Projections of US Donor Organ Availability for Liver Transplantation.

Abstract

The number of donor organs available for liver transplantation has plateaued in the US in recent years, leading to limits in the ability to expand liver transplantation. With the ageing US population and obesity epidemic, there is potential for further exacerbation of the donor shortage. We aimed to project the availability of liver grafts over the coming decade in the US. We performed a secondary analysis of the UNOS OPTN database of all adult liver transplant recipients and all adult organ donors from 1999-2012. We calculated the total number of potential donors available and donor livers transplanted, stratified by age and BMI group per year. We then used US population data projections provided by the Centers for Disease Control and projected donor availability and organ utilization from 2014-2023. We projected using the highest and lowest organ utilization rates present in the UNOS data set and the average utilization rate from 2008-2012. Given recent evidence that the obesity rate in the US has stabilized, we assumed the obesity rate would remain constant over the next decade. From 1999-2005 there was a 37.3% increase in available donors and a 43.6% increase in the number of utilized livers. However from 2005-2012 the number available donors and utilized organs plateaued with a 3.2% decrease in the number of available donors and a 1.0% decrease in the number of utilized livers. Figure 1 shows the projections using the best utilization rates, worst utilization rates and average from 2007-2012.Figure: No Caption available.The projected adult population growth in the US from 2014-2023 will be 8.1%. However, we project there will be a 4.6% increase in the number of available donors and a 5.4% increase in the number of utilized liver grafts. The overall US adult population growth will outpace the growth of available donor organs, thus likely exacerbating the existing liver graft shortage. Strategies to increase organ availability are warranted in order to alleviate this shortage and prevent waitlist dropout.