A recent study establishes baseline estimates of the incidence and prevalence of pericarditis and myocarditis in child-onset systemic lupus erythematosus (SLE), which is substantially higher than that of adult-onset SLE. Researchers identified children (5–17 years) and adults (18–64 years) with incident SLE using US administrative claims (2000–2013). They calculated incidence and prevalence of 3 outcomes: ≥ 1 diagnosis code for 1) pericarditis and/or myocarditis, 2) endocarditis, or 3) valvular insufficiency. They found:

• There were 297 children and 6,927 adults with new-onset SLE.
• A total of 17.8% of children had ICD-9 CM codes for acute cardiac diagnoses, the incidence of which were highest in the first year after SLE diagnosis (12.2 per 100 person-years).
• African American race and nephritis were associated with acute cardiac diagnoses in children.
• Child-onset disease was independently associated with a 4.4-fold higher rate of pericarditis or myocarditis compared to adult-onset SLE after adjustment for other disease and demographic characteristics.