Economic valuation and determinants of informal care to disabled people with Chronic Obstructive Pulmonary Disease (COPD)

Background: We aimed to estimate the monetary value of informal care of disabled people with chronic obstructive pulmonary disease (COPD) in Spain and to identify the main determinants of the time involved in informal caregiving. Methods: We used the Survey on Disabilities, Autonomy and Dependency carried out in Spain in 2008 to obtain information on disabled individuals with COPD and their informal caregivers. Assessment of informal caregiving time was performed using the proxy good method. A statistical multivariate analysis (ordered probit model) was performed to study the determinants of informal care provided. Results: It was estimated that 220,892 disabled people with COPD received informal care. The total annual number of caregiving hours was 694.44 million, with an estimated monetary value between 4,981 and 8,254 million EUR. Based on the condition of having received informal care, the cost of informal care per disabled person with COPD ranged from 24,549 to 40,681 EUR per year (depending on the shadow price applied). This value varies significantly depending on the degree of dependency; it ranged from 17,089 EUR per person annually for non-dependents to 33,033 EUR for those who were greatly dependent (under the most conservative scenario). Degree of dependency and the formal care received were the main variables that explained the variability of informal caregiving time provided. Conclusions: The results partially reveal the high hidden social costs, and the association between the level of dependency and the time provided by the caregivers. This information should be a useful tool to design policies that focus on improving caregivers' well-being.