Differential healthcare direct costs of asthma and chronic rhinosinusitis with nasal polyps in Catalonia (Spain).

Introduction: This study compares the direct healthcare costs associated with asthma and chronic rhinosinusitis with nasal polyps (CRSwNP) from 2013 to 2017 in Catalonia (Spain) with a population control group without these conditions.
Methods: A population administrative database containing healthcare information was used. The database contained information on primary care, hospitalisations, and emergency care from 2013 to 2017 in Catalonia. The unit cost of each healthcare procedure was imputed using a complete list of public prices for primary care services, hospital, and speciality services. Differential costs were estimated using a finite mixture model.
Results: Individuals diagnosed with asthma or CRSwNP showed a higher incidence of comorbidities than the control group. Mean annual direct costs per patient were €1,102 for asthma, €1,612 for CRSwNP and €2,197 for those with both conditions. According to our estimations, differential costs were €162 - €274 for patients with asthma and €481 - €1,257 for patients with CRSwNP compared to the reference population. These costs were significantly higher when asthma and CRSwNP coexist and especially in their severe condition.
Conclusion: This population-based study revealed that asthma and CRSwN are associated with great economic burdens for healthcare systems. These costs were significantly higher when comorbidity was present (asthma and CRSwNP) and especially in their severe condition (€4,441).