OBJECTIVES: To estimate 6 months costs and quality of life (QoL) of patients with moderate to very severe COPD (GOLD criteria) who experienced a COPD exacerbation in comparison with control groups of similar COPD severity without exacerbation. METHODS: COPD in- and outpatients (Grade II=28; III=31; IV=31) with exacerbation (EXA-groups) were assessed retrospectively (3 month prior to exacerbation) and prospectively (3 month after exacerbation) and compared to controls (CO-groups) of similar disease severity but stable health (3 month retrospective assessment). Direct costs included hospitalization, outpatient visits, laboratory tests, imaging, medication and rehabilitation. Indirect costs included short and long term disability payments. All costs were converted to a period of 180 days; health care costs used 2008 prices from the payer´s perspective. A validated translation of the EQ5D was completed at inclusion day (all groups) and at final visit (EXA-groups). RESULTS: About 18% of grade-II and 75% grade-IV exacerbations were hospitalized, resulting in increased costs with COPD severity (6-months median: Grade II=€846; III=€2159; IV=€3856; all p<0.05). Median 6-months costs in CO-groups were lower, although increasing from moderate to very severe COPD (Grade II=€567; III=€1610; IV=€2084; all p<0.05). Exacerbation accounted for 8% (grade-II) to 31% (grade-IV) of total 6-months costs. Mean EQ5D utilities in the CO-groups and in the EXA-groups at final visit were comparable (moderate: 0.589 vs.0.636; severe: 0.623 vs. 0.591; very severe: 0.524 vs. 0.479; NS). Mean EXA-groups utilities at inclusion were significantly lower compared to final assessment (p<0.001) and decreasing with COPD severity (moderate: 0.524; severe: 0.390; very severe: 0.230), reflecting QoL impairment during COPD exacerbation and natural disease course.  CONCLUSIONS: The BURDEN study confirmed for the Czech Republic a considerable economic burden of COPD. In accordance with international literature we found increased costs and decreased QoL for 1) COPD exacerbation vs. control in stable state, and 2) COPD progression.