In this retrospective observational study, we summarize our initial experience in creating a multidisciplinary clinic and in delivering care for young adults with chronic pain and sleep health impairments. We report notable sleep disturbances in this cohort that had females in the majority (71%). The most encountered pain diagnosis in this cohort was chronic widespread pain or fibromyalgia, present in 35% of the patients. Sleep data were available in 47 patients and majority (83%) had symptoms of disorders of sleep.
Several studies have shown that young adults with chronic pain report greater sleep disturbances and poorer sleep quality compared to their healthy counterparts.27–32 Here, we evaluated the impact of pain on sleep health by assessing major sleep health domains - sleep efficacy, sleep timing, alertness, sleep quality, and sleep duration. Although mean sleep duration in our cohort was 7.9 ± 4.8 hours in patients with symptoms of disorders of sleep at night and 9.3 ± 8.0 hours in those with no symptoms implying that sleep duration is minimally affected by the experience of pain. However, the assumed refreshing effect of sleep in these patients was questionable because 25 (53%) of the patients complained of waking up unrefreshed and 9/32 (28.13%) had increased daytime sleepiness as per their ESS scores (i.e., ESS score more than 10/24). Previous studies have also suggested that although youth with chronic pain demonstrate similar sleep latency, sleep efficiency, and sleep duration when compared to those without chronic pain, they still report greater insomnia symptoms and spend more time sleeping during the day.30,33−39
Systematic reviews on children and young adults with chronic pain found high rates of sleep impairment among these patients.28 While previous studies have reported sleep deficiency in more than 50% of youth with chronic pain, here we found symptoms of disorders of sleep in ~ 83% of our sample.27,40 We found heterogenicity in sleep disorders among these patients including insomnia (68.1%), sleep-related movement disorder (14.9%), circadian rhythm disorder (30.4%), parasomnia (2.13%), and sleep disordered breathing disorders (25.5%). Our study sample (71% female) is also consistent with previously published studies that show chronic pain disorders have a higher prevalence in females,1,32,41 with female patients reporting poorer sleep quality than males.42 This high proportion of patients with symptoms of disorders of sleep in our sample highlights the need for sleep assessment and outcomes to be integrated in comprehensive pain management. Despite the prevalence of poor sleep health in young adults with chronic pain, sleep health is often overlooked during chronic pain assessments and care plan. This is exemplified by a recent systematic review that included 75 studies with 78,364 young adults with chronic pain, in which only five studies reported assessing the association between sleep problems and chronic pain.32
Several studies report that sleep and pain interact in a bidirectional manner in adolescents with chronic pain. 28,33 Furthermore, the effect of sleep deficiency on pain may be stronger than the effect of pain on sleep.11 Recent evidence suggests that sleep deficits may result in the development of new-onset chronic pain or worsen pain and disability in individuals with pre-existing pain.27,28,33,40 43 Collectively these findings again highlight the need for sleep health assessment and clinical follow up in order to support chronic pain management and potentially the prevention of new-onset pain in young adults with chronic pain. While the current study does not address the directionality or timing of chronic pain and symptoms of disorders of sleep, we do find that young adults with symptoms of sleep disorder have lower pain self-efficacy. Future studies that evaluate the impact of clinical sleep interventions on this population are required to determine whether early intervention can improve pain and mitigate the onset of new pain or worsening disability.
The impact of various medications used for chronic pain management on sleep should also be considered. Most commonly used medication by patients in our cohort were anticonvulsants such as gabapentin and pregabalin that improved sleep disturbance in patients with chronic pain syndromes 44,45 but also contributed to increased daytime somnolence, a dose-dependent adverse effect.46 Given the relationship between sleep health and chronic pain symptoms and prognosis, the impact of medications on both pain and sleep outcomes should be carefully considered.
It is recognized that poor coping (low pain self-efficacy scores, high catastrophizing) and mental health conditions such as depression can adversely impact sleep health and quality of life. In our study, there was a trend toward increased PHQ-9 score in patients with symptoms of disorders of sleep at night compared to those without these symptoms. A study by Gregory and O’Connor 47 reported that increase in depressive symptoms was associated with sleep impairments in youth. MacGregor et al. also demonstrated that Item 3 of the PHQ-9 (“Trouble falling or staying asleep, or sleeping too much”) shows promise as a screener for sleep problems in primary care.48 However, our study showed no difference in the incidence of depression in those with no symptoms of disorders of sleep (93%) compared to those with symptoms of disorders of sleep (91%). Seventeen (37%) of the patients in our cohort were at a high risk of pain-related catastrophizing as indicated by their PCS scores. However, there was no significant difference between those with sleep disorders and those with no sleep disorders. There was a higher prevalence of low pain self-efficacy in patients with symptoms of disorders of sleep at night compared to those with no symptoms, with mean PSEQ scores of 24.90 ± 13.2 and 34.43 ± 16.9 (p = 0.041) and prevalence of 57.6% and 21.4% (p = 0.023), respectively. Self-efficacy beliefs play an important role in functioning and coping with chronic pain. It is an important determinant of disability and is strongly related to treatment outcome.49,50 Additionally, pain catastrophizing thoughts are more often associated with patients suffering greater sleep disturbance as suggested by Buenaver et al. in their study for patients with myofascial temporomandibular disorder.15 These findings suggest that problems related to sleep are not necessarily a secondary issue and deserve more attention to identify other effective ways to improve sleep quality and reduce pain in young people.
Our study has a few limitations including a small sample size and its retrospective nature. Our sample is not representative of the general population of all young adults suffering from chronic pain and the results should be interpreted with caution. We could only demonstrate that sleep disturbances are commonly found in young adults with chronic pain and we have elaborated on the nature of sleep problems. Any causality or any other association cannot be established by our study. Further, not all young adult patients with pain were seen by the sleep specialist. We also do not have data on the intensity of pain and the daily opioid doses for patients who were on this group of medications.