Study: COPD Comorbidity Can Increase Risk of All-Cause Mortality in Heart Failure

A recent meta-analysis examined the effect of chronic obstructive pulmonary disease (COPD) on hospitalization and mortality in patients with heart failure (HF) and reported an association between the presence of COPD and an increased risk of long-term all-cause mortality.

HF is a considerably complex clinical syndrome; patients with HF have several morbidities, including diabetes mellitus, coronary artery disease, atrial fibrillation, hypertension, and lung disease, according to study investigators. The prevalence of COPD in patients with HF ranges from 10% to 20% in randomized controlled trials (RCTs) and observational studies.

Previous studies have suggested the increased risks of hospitalization and death associated with a diagnosis of HF among patients with COPD, but the implications of such a diagnosis remains unclear, according to researchers of the study.

The study utilized meta-analysis according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Researchers systematically searched several databases, including PubMed, EMBASE, Google Scholar, and Cochrane library, with the following search terms: heart failure, HF, chronic obstructive pulmonary disease, COPD, outcome, prognosis, death, mortality, hospitalization and readmission. Retrieved studies were screened for relevance and quality, among other characteristics.

Following systemized review and exclusion, researchers identified a total of 18 studies to include in the meta-analysis: 6 post hoc analyses of RCTs and 12 observational studies. Eight of the included studies enrolled hospitalized patients with HF; 9 studies enrolled patients with chronic HF; and 1 study included both patients with hospitalized HF and chronic HF.

The pooled data demonstrated an increased risk of long-term all-cause mortality in patients with hospitalized HF or chronic HF. Investigators also reported that COPD was associated with increased risks of all-cause hospitalization, as well as HF hospitalization in patients with chronic HF.

Investigators identified 3 limitations of the study:

1. The meta-analysis was not registered on the PROSPERO database.
2. Some confidence intervals in the results were relatively wide due to limited sample size and the small number of events.
3. Future research should confirm the findings on hospitalization due to the limited number of studies that focused on this outcome.

“Based on current publications, our meta‐analysis suggested that COPD comorbidity could increase the risk of long‐term all‐cause mortality of HF patients,” the study authors concluded.

Reference:

1. Xu S, Ye Z, Ma J, et al. The impact of chronic obstructive pulmonary disease on hospitalization and mortality in patients with heart failure. European Journal of Clinical Investigation. September 11, 2020. doi: https://doi.org/10.1111/eci.13402.