Association between β-blocker use and outcomes in patients with heart failure and chronic obstructive pulmonary disease: a retrospective cohort study.

Heart failure (HF) and chronic obstructive pulmonary disease (COPD) frequently co-occur, complicating treatment. Concerns about respiratory complications often lead to underuse of β-blockers in this population. This study aims to assess the relationship between β-blocker use and clinical outcomes in patients with HF and COPD. This retrospective cohort study utilized the MIMIC-IV v2.2 database. Adult ICU patients with documented HF and COPD diagnoses were identified using international classification of diseases (ICD-9 and ICD-10) diagnostic codes. Propensity score matching (PSM) was applied to reduce confounding bias. Cox regression was used to estimate hazard ratios (HRs), with additional regression and doubly robust methods applied for validation. Subgroup analyses were performed to determine whether the results were consistent across different patient groups. After PSM, β-blocker use was associated with a significantly lower 28-day mortality rate (17.51 vs. 23.98%, P = 0.021), with a HR of 0.667 (95% CI 0.491-0.906). Similar reductions were observed in hospital mortality (13.91 vs. 20.62%, P = 0.010), 60-day mortality (24.46 vs. 30.94%, P = 0.037), and 90-day mortality (27.58 vs. 34.77%, P = 0.025). However, β-blocker users had longer ICU and hospital stays. Subgroup analysis revealed a significant interaction between β-blocker use and mechanical ventilation, with greater mortality reduction observed in ventilated patients (HR: 0.31, 95% CI 0.17-0.56). β-blocker therapy during ICU stay was observed to be associated with improved short-term survival among patients with HF and COPD. These findings suggest that β-blockers may provide substantial survival benefits in this high-risk patient population, despite concerns regarding potential respiratory side effect.