The study was designed to evaluate primary prevention ICD trials that assessed gender differences with the end points of total mortality, appropriate ICD interventions and survival benefits compared to placebo. The meta-analysis study included 7,229 patients, 22 percent women, with dilated cardiomyopathy enrolled in five different studies: MADIT-II, MUSTT, SCD-HeFT, DEFINITE and COMPANION. To ensure direct comparisons between women and men, analysis for each study was adjusted for the maximum number of confounding factors and covariates in order to provide approximations that would be affected the least by standard gender differences.
Overall study findings revealed women had the same overall mortality as men (hazard ratio 0.96, p = 0.84). However, women experienced significantly less ICD interventions on rapid sustained ventricular tachycardia or fibrillation than men (hazard ratio 0.63, p ≤ 0.001), suggesting that women are less likely to suffer from SCD. Additionally, among men ICD therapy was associated with a 33 percent reduction of total mortality compared to the placebo group while women had a smaller and nonsignificant reduction of mortality.
“Our main focus was to compare women to men when it came to clinical outcomes following prophylactic ICD placement to determine if certain subgroups of patients should be treated differently,” said lead author Pasquale Santangeli of the Cardiology Department at Catholic University in Rome, Italy. “We believe that our findings may explain why women have a smaller and nonsignificant survival benefits from prophylactic ICD therapy and the importance for further studies to be done on this underrepresented subgroup – women.”
Many studies previously conducted have underrepresented women in primary prevention ICD trials, and this study demonstrates that women do benefit differently from ICD therapies than men. Therefore, the study suggests that women should be considered more often in trials to continue discoveries for the best outcomes and preventative measures for each gender.
For more information about this study, please visit www.heartrhythmjournal.com.
About HeartRhythm Journal
HeartRhythm, the official journal of the Heart Rhythm Society, provides rapid publication of the most important science developments in the field of arrhythmias and cardiovascular electrophysiology (EP). As the official journal of the Heart Rhythm Society, HeartRhythm publishes both basic and clinical subject matter of scientific excellence devoted to the EP of the heart and blood vessels, as well as therapy. The journal is the only EP publication serving the entire electrophysiology community from basic to clinical academic researchers, private practitioners, technicians, industry and trainees. HeartRhythm has an impact factor of 4.444 (as of 2008) and ranks 11th out of 78 cardiovascular medicine journals worldwide by the Institute for Scientific Information, remaining the #1 specialty journal in cardiology. Additionally, the journal ranks seventh in the Immediacy Index among cardiology publications. It is also the official publication of the Cardiac Electrophysiology Society.
Contact: Kennesha Baldwin
Heart Rhythm Society