Disrupted rest-activity circadian rhythm is associated with an increased prevalence of chronic respiratory diseases (CRDs) in adults, according to study findings published in Respiratory Medicine.
Researchers used 24-hour objective actigraphy data to assess the association of rest-activity circadian rhythm with CRDs in US adults who are participants in the Centers for Disease Control and Prevention’s National Health and Nutrition Examination Survey (NHANES). The 7412 participants in the current study were 20 years of age and older and had available accelerometer data for 2011 to 2012 and 2013 to 2014. Participants’ average age was 48.54 years, 51.79% were female, and 68.29% were non-Hispanic White. CRD prevalence rates were 2.05% for emphysema, 6.01% for chronic bronchitis, and 15.35% for asthma.
Rest-activity circadian rhythm indices were calculated and classified into quartiles: the lowest quartile of intradaily variability (IV), the least active continuous 5-hour period (L5), L5 start time, and the most active continuous 10-hour period (M10) start time. The highest quartile of interdaily stability (IS), relative amplitude (RA), and M10 were considered the reference groups. General linear models adjusted for age were used to compare rest-activity circadian rhythm indices among patients and healthy participants. Binary logistic regression analysis was used to calculate odds ratios (ORs). The main outcomes were CRDs (ie, emphysema, chronic bronchitis, and asthma).
Patients with emphysema, chronic bronchitis, and asthma had a lower value of RA vs corresponding healthy participants (all P <.05). Among patients with chronic bronchitis and asthma, L5 was significantly lower compared with healthy participants (all P <.05).
RA was associated with the 3 CRDs after adjustment for potential covariates. Participants in the highest quartile had the lowest prevalence of emphysema (OR, 0.43; 95% CI, 0.21-0.88), chronic bronchitis (OR, 0.65; 95% CI, 0.43-0.99), and asthma (OR, 0.70; 95% CI, 0.56-0.87), compared with those in the lowest quartile of RA. The highest intradaily variability quartile was associated with a higher prevalence of emphysema compared with the lowest quartile (OR, 2.35; 95% CI, 1.42-3.89). Individuals who were in the highest M10 quartile had a lower emphysema prevalence vs those in the lowest quartile (OR, 0.13; 95% CI, 0.06-0.30).
In this representative US adult study, we concluded that disrupted 24-hour rest-activity circadian rhythm is associated with a higher prevalence of emphysema, chronic bronchitis, and asthma.
Participants in the highest quartile of L5 and L5 start time had a higher prevalence of asthma, compared with those in the lowest quartile of L5 and L5 start time (OR, 1.60; 95% CI, 1.25-2.06 for L5; OR, 1.25; 95% CI, 1.01-1.57 for L5 start time).
Nonlinear correlations were observed regarding the association of RA with emphysema, chronic bronchitis, and asthma (all P for nonlinear <.05). Among participants with a high RA level (>0.8), the ORs for the 3 CRDs increased concomitantly with increasing RA in a dose-response relationship.
Sensitivity analysis showed that the associations between rest-activity circadian rhythm indices and emphysema and asthma remained significant after adjustment for comorbidities of CRDs (all P <.05).
Study limitations include the cross-sectional design and the fact that all participants were US adults. Also, biomarkers of internal circadian rhythms or environmental cues such as light exposures, daily schedule, and shift work were not analyzed.
“In this representative US adult study, we concluded that disrupted 24-hour rest-activity circadian rhythm is associated with a higher prevalence of emphysema, chronic bronchitis, and asthma,” stated the study authors. “Our study shed new light on the role of rest-activity circadian rhythm in CRDs.”