Published: 19 April 2022
Authors: Yunus Çolak, Børge G. Nordestgaard, Peter Lange, Jørgen Vestbo, and Shoaib Afzal
Source: This abstract has been sourced from NZ Respiratory Research Review Issue 204
Rationale: Randomized controlled trials only include a subset of patients with chronic obstructive pulmonary disease (COPD) fulfilling strict inclusion criteria. Thus, most patients with COPD in a real-world setting do not have the necessary evidence to support treatment effectiveness.
Objectives: To test the hypotheses that most individuals with COPD in the general population are not represented in major clinical trials despite clinically significant disease with exacerbations and early death.
Methods: In 105,630 adults from a Danish contemporary population-based cohort, we defined COPD as age 40 or more years, chronic respiratory symptoms, history of smoking exposure, and airflow limitation with FEV1/FVC < 0.70. Outcomes included acute exacerbations and all-cause mortality. Symptomatic smokers without COPD were used as a reference group.
Measurements and Main Results: Of all, 7,516 (7%) and 16,079 (15%) were symptomatic smokers with and without COPD. Only 44% of those with COPD were eligible for major clinical trials when applying FEV1 < 80% predicted, smoking history of 10 or more pack-years, and no comorbid asthma as common inclusion criteria. During the median 8.9 years of follow-up, we observed 2,130 acute exacerbations and 3,973 deaths in symptomatic smokers. Compared with symptomatic smokers without COPD, multivariable-adjusted hazard ratios for exacerbations were 7.45 (95% confidence interval, 5.41–10.3) and 29.0 (21.1–39.8) in those with COPD, respectively, excluded and eligible for clinical trials. Corresponding hazard ratios for all-cause mortality were 1.21 (1.11–1.31) and 1.67 (1.54–1.81), respectively.
Conclusions: More than half of individuals with COPD in the general population are excluded from major clinical trials; however, these individuals have a clinically significant disease with exacerbations and early death compared with symptomatic smokers without COPD.
Link to abstract
