Transcript UNOS Kidney Committee Allocation Concepts: Not As Different As Some Want You to Believe… Ken Andreoni, MD Chair UNOS Kidney Comm The Ohio State University OPTN DD Kidney.

UNOS Kidney Committee
Allocation Concepts:
Not As Different As Some Want
You to Believe…
Ken Andreoni, MD
Chair UNOS Kidney Comm
The Ohio State University
OPTN
DD Kidney Allocation
Concepts
 We
are ONLY talking about standard ADULT
Kidney only allocation today. We are NOT
talking about:
•
•
•
•
•
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Kidney with extra-renal organ (LK, HK, KP, etc.)
Pediatric – no change (except KDPI, not age)
Prior Living Donor category
O-MM National Sharing (CPRA >20)
Geography: being thoroughly investigated by other
UNOS committees; complex issue
DD Kidney Allocation
Concepts
 Though
we think of allocating 10,000
deceased donor kidneys a year in the US,
allocation is one kidney at a time…
• This is why many theoretical allocation concepts
do not work in reality!
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DD Kidney Allocation:
Recent Change
0
mm ABDR is local by category of CPRA,
then regional or national for CPRA >20 only
• This change has decreased the share of
unsensitized 0 mm, and allowed more highly
sensitized candidates to be transplanted nationally
with less overall shipping of kidneys
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DD Kidney Allocation: TODAY
 Estimation
of DD kidney graft potential
function: ECD or SCD
 If ECD: goes to those on the local ECD list
(by wait time)
• If not accepted, then regional, then national ECD
lists
 If
SCD: then all candidates locally by “points”
• Wait time, HLA-DR matching (2 pts max), CPRA
(>80 = 4 pts)
• Then regional, then national by pts
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DD Kidney Allocation: TODAY
 Most
candidates at the top of list mostly by
Wait Time
• “If I just wait another week/month, could I get a
much better kidney?”
• Makes very inefficient use of very useable
kidneys
• Patients and Transplant Professionals need
better educational tools to decide about the
trade-off: time to transplant vs. quality of organ
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DD Kidney New Allocation:
Concepts (not policy)
 Estimation
of DD kidney graft potential
function: ECD or SCD “KDPI”: < or > 20%
 If KDPI is 21 to 100%, first offered to all within
15 years of donor age (30 yr span)
• This large group rank ordered (WT, CPRA, HLA)
• If not accepted, then to those outside of 15 yrs
local, then regional, then national
 If
KDPI <=20%; then first to candidates with
Est Post-Tx Survival longest 20%
• If not accepted, then to all local, then regional,
then national
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SCD vs ECD: Overlap
SCD
 Too
2 5%
% of transplants per group
many
candidates are
listed for ECD
 Waiting for the
‘Good ECD’
ECD (16.6% of total transplants)
20%
15%
10 %
5%
DRI Categories
Despite this survival overlap, the current system
leads to higher discard rates for potential well
functioning kidneys that are labeled ECD
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0+
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.2
1.
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.6
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2.
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0%
KDPI vs ECD
 KDPI
•
•
•
•
•
•
•
•
•
•
Donor age (c)
Race/ethnicity
Hypertension
Diabetes
Serum creatinine (c)
COD CVA
Height
Weight
DCD
HCV
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 ECD
• Donor Age
• >60 alone
• Donor Age
• >50 with two below:
• Cr >1.5
• HTN
• CVA
• RR of graft failure >1.7
compared to the ‘ideal’
donor (16 – 17%)
Donor Age v. KDPI
KDPI overlaps
substantially for
donors from most age
categories
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Slide 10
Donor Age by Recipient Age
2005-2007 Transplanted Kidney-Alone Donors
80
70
Donor Age
60
50
40
30
20
10
0
20 - 30
30 - 40
40 - 50
50 - 60
60 - 70
70 - 80
80 - 90
Recipient Age
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Slide 11
RR Graft Failure (DPI eqn)
Distribution of Relative Risks for
Donor Kidneys: 2004-2007
10
8.89
9
8
Relative Risk for
graft failure is not
7
markedly different for
6
top 20% of kidneys
5
3.26
4
2.78
2.47
2.22
2.01
3
3.70
1.66 1.83
1.50
2 1.00 1.35
1
1.28
0
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Percentile Among 2004-2007 Donor Kidneys
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Uses donor factors only
+- 15 years: mostly what we
already do…
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


Median age difference is
14 years in the US
• 25% of DD txs <6 yrs
apart
• 75% < 26 yrs apart
Donors <35 yo are 41% of
donors
Donors <=35, mean
recipient age is 49
