Pain interference with sleep and mobility in youth with cerebral palsy: a systematic review and meta-analysis

Background and Aims: Cerebral palsy (CP) is commonly associated with musculoskeletal, neurological, and gastrointestinal conditions that lead to pain. The prevalence of pain in children with CP ranges from 14-76% [1], varying due to the type of CP, Gross Motor Function Classification System (GMFCS) level, age at assessment of pain, location of pain, and/or the method of reporting. The extent to which pain interferes in cognitive, physical, and social activities of individuals with CP has not been explored. Therefore, the aim of this systematic review and meta-analysis was to determine the extent to which pain interferes with sleep and mobility in youth with CP. Methods: We searched six electronic databases from inception to April 2020 for primary research that sampled individuals with CP who were younger than 25 years of age, and that measured pain interference in sleep and/or mobility. Articles were screened independently by two reviewers at title, abstract, and full-text stages, and disagreements were resolved by a third reviewer. Risk of bias was assessed using the modified Strengthening the Reporting of Observational Studies in Epidemiology [2] checklist, which evaluated the appropriateness and validity of the study design. The primary variables of interest were pain interference with mobility and sleep among children and young adults with CP. Data were analysed using two methods: a pooled prevalence estimate of pain interference on mobility and sleep, and a descriptive analysis of unpooled studies. This review is prospectively registered on PROSPERO (CRD42020159083). Results: Out of 1,040 records screened, 15 studies (6 = mobility; 9 = sleep) were eligible for inclusion in this review, all which were cross-sectional. Participants (N = 4,837, 53-79% males, all GMFCS levels) were between three and 20 years of age. Pain interference measures included standardized self- or proxy- (parent or clinician) reported questionnaires including Brief Pain Inventory and Patient Reported Outcomes Measurement Information. Pain-relieving strategies implemented were not consistently reported within studies. The overall prevalence of pain reported ranged from 61-94%. Two studies were able to be pooled for mobility, and six for sleep due to between-study heterogeneity. Pain interference with mobility ranged from 10-58% overall, with the pooled prevalence estimate being 21% (95%CI=14-29%, I2=52%). Pain interference with sleep ranged from 5-36%, with the pooled prevalence estimate being 30% (95%CI=16-46%, I2=94%). Subgroup analyses were only able to be performed on the sleep data due to differences in the collection of data and samples in the mobility data. Studies which recruited samples that had comparable GMFCS levels to global rates revealed a pooled prevalence estimate of 35% (95%CI=32-38%, I2=8.8%). Other subgroup analyses on the sleep data showed high statistical heterogeneity (all χ2 tests > 0.05) including region where the study was conducted, type of reporting method, and variability in GMFCS levels. Conclusions: There is a high and variable prevalence of pain interference on mobility and sleep in children, adolescents, and young adults with CP. Clinicians are recommended to assess and treat pain, as well as monitor the impact of pain on mobility and sleep. 1. Tedroff K, Gyllensvärd M, Löwing K. Prevalence, identification, and interference of pain in young children with cerebral palsy: a population-based study. Disabil Rehabil 2019;16:1-7.