Introduction

OPTN/SRTR 2016 Annual Data Report: Introduction

Introduction for the OPTN/SRTR 2016 Annual Data Report

This introduction provides a brief overview of trends in waitlist and transplant activity for solid organs in the United States. Explanations of trends vary substantially by organ type, and details can be found in the respective organ-specific Annual Data Report chapters. The 2016 Annual Data Report covers transplants through the end of 2016.

Trends in Kidney Transplantation

Arguably, the most remarkable trend in transplantation has been the increase in deceased donor kidney transplants, which more than made up for declines in living donor kidney transplants. In 2016, for the first time in a decade, the number of candidates active on the deceased donor kidney transplant waiting list declined, by 2.2% (Figure INT 1). Between 2005 and 2014, the number of active candidates grew by 29.1%, an annual rate of growth of 2.9%. However, between 2014 and 2015, the increase was only 0.7% and between 2015 and 2016, the number declined. This decline was due to more transplants performed and not to fewer patients added to the waiting list (Figure KI 1, Figure KI 92, and Figure KI 48 in the kidney chapter). Indeed, between 2015 and 2016, the number of new patients (active and inactive) added to the waiting list grew by 1.9% (Figure INT 3).

The number of kidney transplants grew by 6.8% between 2015 and 2016, from 18,597 to 19,859 (Figure INT 5). This increase was entirely due to a 9.7% increase in deceased donor transplants, from 12,969 to 14,229 (Figure KI 48 in the kidney chapter). The number of living donor transplants was unchanged, 5630 in 2016 and 5628 in 2015.

The increase in the number of deceased donor kidney transplants and the corresponding decline in the number of patients on the waiting list coincides with implementation of the new kidney allocation system (KAS) in December 2014. At the time of implementation, there was concern that allowing waiting time to commence at the time of dialysis initiation for end-stage renal disease, rather than at the time of listing, would decrease the number of candidates added to the waiting list. However, the effect on additions to the waiting list appears to be minimal. Possibly, the increase in deceased donor kidney transplants is a “bolus” effect of the KAS. The increase could also be due to higher utilization of kidneys, especially given the epidemic of opioid-related drug overdoses. Nevertheless, a growing proportion of kidneys are retrieved for transplant and not transplanted (Figure INT 7). In 2016, 20.0% of retrieved kidneys were not transplanted, and it is likely that many would be suitable for candidates on the waiting list.

Trends in Pancreas Transplantation

Demand for pancreas transplants declined over the past decade. Between 2007 and 2016, the year-end number of active candidates on the waiting list for simultaneous pancreas and kidney transplant declined by 35.0% and for pancreas transplant without kidney by 47.9% (Figure INT 2). Numbers of new additions to these waiting lists also declined (Figure INT 4). Between 2015 and 2016, the number of pancreas transplants without kidney declined by 5.7%. However, as the number of simultaneous pancreas and kidney transplants increased 11.0%, the total number of pancreas transplants increased 7.0% between 2015 and 2016 (Figure PA 34 in the pancreas chapter). The rate of discard declined slightly between 2015 and 2016 (Figure INT 7); the availability of pancreata for transplant is not currently a concern.

Trends in Liver Transplantation

The second most common organ transplanted in the US is liver. The number of active liver transplant candidates on the waiting list has been slowly declining since 2013 (Figure INT 1). From year-end 2015 to 2016, the number declined by 4.4%. The number of new additions (active and inactive) to the waiting list increased by 17.1% between 2007 and 2016, and by 6.5% between 2015 and 2016 (Figure INT 3). The number of liver transplants increased by 20.7% between 2007 and 2016 (Figure INT 5). The 10.0% increase in liver transplants between 2015 and 2016 was the largest 1-year increase in a decade (Figure INT 5), and was entirely due to a 10.8% increase in deceased donor liver transplants; numbers of living donor liver transplants were 359 in 2015 and 345 in 2016 (Figure LI 36 in the liver chapter). The percentage of livers recovered for transplant but not transplanted declined by 20.6% between 2007 and 2016, and by 5.3% between 2015 and 2016 (Figure INT 7).

