Chronic obstructive pulmonary disease (COPD) and congestive heart failure (CHF) are common and together contribute enormously to the global burden of chronic disease. Although surely these conditions overlap and interact, surprisingly little study has been given to their interrelationship.
Macchia et al prospectively evaluated and followed two cohorts of patients aged > 59, recruited from Spanish outpatient clinics:
- 201 with known stable CHF (with ejection fraction <40%, or at least moderate diastolic dysfunction by established criteria), recruited from cardiology clinics;
- 218 with known stable COPD by spirometry by GOLD criteria (60 pack year history average), recruited from respiratory clinics.
- Only a handful (<10%) in each group were known to have the other comorbidity.
They then checked everyone in each cohort for the other condition (by spirometry or echocardiography):
- 17% of COPD patients had coexisting left ventricular dysfunction (systolic or diastolic).
- 37% of CHF patients had at least mild airway obstruction by GOLD criteria; 12% (n=25) had GOLD III (FEV1 < 50% predicted).
There were 61 deaths during 2 year followup. The COPD patients with coexisting LV dysfunction had a hazard ratio of 2.34 for death during follow up (compared to COPD patients with normal LV function).
The CHF patients with concomitant airflow obstruction were not at increased risk of death; however, it appeared (to me) there was an insufficient sample size to stratify the risk according to severity of COPD (only 26 patients in the CHF cohort had GOLD stage III-IV COPD).
Macchia A et al. Unrecognised ventricular dysfunction in COPD. Eur Resp J 2011;39:51-58.