BP）的纵向和连续记录及其关系的证据很少，这是一个亟待解决的重要研究空白。
本研究旨在：（1）研究设备测量的步幅量与 BP 的短期关系；（2）探讨步幅量和变异性对 BP 的联合影响；（3）检验 PA 与 BP 之间的关联模式是否因性别、高血压状态和慢性病状态而异。
本研究使用了来自移动健康应用程序的一项前瞻性队列研究的 3070 名社区居住的老年人的 PA 数据。日常步幅计数（代表步幅量）由可穿戴设备在 2018 年至 2022 年期间得出，并分为三分位（低、中、高）。步幅变异性使用每日步幅计数的标准差来评估。分析了在每次 BP 测量前 0 至 6 天内连续的每日步幅记录。使用广义估计方程模型来估计每日步幅量和变异性与 BP 的个体和联合关联。进一步进行了按性别、高血压存在和慢性病数量分层的分析。
共纳入 3070 名参与者，中位年龄为 72（IQR 67-77）岁，71.37%（2191/3070）为女性。参与者每天平均行走 7580（IQR 4972-10653）步和 5523（IQR 3590-7820）米，共计 592597 人天的 PA 监测。我们的结果表明，较高水平的日常步幅量与较低的 BP（收缩压、舒张压、平均动脉压和脉压）相关。与低步幅量（每日步数<6000/d）和不规则步幅的参与者相比，高步幅量（≥9500/d）和规则步幅的参与者收缩压下降幅度最大（-1.69mmHg，95%CI-2.2 至-1.18），而中步幅量（6000/d 至<9500/d）和规则步幅的参与者舒张压下降幅度最低（-1.067mmHg，95%CI-1.379 至-0.755）。亚组分析表明，对女性、血压正常的个体以及只有 1 种慢性病的个体通常有更大的影响，但在不同特征的参与者之间，效应模式存在差异且不均匀。
在患有慢性病的老年人中，增加步幅量对 BP 具有显著的保护作用。此外，步幅量和 BP 之间的有益关联通过规则的步幅得到增强，这表明增加步幅量和规则性都可能具有协同的保护作用。通过 PA 干预来针对步幅量和变异性可能会在 BP 控制方面带来更大的益处，特别是对高血压和慢性病负担较高的参与者。
