Prevalence and impact of comorbid widespread pain in adults with chronic low back pain: A registry-based study

Introduction: Widespread pain (WP) is emerging as a key comorbid condition in patients with chronic low back pain (CLBP). This study measured the prevalence of comorbid WP in adults with CLBP, WP predictors, and impact on patients. Methods: Patients with CLBP were recruited from the Pain Registry for Epidemiologic, Clinical, and Interventional Studies and Innovation from 2016 through 2019. They were followed over 12 months to measure annual WP period prevalence rates using an item from the minimum dataset recommended by the National Institutes of Health Task Force on Research Standards for Chronic Low Back Pain. Patients were classified as not having WP, having nonpersistent WP, or having persistent WP. Pain intensity, back-related disability, and quality of life were measured using a numerical rating scale, the Roland-Morris Disability Questionnaire, and the PROMIS-29 instrument, respectively. Results: A total of 358 patients were studied, including 56 (16%) without WP, 272 (76%) with nonpersistent WP, and 30 (8%) with persistent WP. There were no significant differences among the WP groups with regard to age, sex, or CLBP duration. However, being non-White and having moderate or high levels of pain catastrophizing remained significant predictors of nonpersistent or persistent WP after adjusting for potential confounders. Patients reported greater pain intensity and back-related disability and poorer quality of life over 12 months with increasing levels of WP persistence (P < .001 for each measure). Conclusion: Greater efforts are needed in primary care to help close these gaps in pain intensity, back-related disability, and quality-of-life outcomes associated with WP.