To determine the influence of ethnicity and sociodemographic factors on disease characteristics of the Canadian Pediatric Lupus population.
Childhood-onset SLE (cSLE) patients at four pediatric centers in Halifax, Montreal, Toronto and Vancouver were consecutively recruited. Sociodemographics and disease data were collected. Patients were categorized by their primary self-selected ethnicity, and exploratory cluster analyses were examined for disease expression by ethnicity.
We enrolled 213 cSLE patients, and ethnicity data were available for 206 patients: White (31%), Asian (30%), South Asian (15%), Black (10%), Latino/Hispanic (4%), Aboriginal (4%) and Arab/Middle Eastern (3%). The frequency of clinical classification criteria (malar rash, arthritis, serositis and renal disease) and autoantibodies significantly differed among ethnicities. Medications were prescribed equally across ethnicities: 76% were taking prednisone, 86% anti-malarials, and 56% required additional immunosuppressants. Cluster analysis partitioned three main groups – mild (N = 50), moderate (N = 82) and severe (N = 68) disease clusters. Only 20% of White patients were in the severe cluster compared to 51% of Asian and 41% of Black patients (p=0.03). However, disease activity indices and damage scores were similar across ethnicities.
Canadian cSLE patients reflect our multi-ethnic population, with differences in disease manifestations, autoantibody profiles and severity of disease expression by ethnicity.