Recip >65 more than half
of donors >50yo
OPTN
Segev DL. Evaluating Options… AJT 2009; 9:1513-18
DD Kidney Utilization
 Estimation
of DD kidney graft potential
function:
• ECD/SCD vs KDPI
 Education
of potential benefit to
recipients (and transplant professionals)
• Quality of organ vs. prolonged wait time for
better organ
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Median Remaining
Lifespan (years)
Median Expected Survival by Age
for Active Kidney Candidates,
1/1/2004
60
50
40
General Population
30
With SCD Transplant
20
With ECD Transplant
10
0
Without Transplant
20
30
40
50
60
70
Age (years)
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Wolfe et al, SRTR
simulation models
Median Expected Survival by Age
Average of Median Survival of
Candidates
Active Kidney Candidates, 1/1/2004
25
With Average SCD Transplant
20
With Average ECD Transplant
15
10
5
Without Transplant
0
20
30
40
50
60
Age at Transplant
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Wolfe et al, SRTR Simulation Models
70
80
Recipient Survival by Recipient
Age and Donor DPI
Median Patient Survival
DPI
0 - 19
35
30
32
3029
2827
25
20 - 39
2625
2423
21
20
40 - 59
2120
19
18
16
15
60 - 79
1514
1312
11
10
1111
10 9
80 - 100
8
9 8 7
7 6
5
0
20 - 29
30 - 39
40 - 49
50 - 59
60 - 69
70+
Recipient Age
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2005-2007 transplants
Slide 17
Hypothetical Output from an Educational Tool to help
Candidates and Transplant Professionals Make More
Informed Decisions on Organ Acceptance:
Candidate of X yrs old, with Y, Z co-morbidities, living
in a DSA C
5
4
3 2
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1
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The easy potential increase
in kidney utilization
DD Kidney Utilization
 Estimation
of DD kidney graft potential
function:
• ECD/SCD vs KDPI
 Education
of potential benefit to
recipients
 Transplant Center Outcome reports
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% Deaths by Year
by DPI among
candidates >50 by
decade of age
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Big Picture Slide: Most with ESRD do not live
to avg. pop lifetime, Transplantation is good
for most candidates, young w ESRD lose
more years from their expected lifetime
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Who is the Sickest?
 Die
first?
• Like MELD for liver
• Then we transplant all sicker and older pts
 Who
loses the most years from their disease?
• 25yo on HD:13 yrs, w Tx:34 yrs
• 60yo on HD: 5 yrs, w Tx:12 yrs
• 25yo unlikely to reach age 60 w Tx
• 25yo will die at <40 yrs of age on HD
• 25yo gains 21 yrs of survival, 60yo gains 7 yrs
of survival w Tx
• 25yo lives 13 yrs on HD, 60yo lives 12 yrs w Tx
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‘A Kidney That Looks Like You’
 All
candidates of all ages have access
• Access for most candidates does NOT change
• The average candidate will receive the SAME quality
kidney
• Will only prevent transplantation across many
decades of age differences
 All
candidates may benefit…why?
• Improvement of utilization of kidneys by KDPI and
understanding of age ranges should increase
transplantation of appropriate kidneys, especially to
older candidates
• Public understanding of system to increase donation
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‘A Kidney That Looks Like You’
 Living
Donation should not be influenced in the
negative: No one goes to the front of the line
• Whether within 30 year age group, or “top 20%”
everyone within that group is then equal and put in
order by variables such as: Wait time, CPRA, HLA,
etc., so everyone will wait for their DD offer
• NOT similar to the Pediatric Share 35 situation
that occurred in some DSAs
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Is the Data Good Enough?
 80%
of organs first to candidate group within 15
years (30 yr range)
• Rank-ordered by variables similar to today such as
Wait Time, CPRA, HLA match, etc.
• Clinical common sense
• Alignment of potential function of organ to posttransplant potential survival
 20%
DPI and EPTS
• Predictive models are reasonably good to
predict the longest potential functioning
organs and longest surviving recipient
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C Statistic
 Measure
of “goodness of fit”, or how
accurately does this tool tell two people
apart everywhere on the list
• It gives the same weight to tell number 1
from number 10,000, as it does from telling
number 5,000 from number 5,001
• The first is important in allocation, the later is
not!
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Is the Data Good Enough?
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Thank you
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