Patient-reported outcome measures in patients with systemic lupus erythematosus with or without concurrent fibromyalgia

Objective Patients with systemic lupus erythematosus (SLE) often have concomitant fibromyalgia (FM) or similar symptoms including chronic pain, fatigue, or depression. This study explored whether Patient-Reported Outcomes Measurement Information System (PROMIS) measures provide richer information than 2016 American College of Rheumatology (ACR) FM criteria survey. Methods Patients with SLE in our convenience cohort were categorized into groups: (1) concurrent FM chronic pain, (2) concurrent non-FM chronic pain, and (3) no chronic pain using 2016 ACR FM Survey. Based on PROs in the FM Survey, we captured comparable PROMIS measures (e.g., depression, fatigue). Associations by pain group were tested using Kruskal-Wallis rank sum test, Shapiro-Wilk normality test, chi-squared test, or Fisher’s exact test. Violin plots explored differences across groups. Results The cohort ( n = 181) included 31 patients with FM pain, 23 with non-FM chronic pain, and 127 with no chronic pain. Median PROMIS symptom scores (fatigue, sleep disturbance, pain intensity and interference, depression) were highest and cognitive function lowest in the FM group, despite 13% being in remission. There were significant differences on 4 PROMIS measures (cognitive function, fatigue, pain intensity, pain interference) between FM pain and non-FM pain groups ( p < .02), the former being worse. There were no significant differences in SLE Disease Activity Index (SLEDAI) score. Conclusion SLE patients with non-FM chronic pain have similar symptoms to FM compared with SLE patients without chronic pain; however, symptoms are not as severe as those meeting FM criteria. PROMIS measures may be used to classify severity more precisely for disease categorization and management.