Background: Previous studies demonstrated an association between asthma and idiopathic dilated cardiomyopathy (IDCM), raising concerns regarding chronic beta-agonist inhaler use. The purpose of this investigation was to replicate that association.
Methods and results: We identified 67 patients with IDCM and 130 controls with predominately ischemic cardiomyopathy. Patients were administered a structured, detailed phone survey by blinded interviewers, and had chart abstractions performed. We had 80% power to detect an odds ratio (OR) > or = 2.6 for the relation of asthma and IDCM. A history of asthma was present in 19.4% v 12.3% for cases and controls respectively, OR, 1.72, (95% confidence interval [CI], 0.72, 4.09), P = .18. The duration of asthma was higher in cases: 32.3 (19.7) years v 13.8 (15.0) years (P = 0.007). With adjustment for confounders, multivariate analyses revealed no significant relations between asthma or beta-agonist use and the later development of IDCM.
Conclusions: It is unlikely that previously occurring asthma or beta-agonist use has a strong relationship to the development of IDCM; however, IDCM and atopic diseases may cluster in families, warranting further work into the genetic relations between atopy and IDCM.