Current status of pulmonary rehabilitation and impact on prognosis of patients with idiopathic pulmonary fibrosis in South Korea.

Background: The benefits of pulmonary rehabilitation (PR) for patients with idiopathic pulmonary fibrosis (IPF) have been limited to improving dyspnea, exercise capacity, and quality of life (QoL). This study aimed to assess the current status of PR and its effect on prognosis.

Methods: The Nationwide Korean Health Insurance Review and Assessment Service (HIRA) database was used in this study. Annual PR implementation rate since 2016 following its coverage in the health insurance was analyzed. IPF cases were defined using the International Classification of Diseases 10^th Revision (ICD-10) codes and rare intractable diseases (RID) codes. Risk of acute exacerbation (AE) and mortality of IPF patients with or without PR were analyzed.

Results: Of the 4,228 patients with IPF, only 205 (4.85%) received PR. Patients in the PR group were more frequently treated with pirfenidone and systemic steroids than non-PR group. In patients treated with steroids, mortality risk increased regardless of PR application, with hazard ratio (HR) of 1.63 [95% confidence interval (CI): 1.26-2.10, P<0.001] in the PR group and 1.38 (95% CI: 1.21-1.57, P<0.001) in the non-PR group, compared to those not treated with steroids. Additionally, PR did not significant affect mortality risk in patients not receiving steroids (HR, 1.49, 95% CI: 0.87-2.54, P=0.15). Similar patterns were seen for the risk of AE.

Conclusions: PR was applied in only a minority of patients with IPF. It did not succeed in reducing the risk of AE or mortality. A prospective study targeting early-stage patients is needed to evaluate the impact of PR considering the progressive nature of IPF disease itself.