Epidemiological burden of moderate-to-very severe COPD: a systematic literature review

Objective: To assess the prevalence, incidence, comorbidities, exacerbation frequency and mortality associated with moderate-to-very severe COPD across countries. Methods: A systematic literature review was conducted to identify epidemiological data in patients with moderate-to-very severe COPD (GOLD stages 2–4 [FEV1 Results: 100 studies were identified across the nine countries of interest. Differences in study populations, follow-up durations and assessment methods resulted in substantial variation in findings across studies. The weighted prevalence of COPD (GOLD 2–4) was 4.4%–8.7% across countries. Studies assessing COPD incidence were lacking. The most frequent comorbidities of COPD were cardiovascular diseases, with hypertension being the most common. The proportion of patients experiencing any COPD exacerbation ranged from 26.5%–62.3%, with rates of 0.53–2.64 events/person-year. Risk factors associated with mortality included age, male sex, BMI, comorbidities, hospital admissions and dyspnoea. Comorbidity prevalence, exacerbation frequency and mortality generally increased with the severity of COPD. Conclusions: Moderate-to-very severe COPD presents a substantial burden across countries, partly due to comorbidities, COPD exacerbations and high mortality in these patients. Additional epidemiological studies are needed to assess COPD incidence and reconcile differing methodology across studies.