OBJECTIVE: To investigate the associations between sleep parameters, specifically duration and efficiency, and circadian activity and blue light exposure (BLE) in children and adults within a family environment.
MATERIAL AND METHODS: In May 2025, a week-long actigraphic study was conducted in Tyumen, Russia, with 177 participants, comprising 88 children (mean age 10.56±2.17 years; 52.3% female) and 89 adults (mean age 37.56±8.14 years; 86.5% female). The study assessed sleep duration (SD), sleep efficiency (SE), relative nonparametric circadian activity amplitude (RA), intra-daily variability of BLE (BLE IV), inter-daily stability of BLE (BLE IS), and the integral index of light hygiene, defined as normalized parametric amplitude BLE (NA CC). Statistical analyses included nonparametric tests, correlation analysis, and linear regression models adjusted for sex and age.
RESULTS: Children demonstrated significantly longer sleep duration (by 49 minutes; 8:16±0:57 h vs. 7:27±1:04 h;0.001) and higher sleep efficiency (90.70±3.44% vs. 89.01±5.36%;0.031) compared to adults. Additionally, children exhibited a higher NA CC (1.48±0.19 vs. 1.42±0.17,0.016). Sleep duration and efficiency were positively correlated (=0.300,0.0001). RA was identified as a strong independent predictor of both SD and SE across all groups (0.001;²=0.142-0.276). Among adults, higher SE was significantly associated with greater BLE inter-daily stability (=0.253,0.017;=0.248,0.019) and lower BLE intra-daily variability (=-0.221,0.038;=-0.257,0.016). p< p= p= r p< p< η r p= β p= r p= β p=
CONCLUSIONS: Children exhibit greater sleep duration and efficiency, as well as more robust circadian rhythmicity, compared to adults. In adults, consistent daily blue light exposure, particularly inter-daily stability, is a key determinant of sleep quality. These findings underscore the significance of circadian light hygiene within the family environment and support the implementation of biodynamic lighting to enhance sleep quality across age groups.
