Women are much less likely to receive an implantable cardioverter-defibrillator for the prevention of sudden cardiac death than men, according to an article published in The Journal of the American Medical Association (JAMA), October 3rd issue.
Although the risk of sudden cardiac death is higher in men than in women, the sex difference closes rapidly in later years – by the age of 85 onwards the risk is the same for both sexes. Sudden cardiac death is a leading cause of death in America, explain the authors.
Implantable cardioverter-defibrillators (ICDs) are effective devices in preventing sudden cardiac death, according to research. Medicare coverage of ICDs has spread. However, many Medicare-eligible patients still do not receive them.
Lesley H. Curtis, Ph.D., Duke University School of Medicine, Durham, N.C., and team looked at the differences between males and females in the receipt of ICDs for the primary and secondary prevention of sudden cardiac death. They collected their data from a 5% national sample of files from the US Centers for Medicare & Medicaid Services for the period 1991-2005. All the patients analyzed in this study were at least 65 years old and had Medicare fee-for-service coverage. They were diagnosed with a heart attack and either heart failure or cardiomyopathy, the primary prevention cohort: 136,421 patients; n = 65,917 men and 70,504 women; or with cardiac arrest or ventricular tachycardia (a cardiac arrhythmia), the secondary prevention cohort: 99,663 patients; n = 52,252 men and 47,411 women, from 1999 through 2005.
In the primary prevention group (2005) 8.6 per 1,000 women received ICD therapy within 12 months of entering the study, compared to 32.3 per 1,000 men. In other words, the men in this group were 3.2 times more likely to receive an ICD. Among the males and females alive at 180 days after group entry, the risk of death in the following year was not substantially lower among those who received ICD therapy, noted the scientists.
In the secondary prevention group (2005), 38.4 per 1,000 women received ICD therapy, compared to 102,2 per 1,000 men. After taking various factors into account, the men in this group were approximately 2.4 times more likely to receive ICD therapy compared to the women. Among both men and women alive at 30 days after entry in this group, the risk of death during the following year was 35% lower for the patients who had received ICD therapy.
The authors concluded “In this longitudinal analysis of Medicare beneficiaries at high risk for sudden cardiac death, we found significant sex differences in the use of ICD therapy from 1999 through 2005. Our findings in this cohort of elderly patients differ from an earlier study that suggested a narrowing of the gap between men and women, and they highlight the need for an improved understanding of sex differences in patterns of care.”
JAMA. 2007;298(13):1517-1524
Written by: Christian Nordqvist