Pulmonary Vasodilator Treatment May Lower Hospitalization Risk From SAPH

Newly published data from a retrospective study suggest that inhaled vasodilators could reduce the risk of hospitalization among patients with sarcoidosis‐associated pulmonary hypertension (SAPH).

These insights represent the first characterization of risk factors for respiratory failure–related hospitalization among patients with SAPH. To date, other studies have documented risk factors among patients with sarcoidosis and patients with PH, although not patients with both conditions.

If the benefit of pulmonary vasodilator therapy is confirmed in further research, the finding could offer guidance for management of PH in patients with SAPH, a condition that has a lack of clear guidelines and recommendations.

“Anywhere from 5.7% to 28.3% of patients with sarcoidosis develop SAPH,” explained the researchers in Pulmonary Circulation. “SAPH occurs more so within fibrotic sarcoidosis, but it can occur even in the absence of significant lung disease. PH confers increased morbidity and mortality among patients with sarcoidosis. Almost 74% of patients with sarcoidosis are referred for lung transplantation have SAPH.”

All 58 patients included in the study underwent lung transplant evaluation at a single center between 2008 and 2021, and two-thirds of these patients were hospitalized at some point before lung transplantation or death.

Among the patients, pulmonary vasodilator therapy had the strongest association with a reduced hospitalization risk, with a 77% reduced risk seen in a multivariate analysis. Two-thirds of patients were receiving such therapy. Other treatments used by patients in the study included phosphodiesterase‐5 inhibitors, endothelin-receptor antagonists, inhaled prostacyclin, and subcutaneous prostacyclin.

The same analysis showed a 4% decrease of hospitalization associated with every 1% increase in percent-predicted forced expiratory volume in 1 second (FEV₁). The researchers noted that the clinical significance of the association between this calculation and risk of hospitalization is unclear, as better lung function resulting in decreased risk of hospitalization should also show a similar association with forced vital capacity (FVC).

At the time of PH diagnosis, the mean (SD) FEV₁ was 1.26 (0.52) L, the mean percent‐predicted FEV₁ was 47.1% (16.5%), the mean FVC was 1.82 (0.68) L, and the mean percent‐predicted FVC was 53.5% (15.4%). By 12 months into the study, FEV₁ had decreased by 79.7 (22.4) mL and FVC by 87.8 (33.3) mL.

The group found that previously documented risk factors—being female, receiving anti-inflammatory treatment, race, or comorbidities—in patients with sarcoidosis did not increase the risk of respiratory failure–related hospitalization in their cohort of patients with SAPH.

Fifty-three percent of patients were women and 79% were Black. Comorbidities included extrapulmonary sarcoidosis (24%), diabetes (22%), concomitant chronic obstructive pulmonary disease (40%), chronic kidney disease (53%), liver disease attributed to hepatic sarcoidosis (11%), and heart disease (81%).

“Given this, it may be possible that hospitalization risk among those with SAPH is driven by PH risk factors,” noted the researchers. “N‐terminal pro‐brain natriuretic peptide, anemia, and renal dysfunction have been identified as independent predictors of 2‐year hospitalization in patients with Group 1 pulmonary arterial hypertension (PAH). Therapy with certain vasodilators has been found to improve morbidity in patients with PAH, including reducing hospitalizations.”

The effect of certain pulmonary vasodilators seen previously in patient with PAH is similar to that seen among the patients with SAPH in the current study, although there was no effect of renal dysfunction or B‐type natriuretic peptide on hospitalization in the current cohort.

These findings from the subset of patients, cautioned the researchers, may not be generalizable to other patients, including those with less severe lung disease or those not eligible for lung transplant evaluation due to factors like significant comorbid conditions.

Reference

Gayen S, Mamary A. Predictors of hospitalization for respiratory failure among patients with sarcoidosis‐associated pulmonary hypertension. Pulm Circ. Published online March 25, 2023. doi:10.1002/pul2.12212