BACKGROUND: In previous systematic reviews (predominantly of randomized controlled trials), pulmonary rehabilitation (PR) has been shown to reduce hospital admissions for acute exacerbations of COPD (AECOPD). However, findings have been less consistent for cohort studies. The goal of this study was to compare rates of hospitalized and general practice (GP)-treated AECOPD prior to and following PR. METHODS: Using anonymized data from the Clinical Practice Research Datalink and Hospital Episode Statistics, hospital admissions and GP visits for AECOPD were compared 1 year prior to and 1 year following PR in patients referred for PR. Exacerbation rates were also compared between individuals eligible and referred for PR vs those eligible and not referred. RESULTS: A total of 69,089 (64%) of the patients with COPD in the cohort were eligible for PR. Of these, only 6,436 (9.3%) were recorded as having been referred for rehabilitation. A total of 62,019 (89.8%) were not referred, and 634 (0.98%) declined referral. When combining GP and hospital exacerbations, patients who were eligible and referred for PR had a slightly higher but not statistically significant exacerbation rate (2.83 exacerbations/patient-year; 95% CI, 2.66-3.00) than those who were eligible but not referred (2.17 exacerbations/patient-year; 95% CI, 2.11-2.24). CONCLUSIONS: This study found that < 10% of patients who were eligible for PR were actually referred. Patients who were eligible and referred for (but not necessarily completed) PR did not have fewer GP visits and hospitalizations for AECOPD in the year following PR compared with those not referred or compared with the year prior to PR.