Trends in Intestine Transplantation

The number of intestine transplants remains small. In 2016, 147 intestine transplants were performed. Between 2007 and 2017, the number of intestine transplants declined by 25.8%, from 198 to 147 (Figure INT 6). During this time, the number of candidates on the waiting list increased 20.2%, from 168 to 202 (Figure INT 2).

Trends in Heart Transplantation

The demand for heart transplants continues to grow. In the past decade, the number of active candidates on the heart transplant waiting list at year-end increased 118%, from 1432 in 2007 to 3118 in 2016 (Figure INT 2). During this time, the number of new active and inactive candidates added to the list increased by 37.9% (Figure INT 4). The number of heart transplants increased by 43.3% in the past decade, and by 13.8% between 2015 and 2016 (Figure INT 6). In 2016, 3209 heart transplants were performed, a record number, but 4254 candidates were added to the waiting list.

Trends in Lung Transplantation

Increases in numbers of lung transplants continue to exceed those for any other organ. Between 2007 and 2016, the number of lung transplants increased 56.4%, from 1499 to 2345 (Figure INT 6), and between 2015 and 2016 by 13.2%. The number of active candidates on the lung transplant waiting list at year-end grew by 10.4% over the past decade (Figure INT 2), while the number of active and inactive new additions to the waiting list increased by 40.7% over the same period (Figure INT 4). The proportion of lungs retrieved for transplant but not transplanted increased, but remains relatively low, 6.1% in 2016 (Figure INT 7).

Summary

The recent noteworthy increase in the number of deceased donor kidney transplants has, for the first time in a decade, been associated with a decline in the number of candidates active on the kidney transplant waiting list. Nevertheless, the proportion of kidneys retrieved for transplant but not transplanted continued to grow and reached 20% in 2016. The number of simultaneous kidney and pancreas transplants increased in 2016, reversing a decade-long declining trend. The number of liver transplants continues to grow and continues to be inadequate to meet the demand. Heart and lung transplants have shown the greatest growth over the past decade.

Figure List

Intro

Figure INT 1. Candidates active on the kidney or liver waiting list on December 31 of the year
Figure INT 2. Candidates active on the waiting list for organs other than isolated kidney or liver on December 31 of the year
Figure INT 3. New candidates added to the kidney or liver waiting list during the year
Figure INT 4. New candidates added to the waiting list during the year for organs other than isolated kidney or liver
Figure INT 5. Total counts of kidney or liver transplants
Figure INT 6. Total counts of transplants for organs other than isolated kidney or liver
Figure INT 7. Rates of organs recovered for transplant and not transplanted

A line plot for candidates active on the kidney or liver waiting list on december 31 of the year; the kidney category increases by 27.3% from 47.6 candidates (in thousands) at 2005 to 60.6 candidates (in thousands) at 2016; and the liver category is 12.7 candidates (in thousands) at 2005 and remains relatively constant with a value of 11.5 candidates (in thousands) at 2016. — **Figure INT 1. Candidates active on the kidney or liver waiting list on December 31 of the year**
Candidates concurrently listed at multiple centers are counted once. Those with concurrent listings and active at any program are considered active. Active status is assessed on December 31 of the year.

A line plot for candidates active on the waiting list for organs other than isolated kidney or liver on december 31 of the year; the kidney to pancreas category decreases by 42.4% from 1.5 candidates (in thousands) at 2005 to 0.9 candidates (in thousands) at 2016; the pancreas (pta+pak) category decreases by 53.9% from 0.5 candidates (in thousands) at 2005 to 0.2 candidates (in thousands) at 2016; the intestine category increases by 35.6% from 0.1 candidates (in thousands) at 2005 to 0.2 candidates (in thousands) at 2016; the heart category increases by 128.3% from 1.4 candidates (in thousands) at 2005 to 3.1 candidates (in thousands) at 2016; and the lung category is 1.1 candidates (in thousands) at 2005 and remains relatively constant with a value of 1.1 candidates (in thousands) at 2016. — **Figure INT 2. Candidates active on the waiting list for organs other than isolated kidney or liver on December 31 of the year**
Candidates concurrently listed at multiple centers are counted once. Those with concurrent listings and active at any program are considered active. PAK, pancreas after kidney; PTA, pancreas transplant alone. Active status is assessed on December 31 of the year.

