Abstract
Background: Interstitial lung diseases (ILDs) profoundly affect daily life, limiting mobility, independence, and emotional stability. While antifibrotic therapies may slow physiological decline, the living experience-characterized by breathlessness, cough, frailty, and psychological distress-remains insufficiently understood; this study therefore aimed to capture real-world patient perspectives on functional capacity, self-management, and mental health to identify treatable traits beyond conventional physiological measures. Materials and Methods: A cross-sectional quantitative online survey was conducted between September 2024 and January 2025 by Lungenfibrose e.V. in collaboration with the Center for Interstitial and Rare Lung Diseases (ZISL), Universities of Giessen and Marburg Lung Center (Giessen site). Patients with physician-confirmed ILD completed standardized instruments assessing dyspnea (MRC), cough intensity (VAS-Cough), frailty (CFS), and health-related quality of life (EQ-5D-5L). Data were analyzed descriptively across physical, functional, and psychosocial domains. Results: The majority of 69 respondents had idiopathic pulmonary fibrosis (64.7%) with a mean diagnostic delay of 1.4 ± 2.2 years; 69% were diagnosed within two years of symptom onset, and 77% were receiving antifibrotic therapy (nintedanib 57%, pirfenidone 19%). Functional limitations were substantial-55% were mobile for fewer than two hours per day, 73% reported mobility impairment, and oxygen use was common (51% during exertion, 26% at rest). Frailty increased over time (mean CFS 3.2 → 3.8), with 46% classified as fit, 36% vulnerable, and 18% frail. Dyspnea and cough remained burdensome (mean VAS-cough 40 ± 26; 58% moderate-severe), and health-related quality of life was reduced (mean EQ-VAS 56.5 ± 23.7), with high rates of anxiety/depression (78%), limitations in daily activities (76%), and pain/discomfort (74%). Despite overall satisfaction with care (mean 7.1 ± 2.5), respondents frequently reported unmet needs for psychological support and clearer communication about treatment and disease management. Conclusions: Despite antifibrotic therapy and structured specialist care, individuals living with ILD continue to face substantial physical and emotional challenges. Treatable traits-including frailty, dyspnea, inactivity, anxiety, and social isolation-emerge as key determinants of well-being. Multidisciplinary strategies integrating rehabilitation, psychosocial support, and patient education alongside pharmacological therapy are essential to preserve autonomy and improve quality of life in pulmonary fibrosis.