Objective: Socioeconomic differences in quality of care have been suggested to contribute to inequality in clinical prognosis of COPD. We examined socioeconomic differences in the quality of COPD outpatient care and the potential of a systematic quality improvement initiative in reducing potential socioeconomic differences.

Methods: A mandatory national quality improvement initiative has since 2008 monitored the quality of COPD care at all national pulmonary specialized outpatient clinics in Denmark using six evidence-based process performance measures. We followed patients aged ≥30 years with a first-ever outpatient contact for COPD during 2008–2012 (N = 23,741). Adjusted year-specific relative risks (RR) of fulfilling all relevant process performance measures was compared according to ethnicity, education, income, employment, and cohabitation using Poisson regression.

Results: Quality of care improved following the implementation of the clinical improvement initiative with 11% of COPD patients receiving optimal care in 2008 compared to 57% in 2012. Substantial socioeconomic differences were observed the first year: immigrants (RR 0.41, 95% CI 0.21–0.82), the unemployed (RR 0.37, 95% CI 0.18–0.74), disability pensioners (RR 0.63, 95% CI 0.46–0.87) and patients living alone (RR 0.80, 95% CI 0.60–0.97) were less likely to receive all relevant care processes, whereas those with highest education (RR 1.22, 95% CI 0.92–1.63) were more likely to receive these processes. These differences were eliminated during the study period.

Conclusion: A systematic quality improvement initiative including regular audits, knowledge sharing, and detailed disease-specific recommendations for care improvement may increase the overall quality of care and considerably modify the substantial socioeconomic inequalities in COPD management.