OBJECTIVES: To estimate COPD exacerbation incidence rates, related costs, and predictors among managed care patients treated for chronic bronchitis (CB). METHODS: A retrospective analysis of the HealthCore Integrated Research Database (HIRD) was conducted to estimate the incidence, costs, and predictors of COPD exacerbations. The study population included CB patients aged ≥40 years with ≥2 years of continuous enrollment in the HIRD, ≥1 hospitalization/emergency department (ED) visit or ≥2 outpatient visits with CB diagnosis (ICD-9-CM 491.xx) from January 1, 2004 to May 31, 2011, and ≥2 pharmacy fills for COPD medications during the follow-up year (the first fill served as the index date). Patients with asthma, cystic fibrosis, respiratory tract cancer, and long-term oral corticosteroid use were excluded. COPD exacerbations were categorized as severe (hospitalization with COPD as primary diagnosis) or moderate (ED visit with a primary COPD diagnosis or an oral corticosteroid filled within 7 days of a COPD-related office visit). When multiple exacerbations occurred within a 14-day window, only one (the most severe, if applicable) was counted. Prevalence, costs, and predictors of exacerbations were measured. RESULTS: A total of 17,382 treated CB patients met inclusion/exclusion criteria (50.6% female, mean age 66.7±11.4 years). During pre-index year, 25% had moderate or severe and 14.3% had severe exacerbations. During the post-index year, the mean COPD maintenance medication fills number was 7.6±6.3; 42.6% experienced moderate or severe and 24.7% experienced severe exacerbations. Mean exacerbation-related healthcare costs were $8,219±$22,644 per moderate or severe and $18,120±$31,592 per severe exacerbation. Incidence of baseline exacerbation was the best predictor of post-index incidence of exacerbation (β=0.2595, p<0.0001) and also predicted post-index exacerbation-related costs (β=0.0870, p<0.0002). CONCLUSIONS: CB individuals’ exacerbation rates remain high despite treatment with COPD maintenance medications.  New treatment strategies designed to reduce CB exacerbations and associated costs should focus on patients with high prior-year exacerbation rates.