Clinical features and prognostic factors of systemic sclerosis in Guangxi, China: Retrospective, single-center study of long-term survival in 470 patients.

OBJECTIVE

Systemic sclerosis (SSc) is an autoimmune disease the prevalence of which varies among populations. We analyzed SSc patients from Guangxi to improve the clinical understanding of this disease.

METHODS

Data of 470 SSc patients admitted to our institution from October 1,2012 to January 1,2019 were examined. The characteristics of these patients were analyzed using Kaplan-Meier survival analysis. Cox proportional-hazard regression was used to identify prognostic factors.

RESULTS

The average age was 50.44 ± 12.31 years, 285 patients (60.6%) were women, 2.1% had pneumoconiosis, 58.2% had pulmonary interstitial disease (ILD), 18.7% had pulmonary hypertension (PH), and 3.6% had renal crisis. These patients had diffuse cutaneous systemic sclerosis (dcSSc, 70.2%) or limited cutaneous systemic sclerosis (29.7%), and PH and renal crisis were more common in the dcSSc group. Patients 50 years old or more had greater prevalences of ILD, PH, and musculoskeletal damage, greater positivity of laboratory biomarkers, and increased mortality (all P < .05). Seventy-four patients (15.7%) died. The non-survivors were older, had longer disease duration, had higher prevalences of ILD, restrictive ventilation dysfunction, PH, and renal crisis, and had higher levels of creatine kinase myocardial band (CK-MB), C-reactive protein, and immunoglobin A (all P < .05). Renal crisis, PH, and high CK-MB were independent risk factors for death.

CONCLUSIONS

Pneumoconiosis was more common in SSc patients than the general population from this region. Our patients had a 10-year cumulative survival rate of 74.9%, higher than reported for patients from the US. Renal crisis, PH, and high CK-MB level were independent risk factors for death.