Evidence that taking opioids will help people with chronic pain to sleep better is limited and of poor quality, according to an interdisciplinary team of psychologists and medics from the University of Warwick in partnership with Lausanne University Hospital, Switzerland.
Many people suffering from long-term chronic pain use opioids as a sleep aid to take away pain and stop their sleep being disrupted. However, a new study led by the Department of Psychology at the University of Warwick with Warwick Medical School suggests that not enough research has been done to assess the benefits and risks of using painkillers for the purpose of improving sleep quality.
Their study, a systematic review of existing research on the effects of opioids on sleep, has been published in Sleep Medicine Reviews.
Sleep disruption is a particularly frequent issue for patients with chronic pain, with a vicious cycle building between bad nights and increased pain. Patients with chronic pain are often empirically prescribed opioids to reduce their pain enough to get a good night’s sleep, but there has been little investigation of whether this is a safe and effective intervention.
The researchers conducted a comprehensive systematic review of existing literature that examined the effects of opioids on sleep quality. As part of this, they conducted a meta-analysis of data from these studies, combining the results of 18 studies which were then narrowed down to 5 with comparable data.
They found that research on opioid effects on sleep quality was limited and of poor quality, often with potential publication bias and conflicts of interest, and rarely testing patients for sleep apnea prior to and during the study.
Patients reported a small improvement in sleep quality when using opioids but that was not consistent with results derived from sleep assessment technologies, such as the total time and the percentage of time in deep sleep, which did not show an improvement.
Certain studies reported calmer sleep with less movement but the examined articles frequently did not examine the wider effects of opioid therapy such as subsequent functioning during the day. Where they did, reports of sedation