Costs of chronic obstructive pulmonary disease in relation to compliance with guidelines: a study in the primary care setting.

BACKGROUND: The aim of this study was to analyse the economic impact of nonadherence to the Global Initiative for Obstructive Lung Disease (GOLD) guidelines in patients with chronic obstructive pulmonary disease (COPD). METHODS: A retrospective analysis was carried out on a claim database. Patients aged at least 40 years with a diagnosis of COPD were eligible for this analysis. Demographics, medical data and use of resources were collected and direct and indirect costs were analysed (from January 2008 to June 2009). A probabilistic multivariate sensitivity analysis of avoided costs was carried out. All results are presented in annualized form and costs are expressed in Euros (2009). RESULTS: A total of 1365 patients were included, 79.5% were men. The mean age (±standard deviation) was 71.4 (±10.3) years, the mean forced expiratory volume in 1 s (FEV1) was 65.3% and they had a COPD history of 5.5 (±2.9) years. Patients were divided into an adherent group and a nonadherent group depending on whether therapeutic recommendations according to severity defined in the GOLD guidelines (2007) were followed. Patients in both groups were also classified as having stage II (FEV1 < 80% and < 50%) or stage III disease (FEV1 < 50% and ≥ 30%). The total annual drug cost per patient in the nonadherent group was €771.5 while it was only €426.4 for the adherent group. The average direct cost per patient per year in the nonadherent stage II group was €1465 (±971) and it rose to €2942 (±1918) for patients in the nonadherent group with stage III disease. The potential saving from the implementation of the GOLD guidelines in stage II COPD amounted to €758 per patient per year (68% saving on drug cost). In contrast, the cost for patients with stage III disease was higher in the adherent group versus the nonadherent group (€2468). CONCLUSIONS: The cost of COPD may vary according to compliance with the GOLD guidelines. The cost observed for patients with stage II disease is higher than expected in patients who adhere to treatment, but patients with stage III disease treated according to the GOLD guidelines had significantly higher treatment costs.