Causes and predictors of mortality in South Africans with systemic sclerosis

BackgroundThere is a dearth of mortality data on systemic sclerosis (SSc) in sub-Saharan Africa. We undertook a retrospective study of causes and predictors of death in low-income indigent South Africans with SSc. MethodsA retrospective records review of clinicodemographic, laboratory, and outcome data of SSc patients attending a state-funded tertiary Rheumatology service in South Africa. ResultsMost of the 164 patients were Black (92.7%) and female (87.8%). The mean (SD) age at diagnosis and follow-up duration were 42.6 (12.9) and 5.5 (5.6) years, respectively. The majority (75.6%) had diffuse cutaneous SSc (dcSSc); and digital pits/ulcers, interstitial lung disease (ILD), and pulmonary hypertension (PH) were documented in 73.6%, 55.0%, and 38.3%, respectively. There were 56 known deaths and an equal number of patients were lost to follow-up. Deaths resulted from ILD complicated by PH (42.9%), infections (8.9%), cardiac disease (7.1%), and malignancies (3.6%). Estimated 5- and 10-year survival rates for patients with known outcomes were 58% and 42%, respectively. Independent predictors of death were renal dysfunction and cor pulmonale. ConclusionMost patients in this study of South Africans had dcSSc and poor outcomes. Known deaths resulted from cardiorespiratory complications of ILD complicated by PH. Cor pulmonale and renal dysfunction were independent predictors of death.