The SAPHIRE trial linked rheumatoid arthritis (RA) to a higher prevalence of elevated echocardiography-derived pulmonary artery pressure.
“Patients with RA may therefore represent another population for whom PAH screening with noninvasive tools such as EchoCG may be justified,” the authors wrote.
According to the paper, it has been suggested that pulmonary arterial hypertension (PAH) is an autoimmune disease due to the association between PAH and scleroderma, systemic lupus erythematosus, and Sjögren’s syndrome. However, there is inconclusive data to tie RA to a higher risk of PAH.
Dr G. E. M. Reeves, MBBS at John Hunter Hospital at the University of Newcastle in Callaghan, Australia and colleagues sought to understand the prevalence of PAH in patients with RA in the Stress Associated Pulmonary Hypertension in Rheumatoid Evaluation (SAPHIRE) study. Their results were published in the International Journal of Rheumatology.
The investigators invited 177 patients with RA according to the American College of Rheumatology Criteria to undergo testing that included a World Health Organization (WHO) functional class assessment, a 6 minute walk test, pulmonary function testing with carbon dioxide diffusing capacity (DLCO), exercise Doppler echocardiography to estimate peak systolic pulmonary artery pressure (PASP), and right heart catheterization for direct pulmonary artery measurements.
Data was obtained on 80 patients with RA, with most diagnoses of PAH from echocardiographic measurements due to participant hesitancy to have invasive testing. Only 6 participants underwent right heart catheterization with 2 participants receiving a PAH diagnosis. PASP by echocardiography was significantly higher in patients with PAH compared to patients without PAH (PASP at rest: 40.8 mm Hg vs 25.5 mm Hg, P<.05; PASP with exercise 42.5 mm Hg vs 28.2 mm Hg, P<.05). Further, patients with echocardiographically-derived elevation of pulmonary pressure (EDEPP) had significantly reduced 6 minute walk distance (356.8 vs 441.3 m, P<.05) and DLCO (78.8 vs 85.3% of predicted, P=.004).
Based on the defined resting PASP cutoff of > 35 mm Hg used in this study, the investigators estimated the prevalence of PAH was 14% in patients with RA.
Early detection of PAH in high risk patients is important because of the insidious nature, poor survival, and now therapeutic options for PAH. Further, improved survival has been tied to pulmonary hypertension screening.
Summary & Clinical Applicability
The authors highlighted that although right heart catheterization is the “gold standard test” to diagnose PAH, it is impractical for screening in high-risk populations.
The results of the study suggest that, along with other autoimmune diseases, patients with RA may have an increased prevalence of PAH and require assessments for PAH. However, because the data was mostly obtained through indirect methods, confirmation studies are needed, the authors wrote.
Limitations & Disclosures
The study was funded by GlaxoSmithKline. The authors report no competing interests.
Reeves GE, Collins N, Hayes P, et al. SAPHIRE: Stress and Pulmonary Hypertension in Rheumatoid Evaluation-A Prevalence Study. Int J Rheumatol. 2016;2016:4564531.