Department of Occupational Therapy and Physiotherapy, Sahlgrenska University Hospital, Gothenburg, Sweden.
Department of Neurobiology, Care Sciences and Society, Division of Physiotherapy, Karolinska Institutet, Stockholm, Sweden.
J Geriatr Phys Ther. 2019 Oct/Dec;42(4):E69-E76. doi: 10.1519/JPT.0000000000000204.
Accelerometer threshold values to detect physical activity intensity in the oldest old persons with coronary artery disease (CAD) are lacking as well as knowledge about their free-living physical activity behavior. The purpose of this study was 2-fold. (1) To assess the sensitivity and specificity of 3 existing intensity threshold values for ActiGraph accelerometers for the oldest old persons with CAD. (2) To assess free-living physical activity, applying the threshold values with the highest sensitivity and specificity for assessing at least moderate intensity, among these persons.
In a cross-sectional design, a total of 24 persons with CAD, mean age 87.5 (3.7) years, participated in the study at a university hospital in Sweden. To assess the sensitivity and specificity of the existing threshold values, the participants walked at different speeds wearing the accelerometer at a pace corresponding to individualized perceived exertion at light, moderate, and high intensity according to the Borg Rating of Perceived Exertion Scale. For the free-living physical activity assessment, the persons wore the accelerometer for 7 consecutive days. The percentage agreement for light-, moderate-, and high-intensity threshold values, as well as receiver operating characteristic curves, was used to identify the sensitivity and specificity of the existing threshold values for moderate intensity.
The threshold values for at least moderate intensity at 1041 counts per minute according to Copeland had the highest sensitivity (0.739) and specificity (0.609) to identify at least moderate intensity for the ActiGraph GT3X+ accelerometer. In a free-living setting, the oldest old persons with CAD spent 11 of 13.5 (81%) waking hours in a sedentary position and, of the 2.5 hours of being active, 19 minutes (2%) were at least at moderate intensity. Nine of 24 persons (38%) reached 20 minutes of moderate- to vigorous-intensity physical activity 3 days a week, according to guidelines for exercise-based cardiac rehabilitation.
The existing threshold values according to Copeland had the highest sensitivity and specificity to identify at least moderate intensity and are valid for use in the oldest old persons with CAD. Using accelerometry as an objective measurement for physical activity can help further improve our understanding of free-living physical activity behavior and to assess relationships between free-living physical activity and health outcomes among the oldest old persons with CAD.
缺乏针对患有冠状动脉疾病 (CAD) 的最年长老年人的加速度计活动强度检测阈值，也缺乏对他们的自由生活活动行为的了解。本研究的目的有两个。（1）评估现有的三种加速度计活动强度阈值在患有 CAD 的最年长老年人中的灵敏度和特异性。（2）在这些人中，应用具有最高灵敏度和特异性来评估至少中等强度的阈值，评估他们的自由生活体力活动。
在一项横断面设计中，共有 24 名患有 CAD 的老年人（平均年龄 87.5 [3.7] 岁）在瑞典的一所大学医院参加了研究。为了评估现有阈值的灵敏度和特异性，参与者穿着加速度计以与根据 Borg 感觉用力量表的轻、中、高强度对应的个人感知用力的速度行走。对于自由生活的体力活动评估，这些人佩戴加速度计连续 7 天。使用轻、中、高强度阈值的百分比一致性和接收者操作特征曲线，来确定至少中等强度的现有阈值的灵敏度和特异性。
根据 Copeland 的 1041 次/分钟的至少中等强度阈值具有最高的灵敏度（0.739）和特异性（0.609），可用于识别 ActiGraph GT3X+加速度计的至少中等强度。在自由生活环境中，患有 CAD 的最年长老年人在清醒状态下有 11 个小时（81%）处于久坐不动的状态，在 2.5 个小时的活动中，有 19 分钟（2%）达到至少中等强度。根据运动为基础的心脏康复指南，24 人中的 9 人（38%）每周达到 3 天，每天 20 分钟的中到剧烈强度体力活动。
根据 Copeland 的现有阈值具有最高的灵敏度和特异性，可用于识别至少中等强度，可用于患有 CAD 的最年长老年人。使用加速度计作为体力活动的客观测量可以帮助我们进一步了解自由生活体力活动行为，并评估患有 CAD 的最年长老年人中自由生活体力活动与健康结果之间的关系。
