Among pediatric heart transplant recipients, failure to adhere to immunosuppressive medication is relatively common and is associated with a high mortality rate, researchers found.
Over a 7-year period, 9% of heart transplant recipients younger than 18 were non-adherent at least once, which set back his or her recovery, according to Christopher Almond, MD, MPH, of Boston Children's Hospital, and colleagues.
What's more, the non-adherent patients had a mortality rate of 26% at 1 year and 33% at 2 years, which "is substantially higher than the baseline attrition rate of 3% described in registry reports," the researchers reported online in the Journal of Heart and Lung Transplantation.
Certain factors, including older age, black race, Medicaid insurance coverage, and support from a ventilator or ventricular assist device at the time of transplant, were associated with a greater risk of non-adherence.
"Although these risk factors may not be modifiable, they do define subgroups of patients at risk who may benefit from targeted interventions to monitor and maintain medication adherence over time," Almond and colleagues wrote.
Pediatric patients undergoing heart transplantation are particularly vulnerable to the effects of medication non-adherence "because graft rejection can evolve rapidly from mild to severe congestive heart failure," they wrote. "Without prompt treatment, including initiation of mechanical circulatory support in severe cases, low cardiac output syndrome, respiratory failure, or malignant arrhythmias rapidly progress, culminating in cardiac arrest and death."
To explore the problem, the researchers analyzed Organ Procurement Transplant Network (OPTN) data provided by the United Network for Organ Sharing (UNOS). The study included all patients younger than 18 in the U.S. who underwent orthotopic heart transplantation from October 25, 1999, to January 2, 2007.