Predictors of morbidity and mortality in early systemic sclerosis: Long-term follow-up data from a single-centre inception cohort

Abstract

Objectives: To determine predictors of morbidity and mortality in systemic sclerosis (SSc) in a long-term follow-up of an inception cohort of early SSc patients.

Methods: We evaluated clinical manifestations, laboratory and lung function tests at disease onset as predictors of morbidity and mortality in 3rd, 6th and 9th year in SSc patients recruited within 12 months of disease onset.

Results: A total of 115 SSc patients (97 women, mean age 48.1 ± 13.5 years, 54 diffuse subtype) were included. In multivariate regression analysis, predictors at disease onset for the presence of pulmonary fibrosis in 6th year of follow-up were diffuse subtype (OR: 4.4, p = 0.033), digital ulcers (OR: 7.9, p = 0.014) and esophageal involvement (OR: 4.79, p = 0.038). Arrythmias at disease onset predicted pulmonary hypertension (OR: 6.05, p = 0.022), while age (OR: 1.12, p = 0.002) and anti-Scl70 (OR: 4.3, p = 0.038) predicted arrhythmias in 6th year. During a follow-up of 101.8 ± 48.5 months, 23/115 patients died. Cox proportional hazard models analysis revealed 6 independent predictors of mortality present at disease onset: age at disease onset (45-59 years (HR: 3.0, p = 0.098), ≥60 years (HR: 4.3, p = 0.073), male gender (HR: 3.63, p = 0.025), diffuse subtype (HR: 2.83, p = 0.095), pulmonary fibrosis (HR: 3.7, p = 0.032), echocardiography-diagnosed pulmonary hypertension (HR = 7.49, p = 0.008) and DLCO < 60% (HR: 3.17, p = 0.035). Mortality rates at 3 and 6 years were 14% and 24% for patients with 3 independent predictors and 46% and 53% for patients with 4-6 predictors, respectively.

Conclusion: Clinical phenotypes at disease onset may predict morbidity and mortality in SSc and guide treatment decisions.

Keywords: Inception cohort; Morbidity; Mortality; Predictors; Systemic sclerosis.