DETECT Study Identifies Risk Factors for PAH Progression in SSc-PAH Patients

Male gender and certain lung function parameters are potential risk factors for the progression of pulmonary arterial hypertension in patients with systemic sclerosis-PAH (SSc-PAH), an analysis of the DETECT study shows.

The research, “Factors associated with disease progression in early-diagnosed pulmonary arterial hypertension associated with systemic sclerosis: longitudinal data from the DETECT cohort,” was published in the journal Annals of the Rheumatic Diseases.

PAH is known to be a severe complication of SSc and is associated with high mortality rates in patients who are not diagnosed and treated in a timely manner. In order to make a correct diagnosis of PAH, right-side heart catheterization (RHC) is the gold standard in medical practice.

In the multicenter DETECT study (NCT00706082), researchers used RHC in SSc patients to determine which patients were at risk of developing PAH. They also developed a computer-based algorithm to determine which SSC patients had a higher risk of developing PAH.

The analysis allowed researchers to identify from early on the SSc patients with mild PAH. Currently unknown, however, are the risk factors associated with disease progression in these early-diagnosed patients.

To identify these risks, researchers followed patients in the DETECT study for up to three years. They analyzed 21 parameters and whether there was a correlation with disease progression, which was determined by a physician according to at least one of the following events: WHO Functional Class (FC) worsening, initiation of combination therapy for PAH, hospitalization, or death.

Results showed that out of 57 patients with PAH, 25 had progressive PAH. Four patients died, 11 were hospitalized for PAH, 14 had at least one occurrence of WHO FC worsening, and eight received PAH-specific combination treatment.

When analyzing the specific parameters associated with disease progression, researchers found that being a male was associated with 4.1 times higher risk of disease progression. Furthermore, patients with low diffusing capacity of the lung for carbon monoxide (DCLO), and a high ratio of forced vital capacity (FVC) to DLCO — measures of pulmonary function — had 3.6 times higher risk of disease progression. Patients with high Borg Dyspnoea index, a measure of shortness of breath in response to exercise, had 1.7 times higher risk of disease progression.

Overall, “the results of our study have practical implications, as they show that patients with early SSc-PAH have a meaningful rate of disease progression over a relatively short time, requiring a close follow-up,” researchers concluded.