The following is a summary of “Acute effect of inhaled nitric oxide on the exercise capacity of patients with advanced interstitial lung disease: a randomized controlled trial,” published in the May 2024 issue of Pulmonology by Freidkin et al.
Inhaled nitric oxide (iNO) is a targeted therapy that selectively acts on the pulmonary vasculature of ventilated lung tissue to diminish pulmonary vascular resistance and intrapulmonary shunt. This pharmacological mechanism holds promise for mitigating ventilation/perfusion mismatch and ameliorating pulmonary hypertension among individuals grappling with interstitial lung disease (ILD).
Conducted as a prospective, single-blinded, randomized, placebo-controlled trial, this study enrolled participants with advanced ILD who underwent two distinct six-minute walk tests (6MWT): one with iNO and the other with a placebo. The primary outcome measured the disparity in meters between the distances covered in the two tests, while secondary outcomes encompassed oxygen saturation levels, distance-saturation product, and Borg dyspnea score. A predefined subgroup analysis targeted patients with pulmonary hypertension.
A total of 44 patients were scrutinized in the final analysis. Interestingly, the 6MWT distance remained akin for both iNO treatment and placebo, with median values of 362 m (IQR 265-409) and 371 m (IQR 250-407), respectively (p = 0.29). Subgroup scrutiny of patients with pulmonary hypertension unveiled no discrepancy in 6MWT distance between iNO and placebo, manifesting median values of 339 (256-402) and 332 (238-403) meters for the iNO and placebo tests, respectively (P=0.50). Intriguingly, no discernible correlation emerged between mean pulmonary artery pressure values and the alteration in 6MWT distance between iNO and placebo (Spearman correlation Coefficient 0.24, P=0.33).
In patients grappling with advanced ILD, regardless of the presence of concurrent pulmonary hypertension, the administration of inhaled nitric oxide did not yield discernible improvements in six-minute walk distance or oxygen saturation levels. Nonetheless, the utilization of inhaled NO proved to be safe, devoid of any noteworthy adverse effects.
Source: bmcpulmmed.biomedcentral.com/articles/10.1186/s12890-024-03051-4