Behavioral-social rhythms and cardiovascular disease risk in retired night shift workers and retired day workers

Abstract

Abstract Objective Stability in the timing of key daily routine behaviors such as working/doing housework, sleeping, eating, and engaging in social interactions (i.e., behavioral–social rhythms) contributes to health. This study examined whether behavioral–social rhythms were associated with CVD risk factors in retired night shift workers and retired day workers and explored whether past night shift work exposure moderated this association. Methods 154 retired older adults participated in this study. Multiple logistic regression models were used to examine associations between behavioral–social rhythms and CVD risk factors. Independent variables included Social Rhythm Metric (SRM)-5 score and actigraphy rest-activity rhythm intra-daily variability (IV) and inter-daily stability (IS). Dependent variables were metabolic syndrome prevalence and its five individual components. Results More regular behavioral-social rhythms were associated with lower odds of prevalent metabolic syndrome (SRM: OR = 0.57, 95% CI [0.35, 0.88]; IV: OR = 4.00, 95% CI [1.86, 8.58]; IS: OR = 0.42, 95% CI [0.24, 0.73]) and two of its individual components: body mass index (SRM: OR = 0.56, 95% CI [0.37, 0.85]; IV: OR = 2.84, 95% CI [1.59, 5.07]; IS: OR = 0.42, 95% CI [0.26, 0.68]) and high-density lipoprotein cholesterol (SRM: OR = 0.49, 95% CI [0.30, 0.80]; IV: OR = 2.49, 95% CI [1.25, 4.96]; IS: OR = 0.35, 95% CI [0.19, 0.66]). Past shift work history did not moderate the association between behavioral–social rhythms and metabolic syndrome. Conclusions Behavioral–social rhythms were related to CVD risk factors in retired adults regardless of prior night shift work exposure. Older retired workers may benefit from education and interventions aiming to increase behavioral–social rhythm regularity.