Sleep Quality in Chronic Pain Patients With and Without Strong Opioid Use: An Observational Study Using a Wearable Device.

Background: Although opioid analgesics may influence sleep in patients with chronic pain, the association between strong opioid use and sleep characteristics remains unclear. This study aimed to explore differences in sleep status among chronic pain patients with varying levels of opioid use.

Methods: A total of 29 patients with chronic non-cancer pain who had been under treatment for more than 6 months were included. Patients were divided into four groups based on their opioid use: non-opioid users (n = 11), weak opioid users (n = 8), and strong opioid users receiving either < 60 mg/day (n = 5) or ≥ 60 mg/day (n = 5) in morphine-equivalent doses. Pain and psychological factors were assessed using the Numerical Rating Scale, Pain Catastrophizing Scale, Hospital Anxiety and Depression Scale, and Japanese Perceived Stress Scale. Subjective sleep status was assessed using the Athens Insomnia Scale. Objective sleep parameters, including total sleep duration, wakefulness after sleep onset (WASO), and sleep efficiency, were measured over seven nights using the wearable device. Sleep data were analyzed using a linear mixed-effects model with the opioid-naive group as the reference. Model 1 was unadjusted; Model 2 adjusted for age, sex, pain intensity, catastrophizing, anxiety, depression, and stress.

Results: Patients in the ≥ 60 mg/day group showed shorter total sleep duration, longer WASO, and lower sleep efficiency in Model 1 compared to non-opioid users. These trends remained in Model 2, although statistical significance decreased. In contrast, those receiving < 60 mg/day showed trends toward shorter WASO and higher sleep efficiency. Subjective insomnia symptoms were more frequent in both strong opioid groups, especially in the high-dose group.

Conclusion: Among patients with chronic non-cancer pain, high-dose strong opioid use tended to be associated with poorer sleep, while low-dose use was linked to more favorable sleep characteristics.