Background Little is known as to how rest-activity rhythms (RAR) are associated with frailty and how this relationship differs by sex. This study examined the relationship between RAR and frailty in a nationally representative sample of US older adults, focusing on the moderating role of sex. Methods 2,531 participants aged ≥60yrs [Females:55.2%; Frail:5.15% (4.02–6.29); Pre-frail:33.49% (31.29–35.68)] were included using the 2011-2014 National Health and Nutrition Examination Survey. Non-parametric RAR parameters, including inter-daily stability (IS), intra-daily variability (IV), relative amplitude (RA), most active 10-h, and least active 5-h, were estimated from wrist-worn actigraphy data. Frailty status was assessed using a modified version of frailty phenotype (range:0–5): frail (≥3), pre-frail (1–2), and non-frail (0). Multinomial logistic regression models were used to examine the interest of associations, adjusting for potential confounders. Results Frail and pre-frail older adults exhibited significantly lower RA, IS, higher IV, and phase delay when compared to non-frail older adults (p’s<.05). Particularly, older adults with low RA had significantly greater odds of being frail and pre-frail [aOR(95%CIs); Frailty:5.60(2.61–12.04); Pre-frailty:1.58(1.13–2.20)]. Significant sex-interaction was observed (p<.01), with this association being greater in females than in males [aOR(95%CIs); Females:7.78(2.98–20.30) for frailty, 2.31(1.60–3.32) for pre-frailty; Males:4.48(1.38–14.54) for frailty, 1.12(0.61–2.07) for pre-frailty]. Conclusion Weakened RAR strength is unfavorably associated with frailty, particularly in females. RAR may be a useful indicator associated with frailty in older adults, but sex-specific differences should be considered. Further longitudinal research is necessary to investigate the bidirectionality of their association.

中文翻译：

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美国老年人 24 小时静息活动节律与虚弱之间关联的性别差异：NHANES 2011-2014 的结果


背景 关于静息活动节律 （RAR） 如何与虚弱相关以及这种关系如何因性别而异，知之甚少。本研究在具有全国代表性的美国老年人样本中检验了 RAR 与虚弱之间的关系，重点关注性别的调节作用。方法 2,531 名参与者年龄≥ 60 岁 [女性：55.2%;虚弱：5.15% （4.02–6.29）;衰弱前期：33.49% （31.29–35.68）] 被纳入 2011-2014 年全国健康和营养检查调查。非参数 RAR 参数，包括日间稳定性 （IS） 、日内变异性 （IV） 、相对振幅 （RA） 、最活跃的 10 小时和最不活跃的 5 小时，都是从腕戴式活动记录仪数据中估计的。使用衰弱表型的修改版本（范围：0-5）评估衰弱状态：衰弱 （≥3）、衰弱前期 （1-2） 和非衰弱 （0）。多项式 logistic 回归模型用于检查关联的兴趣，并针对潜在的混杂因素进行调整。结果 与非虚弱老年人相比，虚弱和前衰弱的老年人表现出显著降低的 RA 、 IS 、较高的 IV 和相位延迟 （p's<.05）。特别是，RA 低的老年人虚弱和前衰的几率明显更高 [aOR（95%CIs）;虚弱度：5.60（2.61–12.04）;衰弱前期：1.58（1.13–2.20）]。观察到显着的性互动 （p<.01），这种关联在女性中大于在男性中 [aOR（95%CIs）;女性：衰弱为 7.78（2.98–20.30），衰弱前期为 2.31（1.60–3.32）;男性：4.48（1.38-14.54） 为衰弱前期，1.12（0.61-2.07） 为衰弱前期]。结论 RAR 强度减弱与虚弱呈不利关系，尤其是女性。RAR 可能是与老年人虚弱相关的有用指标，但应考虑性别特异性差异。 需要进一步的纵向研究来调查它们关联的双向性。