Scripps Research Translational Institute, La Jolla, California, United States of America.
University of Alberta, Division of Cardiology, Edmonton, Alberta, Canada.
PLoS One. 2020 Feb 5;15(2):e0227709. doi: 10.1371/journal.pone.0227709. eCollection 2020.
Heart rate is routinely measured as part of the clinical examination but is rarely acted upon unless it is well outside a population-based normal range. With wearable sensor technologies, heart rate can now be continuously measured, making it possible to accurately identify an individual's "normal" heart rate and potentially important variations in it over time. Our objective is to describe inter- and intra-individual variability in resting heart rate (RHR) collected over the course of two years using a wearable device, studying the variations of resting heart rate as a function of time of year, as well as individuals characteristics like age, sex, average sleep duration, and body mass index (BMI).
Our retrospective, longitudinal cohort study includes 92,457 de-identified individuals from the United States (all 50 states), who consistently-over at least 35 weeks in the period from March 2016 to February 2018, for at least 2 days per week, and at least 20 hours per day-wore a heart rate wrist-worn tracker. In this study, we report daily RHR and its association with age, BMI, sex, and sleep duration, and its variation over time. Individual daily RHR was available for a median of 320 days, providing nearly 33 million daily RHR values. We also explored the range in daily RHR variability between individuals, and the long- and short-term changes in the trajectory of an individual's daily RHR. Mean daily RHR was 65 beats per minute (bpm), with a range of 40 to 109 bpm among all individuals. The mean RHR differed significantly by age, sex, BMI, and average sleep duration. Time of year variations were also noted, with a minimum in July and maximum in January. For most subjects, RHR remained relatively stable over the short term, but 20% experienced at least 1 week in which their RHR fluctuated by 10 bpm or more.
Individuals have a daily RHR that is normal for them but can differ from another individual's normal by as much as 70 bpm. Within individuals, RHR was much more consistent over time, with a small but significant seasonal trend, and detectable discrete and infrequent episodes outside their norms.
心率通常作为临床检查的一部分进行测量，但除非超出基于人群的正常范围，否则很少采取行动。随着可穿戴传感器技术的出现，现在可以连续测量心率，从而有可能准确识别个体的“正常”心率，并随着时间的推移发现其潜在的重要变化。我们的目标是使用可穿戴设备描述两年内静息心率（RHR）的个体内和个体间变异性，研究静息心率随时间的变化，以及个体特征（如年龄、性别、平均睡眠时间和体重指数（BMI））对其的影响。
我们的回顾性、纵向队列研究包括来自美国（所有 50 个州）的 92457 名身份不明的个体，他们在 2016 年 3 月至 2018 年 2 月期间，至少持续 35 周，每周至少连续 2 天，每天至少 20 小时佩戴心率腕戴追踪器。在这项研究中，我们报告了每日 RHR 及其与年龄、BMI、性别和睡眠持续时间的关联，以及随时间的变化。个体每日 RHR 中位数可获得 320 天，提供了近 3300 万条每日 RHR 值。我们还探讨了个体之间每日 RHR 变异性的范围，以及个体每日 RHR 轨迹的长期和短期变化。平均每日 RHR 为 65 次/分钟（bpm），所有个体的范围为 40 至 109 bpm。RHR 均值因年龄、性别、BMI 和平均睡眠时间而异。还注意到季节变化，7 月最低，1 月最高。对于大多数受试者，RHR 在短期内相对稳定，但 20%的受试者至少有一周的 RHR 波动超过 10 bpm。
个体的每日 RHR 对他们来说是正常的，但与另一个个体的正常 RHR 可能相差多达 70 bpm。在个体内部，RHR 随时间的变化更为一致，具有较小但显著的季节性趋势，并可检测到正常范围外的离散且不频繁的事件。
