Clinical characteristics and mortality rate of Thai elderly-onset systemic sclerosis

To identify the clinical differences and mortality rate between adult and elderly onset systemic sclerosis (SSc).

We conducted a historical cohort study of SSc patients during January 2007-December 2011. The SSc patients were 60 and over classified as elderly onset SSc. Cox regression analysis was used to estimate the probability of survival and for assessing the factors associated with mortality.

The medical records of 350 SSc patients were reviewed; 53 (15.1%) had elderly onset SSc. According to the multivariate analysis, elderly onset SSc has a higher WHO functional class, more frequent weakness, more frequent hyperCKaemia, and less pulmonary fibrosis than adult onset SSc (p=0.004, 0.02, 0.02, 0.02, respectively). The incidence of mortality was 3.8 per 100 person-year with a median survival rate of 15.9 years (95%CI 12.4-17.3). The mortality rate of elderly SSc onset was significantly higher than that of adult SSc onset (HR 5.71; 95%CI 3.54-9.20). The median survival of elderly and adult onset SSc was 4.9 years and 16.1 years, respectively. The Cox regression analysis indicated that presence of digital ulcer and tendon friction rub had a respective HR of 7.39 (95%CI 1.28-42.60) and 37.23 (95%CI 2.10-659.09) for predicting mortality of elderly onset SSc.

Myopathy and limitation of physical activity were frequently found among elderly onset SSc over against pulmonary involvement than in adult onset SSc. Mortality of elderly onset SSc was 5.7 times higher, and median survival was 11 years shorter, than adult onset SSc.