COPD exacerbations by disease severity in England

Objectives: Exacerbations of chronic obstructive pulmonary disease (COPD) are associated with accelerated disease progression and are important drivers of health care resource utilization. The study aimed to quantify the rates of COPD exacerbations in England and assess health care resource utilization by severity categories according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2013.

Methods: Data from the Clinical Practice Research Datalink linked to Hospital Episode Statistics were used to identify patients with a COPD diagnosis aged ≥40 years. Those with complete spirometric, modified Medical Research Council Dyspnea Scale information, and exacerbation history 12 months prior to January 1, 2011 (index date) were classified into GOLD severity groups. Study outcomes over follow-up (up to December 31, 2013) were exacerbation rates and resource utilization (general practitioner visits, hospital admissions).

Results: From the 44,201 patients in the study cohort, 83.5% were classified into severity levels GOLD A: 33.8%, GOLD B: 21.0%, GOLD C: 18.1%, and GOLD D: 27.0%. Mean age at diagnosis was 66 years and 52.0% were male. Annual exacerbation rates per person-year increased with severity, from 0.83 (95% confidence interval [CI]: 0.81-0.85) for GOLD A to 2.51 (95% CI: 2.47-2.55) for GOLD D. General practitioner visit rates per person-year also increased with severity, from 4.82 (95% CI: 4.74-4.93) for GOLD A to 7.44 (95% CI: 7.31-7.61) for GOLD D. COPD-related hospitalization rates per person-year increased from less symptoms (GOLD A: 0.28, GOLD C: 0.39) to more symptoms (GOLD B: 0.52, GOLD D: 0.84).

Conclusion: Patients in the most severe category (GOLD D) experienced nearly three times the number of exacerbations and COPD-related hospitalizations as those in the least severe category (GOLD A), in addition to increased general practitioner visits. Better patient management to stabilize the disease progression could allow for an improvement in exacerbation frequency and a reduction in health care resource utilization.