Survival in scleroderma: results from the population-based South Australian Register

Abstract

Aim: To ascertain the mortality risk and investigate clinical and serological factors influencing survival of patients listed on the South Australian Scleroderma Register (SASR).

Methods: The SASR is a population-based register, which was commenced in 1993 and has actively sought to recruit all scleroderma patients diagnosed in SA over a 15-year period. Clinical and serological details have been accessed from questionnaires or from clinical and laboratory files. Standardized mortality ratio (SMR) was calculated and survival analyses performed on all living and deceased patients listed on this SASR (n = 786).

Results: Patients with scleroderma had increased mortality compared with the general SA population (SMR 1.46 (95% confidence interval (CI) 1.28-1.69)). Factors that adversely altered survival included older age at onset, male gender, diffuse skin involvement, presence of scleroderma renal crisis, pulmonary fibrosis, pulmonary arterial hypertension, cancer and anti-topoisomerase (Scl-70) and anti-U1 RNP antibodies, while a trend was observed with increased nailfold capillary dropout. Mean age of death for patients with limited scleroderma was 74.1 years (95% CI 72.5-75.7), diffuse scleroderma 62.9 years (95% CI 59.4-66.4) and overlap disease 57.8 years (95% CI 48.7-66.9). Survival improved over the 15-year study period.

Conclusions: Scleroderma substantially reduces life expectancy. Survival is influenced by age at onset, gender, diffuse involvement of skin fibrosis, visceral involvement, development of cancer, extent of microvascular capillary damage and by the presence of scleroderma-associated antibodies, Scl-70 and RNP. Scleroderma renal crisis continues to carry high mortality. Survival improved over the 15-year study period.