Prevalence and impact of pain in childhood-onset systemic lupus erythematosus and juvenile dermatomyositis: retrospective review of the CARRA Legacy Registry

The prevalence, severity, and impact of pain in pediatric patients with autoimmune diseases such as childhood-onset SLE (cSLE) and juvenile dermatomyositis (JDM) have yet to be well studied. This study used the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Registry to (1) establish the prevalence of pain in pediatric patients with cSLE, lupus-spectrum diseases, and JDM and (2) explore the relationship between pain severity and pain interference. All patients 8 years and older diagnosed with lupus-spectrum diseases (SLE, MCTD, APS, Sjögren’s Syndrome and cutaneous lupus) as well as JDM in the CARRA Legacy Registry enrolled between 2010 and 2014 were included. Data analyzed included demographic information, disease severity, pain intensity scores, PROMIS Pain Interference scale, and Physician Global Assessment (PGA 0–10). Descriptive statistics were computed to examine pain and clinical characteristics of the cohort. Statistical comparisons between patients who reported no/mild pain versus those who reported moderate/severe pain were performed using the method of least mean squares (PROMIS Pain Interference), and to evaluate for differences in disease activity between the none/mild pain cohort and the moderate/severe pain cohort, chi-squared tests and t-tests or Wilcoxon tests were performed. Of the initial cohort of 788 patients, 711 patients were eligible for the study. Four hundred and seventy-two (66.4%) patients reported no or mild pain, and 239 (33.4%) patients reported moderate to severe pain in the last week. Those who reported moderate/severe pain had significantly greater ( p < 0.0001) scores on the PROMIS pain interference scale, had statistically higher ( p = 0.0407) mean SLEDAI scores, and statistically higher PGA ( p < 0.001) than those who reported no/mild pain in the past week. This retrospective study shows that a subset of pediatric patients (~33%) diagnosed with lupus- spectrum diseases and JDM report having moderate/severe pain in the last 7 days, and these patients experience significant pain interference compared to those who have no/mild pain.