Reduced 6-minute walk distance (6MWD) in sarcoidosis-associated pulmonary hypertension (SAPH) is influenced by multiple factors — although not all factors are predictive of a reduced 6MWD measurement, according to research presented at the American Thoracic Society (ATS) 2017 International Conference, held May 19-24 in Washington, DC.
Researchers obtained data from the Registry for Sarcoidosis Associated Pulmonary Hypertension (ReSAPH) — a multinational registry of 220 patients with SAPH — to assess patients’ 6MWD.
In total, data from 150 patients included 6MWD. The researchers found a significant correlation between 6MWD and predicted forced vital capacity (FVC; rho=0.195; P =.0165) or 6MWD and predicted diffusing capacity of the lung for carbon monoxide (DLCO; rho=0.412; P <.0001).
A negative correlation was noted between 6MWD and mean pulmonary artery pressure, pulmonary vascular resistance, and both systolic and diastolic pulmonary artery pressure (rho=0.285, 0.289, 0.352, and 0.228, respectively; P =.0004, P =.007, P <.0001, and P =.0050, respectively). No correlation existed between 6MWD and right atrial pressure or cardiac output.
Using multi-regression analysis, researchers found that DLCO percentage and systolic pulmonary artery pressure were the only “significant independent variable[s] associated with 6MWD,” (P =.0033 and .0343, respectively).
“For patients with SAPH, the 6MWD is influenced by several factors, including lung tissue volume [and] changes in lung vasculature,” the researchers concluded. “The DLCO was the best determinant of the 6MWD, and changes in DLCO may be more important than other pulmonary function test measurements.”
Disclosures: This study was supported by Gilead.
Alhamad EH, Scholand MB, Kouranos V, et al. Determinants of six minute walk distance in sarcoidosis associated pulmonary hypertension. Presented at: American Thoracic Society (ATS) 2017 International Conference; Washington, DC; May 19-24. Poster A4753.