Association between chronotype preference and sleep characteristics in insomnia patients

The relationship between chronotype preference and subjective sleep perception, objective sleep parameters, rest-activity rhythms (RAR), as well as light exposure rhythms (LER) in insomnia patients remains insufficiently clarified. This study aimed to explore the differences in nocturnal and diurnal sleep characteristics, RAR and LER between morning-type and intermediate-type insomnia patients, and to screen subjective and objective influencing factors associated with chronotype preference.

A total of 62 enrolled insomnia patients were divided into morning-type and intermediate-type groups according to the Morningness-Eveningness Questionnaire (MEQ). All participants completed relevant subjective scales including the Sleep Hygiene Practice Scale (SHPS) and underwent 7-day continuous wrist actigraphy monitoring. RAR and LER non-parametric indicators were calculated via R software. Group differences in demographic data, subjective sleep scales, and actigraphy-derived nocturnal and diurnal variables were compared, and multivariate linear regression was performed to identify predictors of MEQ scores.

Compared with intermediate-type patients, morning-type insomnia patients were significantly older, with poorer subjective sleep quality and more irrational sleep beliefs, and showed higher daytime rhythm stability and more regular activity patterns (all P < 0.05). No significant inter-group differences were observed in most objective sleep parameters. Multivariate linear regression analysis confirmed that SHPS score and the timing of the most active 10 h (M10) were independent influencing factors of chronotype preference.

Chronotype preference is closely correlated with age, subjective sleep perception, sleep hygiene level and rest-activity rhythm characteristics. Attention should be paid to individual chronotype characteristics in clinical insomnia management, optimizing sleep hygiene and regulating daily activity rhythm patterns may help improve sleep status in insomnia patients.