Causes and predictors of death in South Africans with systemic lupus erythematosus

Little is known about the long-term outcome and mortality patterns in systemic lupus erythematosus (SLE) in sub-Saharan Africa. We undertook a retrospective study of SLE in mainly black, unemployed patients, seen at a tertiary institution in Soweto, South Africa, to determine the causes and predictors of death.

Demographic, clinical and laboratory data and outcome were extracted from the case records of patients attending the Lupus Clinic at Chris Hani Baragwanath Hospital.

Of the 270 case records with a diagnosis of SLE, 226 met the American College of Rheumatology classification criteria for SLE. The female to male ratio was 18 : 1. The mean (s.d.) age at presentation was 34 (12.5) yrs. Arthritis, nephritis and neuropsychiatric disease had a cumulative frequency of 70.4, 43.8 and 15.9% of patients, respectively. During the course of a mean follow-up period of 54.9 months, 193 (85.3%) and 89 (39.3%) patients were treated with oral corticosteroids and immunosuppressive agents, respectively. There were 55 (24.5%) known deaths and 64 (28.6%) patients were lost to follow-up. The estimated 5 yr survival rates were between 57 and 72%, depending on whether the group of patients lost to follow-up was classified in the analysis as either alive or dead. Infection (32.7%) was the commonest cause of death followed by renal failure (16.4%). Univariate analysis revealed that nephritis, neuropsychiatric disease and hypocomplementaemia were associated with an increased mortality, but multivariate analysis showed nephritis as the only significant predictor of mortality.

Our findings suggest that SLE in indigent South Africans not only carries a poorer prognosis but also the main cause of death, infection and renal failure differ from those reported recently in industrialized Western countries. Nephritis is common in our patients and is the only independent predictor of poor outcome.