Prevalence of distress and changes over time among patients with progressive fibrosing interstitial lung disease

Abstract Background Patients with progressive fibrosing interstitial lung disease (PF-ILD) frequently experience respiratory symptoms and decline in activities of daily living (ADL) and quality of life (QOL) with disease progression. However, no effective treatment or palliative care strategy has been established for patients with PF-ILD. This study aimed to clarify the degree of physical and psychological distress in patients with PF-ILD and to evaluate symptom changes over a one-year period in patients with idiopathic pulmonary fibrosis (IPF) and those with other PF-ILDs (non-IPF). Methods Consecutive patients diagnosed with PF-ILD were recruited. The participants were divided into two groups and evaluated at registration (T0), 26 weeks (T1), and 52 weeks (T2) after registration. They were also followed-up for symptoms, ADL, QOL, depressive condition, laboratory findings, and other factors from study registration to 52 weeks (T2). Results Of the 70 patients with PF-ILD, 32 had IPF and 38 did not. The IPF and non-IPF groups showed no noticeable differences in clinical symptoms or laboratory findings on multivariate analysis at T0. The repeated-measures analysis of variance used to observe the changes over the course of the year in both groups showed that dyspnea in patients with IPF worsened from T1 to T2. In contrast, cough, which is one of the major symptoms in non-IPF patients, worsened, especially from T0 to T1 and T0 to T2. The QOL of non-IPF patients also declined from T0 to T1. Conclusions Patients with PF-ILD demonstrated several clinical signs and symptoms. In this one-year follow-up study, dyspnea tended to be worse in patients with IPF and cough in non-IPF patients, and QOL was temporarily worse in non-IPF patients. Respiratory symptoms are directly related to the patient's daily life and led to reduced QOL. Therefore, further long-term studies in this population are required.