People with failing hearts are increasingly being offered implanted battery-powered devices to shock the heart back into a normal rhythm in the case of cardiac arrest. But an Ontario study shows women and several other groups are less likely to receive the potentially life-saving devices.
The researchers analyzed several health-care databases to identify more than 48,000 people who were eligible to receive an implantable cardioverter defibrillator (ICD) for prevention of a first episode of cardiac arrest. The group included people who had suffered a heart attack and within the next five years were hospitalized for heart failure, a condition in which the heart can no longer pump blood properly. The hospitalizations occurred between January 1993 and March 2004.
A total of 440 people received an ICD during hospitalization or during the following year, and use of the devices increased during the study period, rising from an implantation rate of 0.12 per cent in 1993 to 3.9 per cent in 2004.
The results showed ICD implantation was four times more likely in men than women; three times more likely in people younger than 75 than those older; 40 per cent more likely among city dwellers than rural residents; and 30 per cent more likely in patients of higher socioeconomic status than those of lower status.
Dr. Jacob Udell, a study author and research fellow at the Institute for Clinical Evaluative Sciences in Toronto, says it was not surprising to discover that younger people, who may be inherently healthier, or those living in urban areas, where hospitals may have more experience with ICDs, were more likely to receive the devices. The fact that socioeconomic status and gender played such big roles, however, was surprising.
“The question really comes down to … is it a gender discrepancy or is it something in the sexes that would make a man more likely to be eligible versus a woman?” Udell says. “We can’t discern why — even if you account for several of those inherent differences and predispositions — the women were receiving these devices four times less frequently than men.”