Cardiovascular outcomes in COPD, obstructive sleep apnoea and the overlap syndrome

Rationale COPD and obstructive sleep apnoea (OSA) are both independently associated with an increased risk of cardiovascular disease. It is not clear whether this risk is further increased in COPD–OSA overlap. We aimed to determine whether COPD–OSA overlap has a higher cardiovascular burden compared with COPD or OSA alone. Methods This was a matched cohort study using electronic health records from the Clinical Practice Research Datalink Aurum database (England). Exposures of interest were a diagnosis of COPD, OSA or both based on validated code lists. Our primary outcome of interest was cardiovascular mortality defined using ICD-10 codes. Our secondary outcomes of interest included: all-cause mortality, incident acute coronary syndrome (ACS), incident stroke and incident heart failure. Results The initial study cohort consisted of 365 667 people with COPD (mean± sd ) age 68±11 years, 59 526 with OSA age 57±11 years and 11 040 with COPD–OSA age 65±10 years. Cardiovascular mortality was significantly higher in patients with COPD–OSA overlap compared with OSA alone (adjusted hazard ratio 1.72 (1.58–1.88); p<0.001) but not compared with COPD alone. People with COPD–OSA overlap had 27% and 58% increased risk of developing ACS compared with COPD and OSA alone respectively, and 69% and 101% increased risk of developing heart failure compared with COPD and OSA respectively. Conclusions We have demonstrated that people with COPD–OSA overlap have a significantly higher cardiovascular burden compared with COPD or OSA alone with real-world implications. Earlier and targeted treatment with cardiovascular optimisation can potentially reduce downstream sequelae.