RESUMEN
BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal lung disease associated with dyspnoea, cough and impaired quality of life affecting around 7500 patients in Spain. OBJECTIVE: Our aim was to estimate the economic impact of IPF according to forced vital capacity (FVC) % predicted level in adult patients. METHODS: We conducted a prospective, observational, multicentric study of patients with confirmed IPF in Spain. Total annual IPF-related costs were estimated per patient, and categorised according to the FVC% predicted value (FVC < 50%, FVC 50-80%, FVC > 80%) and total sample. Incurred direct health- and non-health-related costs and indirect costs were calculated considering the IPF-related healthcare resource use and the corresponding unitarian costs. Results were updated to 2023 euros. RESULTS: Two hundred and four consecutive patients with IPF were included: 77% male, average age (standard deviation) 70.8 (7.6) years. At baseline, FVC% was < 50%, 50-80% and > 80% of predicted value in 10.8%, 74.5% and 14.7% of patients, respectively. The final cost-evaluable population included 180 subjects. The mean (standard deviation) total annual IPF-related cost was 26,997 (17,555), with statistically significant differences (p = 0.0002) between groups: 44,412 (33,389) for the FVC < 50%, 25,803 (14,688) for the FVC 50-80% and 23,242 (13,642) for the FVC > 80%. Annual direct health costs had the greatest weight and included pharmacological treatments [22,324 (13,773)] and hospitalisation days [1659 (7362)]. 14 patients had ≥ 1 acute exacerbation of IPF during the study; mean total cost of an acute exacerbation of IPF was 10,372. According to the multivariate analysis, an impaired lung function (FVC < 50%) and use of antifibrotic treatment were determinants of cost (p < 0.0001 both). CONCLUSIONS: We observed a significantly higher annual IPF-related cost at a lower level of predicted FVC%, the direct cost having the greatest weight to the total costs. Maintaining patients at early disease stages by slowing IPF progression is relevant to reduce the economic impact of IPF. CLINICAL TRIAL REGISTRATION: EU PAS register number EUPAS19387 (1 June, 2017).