The association between depressive symptoms or depression and health outcomes in adults with low back pain with or without radiculopathy: protocol of a systematic review

BACKGROUND: A considerable proportion of adults with low back pain (LBP) suffer from depressive symptoms or depression. Those with depressive symptoms or depression may be at risk of poorer LBP recovery and require more health care. Understanding the role of prognostic factors for LBP is critically important to guide management and health services delivery. Our objective is to conduct a systematic review to assess the association between depressive symptoms or depression and health outcomes in adults with LBP with or without radiculopathy. METHODS: Electronic databases including MEDLINE, Embase, CINAHL, and PsycINFO will be searched from inception to April 2019 to identify relevant studies. Additional citations will be identified by searching reference lists of included studies and related systematic reviews. Cohort and case-control studies assessing the association between depressive symptoms/depression and health outcomes in adults aged 16 years and older with LBP with or without radiculopathy will be included. The following will be included: depressive symptoms as measured on standardized questionnaires (e.g., Center for Epidemiologic Studies Depression Scale, Beck Depression Index), and depression as standardized diagnoses (e.g., International Classification of Diseases codes) or self-reported depression diagnosis on standardized questionnaires. Outcomes of interest are standardized measures for pain, disability, overall health status, satisfaction with care, and health care utilization. These are informed by core outcome domains that international expert panels consider important for LBP research. Pairs of reviewers will screen articles retrieved from the search, extract data, and assess risk of bias using the Risk Of Bias In Non-randomized Studies-of Exposures (ROBINS-E) tool. Reviewers will use these criteria to inform their judgment on the internal validity of studies (e.g., low, moderate, or high risk of bias). If studies are deemed homogeneous, a random effects meta-analysis on the association between depressive symptoms and health outcomes will be performed. The results of the included studies will be descriptively outlined if studies are deemed heterogeneous. DISCUSSION: The impact of depressive symptoms and depression on health- and health care-related outcomes for LBP with or without radiculopathy will be assessed and quantified. Findings of this systematic review will advance our understanding of LBP prognosis, and guide decision-making and improve quality of care for adults with LBP. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42019130047