ORLANDO – More women than men died during the first year of being on the heart transplant waiting list, and the disparity may be influenced by the difference in the use of life-saving therapies, according to a 12-year analysis of a national database.
After adjusting for several variables, researchers found that female gender was associated with a 10% increased risk of being removed from the waiting list because the women died or were deemed too sick during the first year. When the researchers added implantable cardioverter defibrillator use to the analysis, that risk was attenuated to 8%, although still significant, but adding ICDs and left ventricular assist devices (LVADs) eliminated the risk associated with the female gender, said Dr. Alanna Morris of Emory University, Atlanta.
The study, which looked at the Organ Procurement and Transplantation Network (OPTN) database, showed that women on the waiting list were significantly less likely to have an ICD (55% vs. 64%; P less than .001), or a ventricular assist device (24% vs. 30%; P less than .001) than were men, said Dr. Morris, who presented her unpublished abstract at the annual meeting of the Heart Failure Society of America.
The finding is in line with studies that have shown significantly lower rates of ICD implantation among women with end-stage heart failure, compared with men. Research has also shown that women are less likely to be referred for LVAD implantation, even though no survival difference between genders while on LVAD support has been observed, the authors noted.
Meanwhile, the proportion of women on the wait list has increased by more than 4% in the past decade, but studies on women’s survival while on wait lists have shown conflicting results, the researchers added.
They identified nearly 27,000 adult patients (23% were women) in the OPTN database between January 2000 and September 2012, who were listed for their first heart transplant.
There were several statistically significant differences between genders at baseline, aside from ICD and LVAD use. Female heart transplant candidates were younger (52 vs. 56 years), were less likely to have diabetes (21% vs. 27%), were less likely to have a normal glomerular filtration rate (49% vs. 53%), had a lower pulmonary capillary wedge pressure (20 vs. 21 mm Hg), and had fewer median days (67 vs. 84) on a wait list (P less than .001 for all).
The 1-year unadjusted survival rate in women on the waiting list was significantly lower, at 70%, than in men, at 73% (P = .006).
After adjustment for age, race, blood type, and support with extracorporeal membrane oxygenation or intra-aortic balloon pump, female gender was still associated with a higher risk of the primary end point, which was removal from the wait list due to death or being deemed too sick to transplant at 1 year (hazard ratio 1.10; P = .026), the authors reported.
But, after adjustment for ICD and LVAD use, the gender gap was eliminated (HR 1.06; P = .2).
Dr. Morris said that a more aggressive use of these life-saving therapies can eliminate wait-list disparities. The findings also point to the importance of educating community physicians and heart failure patients about the current standards of care, she said.
Changes in the allocation algorithm and improvements in LVAD technology have led to advancements in management of patients on heart transplant waiting lists, the authors said. Between 2001 and 2011, wait list mortality declined from 17 deaths per 100 wait-list years, to 12 deaths. During the same period, wait-list death among patients with an LVAD declined from 102 deaths per 100 wait-list years to 13.
Dr. Morris had no financial relationships to disclose.
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