Intramural Research Program, National Institute on Aging, Baltimore, Maryland, USA.
Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, Washington, USA.
J Am Geriatr Soc. 2020 Oct;68(10):2297-2302. doi: 10.1111/jgs.16657. Epub 2020 Jul 3.
BACKGROUND/OBJECTIVES: Anemia is a common condition in older adults for which fatigue, the primary symptom, often goes unrecognized as individuals typically equilibrate their activity to avoid fatigue. Whether assessing fatigability (i.e., susceptibility to fatigue) facilitates identification of anemia is unknown. This study examines the association between fatigability and prevalent, incident, and persistent subclinical and clinical anemia in well-functioning older adults.
DESIGN, SETTING, PARTICIPANTS: Longitudinal analysis of 905 well-functioning men and women aged 60 to 89 years and followed for 1 to 5 years from the Baltimore Longitudinal Study of Aging conducted at the National Institute on Aging, Clinical Research Unit, Baltimore, MD.
Perceived fatigability was assessed as a rating of perceived exertion (RPE) from 6 to 20 following a 5-minute treadmill walk at 1.5 mph (.67 m/s); fatigue was assessed as reported unusual tiredness in the past month. Clinical anemia was defined using World Health Organization hemoglobin cutpoints of below 13 g/dL and below 12 g/dL for men and women, respectively, and subclinical anemia was defined as 13.0 to 13.9 g/dL and 12.0 to 12.9 g/dL, respectively.
Overall, 14% of participants had clinical and 30% had subclinical anemia at baseline. Each increment (1 RPE) of fatigability was associated after covariate adjustment with 14% (95% confidence interval [CI] = 5-25%, P = .005) and 8% (CI = 1-17%; P = .031), respectively, greater likelihood of prevalent clinical and subclinical anemia. An average of 2.2 years later, each 1 RPE increment in baseline fatigability predicted an 11% (CI = 2-20%; P = .016) higher likelihood of incident and/or persistent subclinical and clinical anemia. Reports of unusual tiredness were associated with prevalent subclinical anemia only.
This study provides evidence that perceived fatigability may help identify well-functioning older adults with borderline to clinical anemia who are on a trajectory of persistently suboptimal or worsening hemoglobin status. Assessing fatigability may facilitate earlier diagnosis of health conditions that underlie persistent suboptimal hemoglobin status. J Am Geriatr Soc 68:2297-2302, 2020.
背景/目的：贫血是老年人的一种常见病症，其主要症状是疲劳，但由于个体通常会调整活动以避免疲劳，因此这种症状常常未被识别。目前尚不清楚评估疲劳感（即疲劳易感性）是否有助于确定贫血。本研究旨在探讨在功能良好的老年人中，疲劳感与普遍存在的、新发的、持续性亚临床和临床贫血之间的关系。
设计、地点、参与者：这是一项来自巴尔的摩老龄化纵向研究的纵向分析，该研究在马里兰州巴尔的摩国家老龄化研究所临床研究单位进行，共纳入 905 名年龄在 60 至 89 岁之间、功能良好的男性和女性，随访时间为 1 至 5 年。
疲劳感通过在 1.5 英里/小时（.67 m/s）的跑步机上行走 5 分钟后的感知用力等级（RPE）评分从 6 到 20 进行评估；疲劳感通过报告过去一个月中不寻常的疲倦感进行评估。临床贫血使用世界卫生组织的血红蛋白切点定义，男性血红蛋白<13 g/dL 和女性血红蛋白<12 g/dL，亚临床贫血定义为男性血红蛋白 13.0 至 13.9 g/dL 和女性血红蛋白 12.0 至 12.9 g/dL。
总体而言，在基线时，14%的参与者患有临床贫血，30%的参与者患有亚临床贫血。在调整协变量后，疲劳感每增加 1 个等级（RPE），分别与 14%（95%置信区间[CI] = 5-25%，P = .005）和 8%（CI = 1-17%；P = .031）的普遍存在的临床和亚临床贫血的可能性增加相关。平均 2.2 年后，基线疲劳感每增加 1 个 RPE 等级预示着新发和/或持续性亚临床和临床贫血的可能性增加 11%（CI = 2-20%；P = .016）。不寻常的疲倦感仅与亚临床贫血相关。
本研究提供了证据表明，疲劳感可能有助于识别处于亚临床贫血和临床贫血边缘的功能良好的老年人，这些老年人的血红蛋白状态可能持续处于不理想或恶化的状态。评估疲劳感可能有助于更早地诊断出导致血红蛋白状态持续不理想的健康状况。美国老年学会杂志 68：2297-2302，2020 年。