A line plot for new candidates added to the kidney or liver waiting list during the year; the kidney category increases by 18.6% from 26.3 candidates (in thousands) at 2005 to 31.2 candidates (in thousands) at 2016; and the liver category increases by 18.5% from 10.2 candidates (in thousands) at 2005 to 12.1 candidates (in thousands) at 2016. — **Figure INT 3. New candidates added to the kidney or liver waiting list during the year**
A new candidate is one who first joined the list during the given year, without having been listed in a previous year. Previously listed candidates who underwent transplant and subsequently relisted are considered new. Candidates concurrently listed at multiple centers are counted once. Active and inactive patients are included; active status for kidney candidates is determined on day 7 after first listing.

A line plot for new candidates added to the waiting list during the year for organs other than isolated kidney or liver; the kidney to pancreas category decreases by 31.8% from 1.6 candidates (in thousands) at 2005 to 1.1 candidates (in thousands) at 2016; the pancreas (pta+pak) category decreases by 55.7% from 0.8 candidates (in thousands) at 2005 to 0.4 candidates (in thousands) at 2016; the intestine category decreases by 28.3% from 0.3 candidates (in thousands) at 2005 to 0.2 candidates (in thousands) at 2016; the heart category increases by 52.4% from 2.8 candidates (in thousands) at 2005 to 4.3 candidates (in thousands) at 2016; and the lung category increases by 78.3% from 1.5 candidates (in thousands) at 2005 to 2.7 candidates (in thousands) at 2016. — **Figure INT 4. New candidates added to the waiting list during the year for organs other than isolated kidney or liver**
A new candidate is one who first joined the list during the given year, without having been listed in a previous year. Previously listed candidates who underwent transplant and subsequently relisted are considered new. Candidates concurrently listed at multiple centers are counted once. Active and inactive patients are included. PAK, pancreas after kidney; PTA, pancreas transplant alone.

A line plot for total counts of kidney or liver transplants; the kidney category increases by 14.2% from 17.4 transplants (in thousands) at 2005 to 19.9 transplants (in thousands) at 2016; and the liver category increases by 21.7% from 6.4 transplants (in thousands) at 2005 to 7.8 transplants (in thousands) at 2016. — **Figure INT 5. Total counts of kidney or liver transplants**
Kidney: patients undergoing kidney or SPK transplant. Retransplants and multi-organ transplants are included. SPK, simultaneous pancreas-kidney.

A line plot for total counts of transplants for organs other than isolated kidney or liver; the pancreas category decreases by 29.9% from 1.4 transplants (in thousands) at 2005 to 1 transplants (in thousands) at 2016; the intestine category decreases by 17.4% from 0.2 transplants (in thousands) at 2005 to 0.1 transplants (in thousands) at 2016; the heart category increases by 48.6% from 2.2 transplants (in thousands) at 2005 to 3.2 transplants (in thousands) at 2016; and the lung category increases by 62.7% from 1.4 transplants (in thousands) at 2005 to 2.3 transplants (in thousands) at 2016. — **Figure INT 6. Total counts of transplants for organs other than isolated kidney or liver**
Pancreas: patients undergoing pancreas or SPK transplant. Heart: patients undergoing heart or heart-lung transplant. Lung: patients undergoing lung or heart-lung transplant. Retransplants and multi-organ transplants are included. SPK, simultaneous pancreas-kidney.

A line plot for rates of organs recovered for transplant and not transplanted; the kidney category increases by 20.6% from 16.6 percent at 2005 to 20 percent at 2016; the pancreas category decreases by 16.6% from 28.7 percent at 2005 to 24 percent at 2016; the liver category is 9.7 percent at 2005 and remains relatively constant with a value of 9 percent at 2016; the intestine category decreases by 31.8% from 7.6 percent at 2005 to 5.2 percent at 2016; the heart category decreases by 29.2% from 1.4 percent at 2005 to 1 percent at 2016; and the lung category increases by 52.6% from 4 percent at 2005 to 6.1 percent at 2016. — **Figure INT 7. Rates of organs recovered for transplant and not transplanted**
Percentage of organs not transplanted out of all organs recovered for transplant. Kidneys recovered en-bloc are counted once, and kidneys recovered separately are counted twice.