Direct medical costs of COPD--an excess cost approach based on two population-based studies

While it is known that severe COPD has substantial economic consequences, evidence on resource use and costs in mild disease is scarce. The objective of this study was to investigate excess costs of early stages of COPD.

Using data from two population-based studies in Southern Germany, current GOLD criteria were applied to pre-bronchodilator spirometry for COPD diagnosis and staging in 2255 participants aged 41 to 89. Utilization of physician visits, hospital stays and medication was compared between participants with COPD stage I, stage II+ (II or higher) and controls. Costs per year were calculated by applying national unit costs. In controlling for confounders, two-part generalized regression analyses were used to account for the skewed distribution of costs and the high proportion of subjects without costs.

Utilization in all categories was significantly higher in COPD patients than in controls. After adjusting for confounders, these differences remained present in physician visits and medication, but not in hospital days. Adjusted annual costs did not differ between stage I (€ 1830) and controls (€ 1822), but increased by about 54% to € 2812 in stage II+.

The finding that utilization and costs are considerably higher in moderate but not in mild COPD highlights the economic importance of prevention and of interventions aiming at early diagnosis and delayed disease progression.