Background The effects of aging on circadian patterns of behavior are insufficiently described. To address this, we characterized age-specific features of rest-activity rhythms (RAR) in community dwelling older adults both overall, and in relation, to sociodemographic characteristics. Methods We examined cross-sectional associations between RAR and age, sex, race, education, multimorbidity burden, financial, work, martial, health, and smoking status using assessments of older adults with wrist-worn free-living actigraphy data (N=820, Age=76.4 yrs, 58.2% women) participating in the Study of Muscle, Mobility and Aging (SOMMA). RAR parameters were determined by mapping an extension to the traditional cosine curve to activity data. Functional principal component analysis determined variables accounting for variance. Results Age was associated with several metrics of dampened RAR; women had stronger and more robust RAR vs. men (all P < 0.05). Total activity (56%) and time of activity (20%) accounted for most the RAR variance. Compared to the latest decile of acrophase, those in the earliest decile had higher average amplitude (P <0.001). Compared to the latest decile of acrophase, those in the earliest and midrange categories had more total activity (P=0.02). Being in a married-like relationship and a more stable financial situation were associated with stronger rhythms; higher education was associated with less rhythm strength (all P < 0.05). Conclusions Older age was associated with dampened circadian behavior; behaviors were sexually dimorphic. Some sociodemographic characteristics were associated with circadian behavior. We identified a behavioral phenotype characterized by early time-of-day of peak activity, high rhythmic amplitude, and more total activity.

中文翻译：

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年龄与休息和活动的昼夜节律模式减弱有关：肌肉、活动性和衰老的研究 (SOMMA)

背景 衰老对昼夜节律行为模式的影响尚未得到充分描述。为了解决这个问题，我们描述了社区居住老年人的休息活动节律（RAR）的总体特征以及与社会人口特征的关系。方法 我们使用腕戴式自由活动记录仪数据对老年人进行评估，研究了 RAR 与年龄、性别、种族、教育、多重疾病负担、经济、工作、军事、健康和吸烟状况之间的横断面关联（N=820） ，年龄 = 76.4 岁，58.2% 女性）参与肌肉、活动性和衰老研究 (SOMMA)。RAR 参数是通过将传统余弦曲线的延伸映射到活动数据来确定的。功能主成分分析确定了解释方差的变量。结果 年龄与 RAR 减弱的几个指标相关；与男性相比，女性的 RAR 更强、更稳健（所有 P < 0.05）。总活动 (56%) 和活动时间 (20%) 是 RAR 方差的主要原因。与末期最晚十分位相比，最早十分位的平均振幅更高（P＜0.001）。与末期十分位相比，最早和中期类别的总活性更高（P=0.02）。处于类似婚姻的关系和更稳定的财务状况与更强的节奏有关；较高的教育程度与较低的节律强度相关（所有 P < 0.05）。结论 年龄较大与昼夜节律行为减弱有关；行为是性别二态性的。一些社会人口学特征与昼夜节律行为相关。我们确定了一种行为表型，其特征是一天中的早期活动高峰、高节律幅度和更多的总活动。