Background Comparative studies in SLE have shown clinico-serological differences and poorer outcomes in late-onset disease, males and patients of African and Asian descent.
Objectives To determine if there are any differences in the clinical spectrum and outcome of SLE based on age of onset, gender and ethnicity in our multi-ethnic cohort.
Methods We reviewed the records of patients with SLE seen in the Departments of Rheumatology and Nephrology from June 2003 to December 2012. We analysed the clinico-serological data and outcome, and compared the findings based on gender, age of onset and ethnicity.
Results Our 408 patients comprised 237 Indians, 137 Africans, 17 Whites and 17 Coloureds (mixed ethnicity). Patients with early-onset SLE showed a significant increase in the mean number of criteria (6.15±1.63 versus 5.25±1.25, p<0.001), discoid rash (30.2% versus 15.3%, p=0.018), nephritis (43.5% versus 15.3%, p<0.001), neuro-lupus (17.5% versus 3.4%, p=0.006), haematological criteria (76.9% versus 61%, p=0.014) and anti-dsDNA (47.9% versus 30.5%, p=0.009). Interethnic comparison between Indians and Africans showed that Indians had a longer disease duration with a median (IQR) of 75 (37-119.75) versus 42 (22-88.25) months with p<0.001, and more oral ulcers (55.7% versus 38%, p=0.001). Africans displayed a significant increase in serositis (27.7% versus 14.3%, p=0.002), nephritis (46.7% versus 35.9%, p=0.039), haemolytic anaemia (29.2% versus 19.4%, p=0.026), leucopaenia (55.5% versus 37.1%, p=0.001), and anti-dsDNA (53.3% versus 40.9%, p=0.028). Males had a higher frequency of discoid rash (47.2% versus 25.8%, p=0.006) and anti-Sm (52.8% versus 32%, p=0.016). We had 53 deaths (13%), and shorter disease duration with median (IQR) of 28 (6-115) versus 68 (35-115) months (p=0.002), serositis (32.1% versus 17.5%, p=0.038), nephritis (73.6% versus 34.1%, p<0.001), neuro-lupus (34% versus 12.4%, p<0.001), haematological abnormalities (90.6% versus 72.4%, p=0.009) and anti-dsDNA (69.8% versus 41.7%, p<0.001) were more common in the deaths. The independent predictors of death on multivariate analysis were shorter disease duration, nephritis and thrombocytopaenia. The overall 5 year-survival was 90.8% and 10 year survival was 75.1%. Although females had a higher mortality than males, there was no significant difference in the percentage of deaths based on age of onset and Indian or African ethnicity.
Conclusions Early-onset SLE is associated with more severe disease. Males have higher frequencies of discoid rash and anti-Sm antibodies, but lower mortality. Although a number of clinico-serological differences exist between Indians and Africans, they have a similar percentage of deaths. Shorter disease duration, nephritis and thrombocytopaenia were the independent predictors of death.
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Disclosure of Interest A. Budhoo: None declared, G. Mody Grant/research support from: Aaron Beare Family Chair of Rheumatology Endowment Fund for a research assistant, Consultant for: Vimovo advisory board for Astra Zeneca (South Africa) and Novartis Consumer Health Global Pain Relief Advisory Board, N. Patel Consultant for: Roche, SA; Abbvie, SA; MSD, SA, T. Dubula: None declared, P. Mody: None declared