Burden of Disease and Productivity Loss in the European Economic Area in Patients Affected by Fibrosing Interstitial Lung Disease

Abstract

Introduction: Progression of fibrosis in interstitial lung diseases (ILD) has been associated with poor prognosis, lower quality of life for patients and caregivers, and higher healthcare costs. This study estimated the burden of disease and productivity loss of progressively fibrosing ILD, focusing on progressive pulmonary fibrosis other than idiopathic pulmonary fibrosis (non-IPF PPF) and systemic sclerosis-associated ILD (SSc-ILD) in the European Economic Area (EEA).

Methods: An economic model was built to estimate the clinical burden of SSc-ILD and non-IPF PPF. The model was based on published data on disease prevalence and disease burden (in terms of comorbidities, exacerbations, and deaths) as well as on productivity loss (in terms of sick days, early retirement, permanent disability, and job loss). Aggregate income loss was obtained by multiplying productivity loss by the median daily income in each country/area of investigation. A sensitivity analysis was performed to test the impact of the variability of the model assumptions.

Results: In the whole EEA, a total of 86,794 and 13,221 individuals were estimated to be affected by non-IPF PPF and SSc-ILD, respectively. Estimated annual sick days associated with the diseases were 3,952,604 and 672,172, early retirements were 23,174 and 5341, permanently disabled patients were 41,748 and 4037, and job losses were 19,789 and 2617 for non-IPF PPF and SSc-ILD, respectively. Annual exacerbations were estimated to be 22,401-31,181 and 1259-1753, while deaths were 5791-6171 and 572-638 in non-IPF PPF and SSc-ILD, respectively. The estimated annual aggregate income loss in EEA, accounting for losses due to annual sick days, early retirements, and permanently disabled patients, was €1433 million and €220 million in non-IPF PPF and SSc-ILD, respectively. The productivity loss due to job losses was €194 million and €26 million in non-IPF PPF and SSc-ILD, respectively. The main driver of aggregate income loss variability was the prevalence.

Conclusion: The impact of non-IPF PPF and SSc-ILD on society is definitely non-negligible. Actions to reduce the burden on our societies are highly needed.

Keywords: Disease burden; Income loss; Indirect costs; Productivity loss; Progressive fibrosing interstitial lung disease; Systemic sclerosis.