PAH Confirmed as Major Cause of Death in Scleroderma Patients, Researchers Say

Pulmonary arterial hypertension (PAH) represents a major cause of mortality in patients with scleroderma, or systemic sclerosis, accounting for 52% of all deaths — mainly within the first few years after PAH diagnosis, according to recent findings.

The fact that PAH is a leading cause of death in scleroderma patients has been known among medical researchers. Now, results from the Pulmonary Hypertension Assessment and Recognition of Outcomes in Scleroderma (PHAROS) registry confirm this trend.

The findings were reported in an article titled, “Long-term outcomes in systemic sclerosis associated pulmonary arterial hypertension from the pulmonary hypertension assessment and recognition of outcomes in scleroderma registry (PHAROS),” published in the journal Chest.

PHAROS is a registry of scleroderma patients who have, or are at high risk of, PAH based on right heart catheterization — a method routinely used to diagnose PAH. Nineteen centers were part of the registry.

In this prospective study, researchers investigatied long-term outcomes in patients with scleroderma-associated PAH (scleroderma-PAH).

The study enrolled 160 incident scleroderma-PAH patients, who were followed for eight years.

Scleroderma-PAH patient survival rates at one, three, five, and eight years were 95%, 75%, 63% and 49%, respectively. Within this group, PAH accounted for 52% of all deaths.

When the team restricted the number of deaths to the ones caused by PAH, the survival rates were 97% after one year; 83% after three years; and 76% after both five and eight years.

These numbers represent higher survival rates compared to scleroderma-PAH nonrelated deaths.

Importantly, the research team found that 93% of the PAH-related deaths occurred within four years of the PAH diagnosis.

Different factors were found to impact the survival rate of these patients, including patient gender — with males being more susceptible to the disease — diffuse scleroderma, elevated pulmonary blood pressure, lower exercise capacity, and lower diffusing capacity of the lungs for carbon monoxide (DLCO; a medical test used to measure lung disease severity).

The effect of medication on patients’ survival was also assessed, but no differences were detected in this study.

A previous analysis of PHAROS data showed that short-term predictors of mortality in scleroderma-PAH patients included ages older than 60, male gender, reduced exercise capacity, and DLCO under 39%.

Now researchers found that in the long-term, only male gender and DLCO remained as predictors of death in scleroderma-PAH patients.

“Overall survival in PHAROS was higher than other scleroderma-PAH cohorts,” researchers wrote. “PAH accounted for more than half of deaths and primarily within the first few years after PAH diagnosis.”

“Optimization of treatment for those at greatest risk of early PAH-related death is crucial,” they emphasized.