Sleep and circadian parameters in Behçet's syndrome: a comparative analysis using actigraphy and questionnaires

Sleep disturbances are highly prevalent in Behçet syndrome (BS) patients. Within this population, sleep disturbances are frequently associated with active disease and comorbid fibromyalgia. However, possible sleep impairments in BS patients without these conditions remain poorly explored, along with BS patients' obstructive sleep apnoea syndrome (OSAS) risk and circadian rhythm preferences. We aimed to address these research gaps through a cross-sectional study comparing sleep and circadian parameters between BS patients, with or without active disease and comorbid fibromyalgia, and healthy controls (HCs).

Participants' sleep and circadian parameters were evaluated objectively via actigraphy and subjectively through the Pittsburgh Sleep Quality Index and the reduced Morningness-Eveningness Questionnaire. A comprehensive clinical evaluation investigated sociodemographic data, disease activity and comorbid fibromyalgia. Possible predictors of sleep and circadian parameters were tested estimating linear regression models.

Forty-five BS patients and 61 age-, BMI-, sex- and smoking habits-matched HCs were enrolled. Only BS patients with active disease and/or fibromyalgia showed significantly lower sleep quality, significantly higher sleep fragmentation and a tendence towards less robust circadian rhythms compared to other participants. Instead, BS patients without those conditions did not significantly differ from HCs in sleep and circadian parameters. Furthermore, a higher actigraphically-determined OSAS risk was found in all BS patients compared to HCs.

Active disease and fibromyalgia are associated with sleep and circadian rhythm disturbances in BS patients. Screening for sleep and circadian rhythm disturbances may be advised in BS patients with these conditions, while OSAS screening may be recommended in all BS patients with sleep disturbances.