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Tackling geographic disparity – Redistribution of livers Ryutaro Hirose, MD Professor, Surgery Vice Chair, UNOS Liver Intestine committee Region 5 Collaborative Las Vegas, NV March 2015
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History - UNOS 1984 – the US Congress passed NOTA (National Organ Transplant Act) – Established the OPTN (Organ Procurement and Transplantation Network) – To maintain a national list of candidates – To establish a national systems to match organs with candidates – To assist OPOs in the nationwide distribution of organs EQUITABLY among transplant patients
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Recent history – liver allocation v 2.0 2000 – US Department of Health and Human Services publishes Final Rule for the operation of the OPTN 2002 – Changes made to use the MELD score to allocate liver allografts
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US Department of HHS Final Rule Allocation of cadaveric organs – the allocation polices: – Shall seek to achieve the best use of donated organs; – Shall be designed to avoid wasting organs, to avoid futile transplants, to promote patient access to transplantation, and to promote the efficient management of organ placement; – Shall not be based on the candidate's place of residence or place of listing
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Sickest first Setting priority rankings…that shall be ordered from most to least medically urgent. There shall be a sufficient number of categories (if categories are used) to avoid grouping together patients with substantially different medical urgency;
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Allocation of scarce resources Demand vs. supply Transplantation is one field that rations medical care Selection committees – Dialysis – Transplant candidacy
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Organ allocation – balancing conflicting principles UTILITY – Maximizing usefulness of scarce resource EFFICIENCY – Cost – Value JUSTICE – Fairness – Equal access
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Deceased donor organs Allocation scheme – How patients are ordered – LIVER: sickest first – LUNG: ratio of yrs added with transplant/mortality pretxp without txp – Kidney: has largely been based on waiting time
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MELD – sickest first MELD =(0.957 x LN(creatinine) + 0.378 x LN(bilirubin) +1.12 x LN(INR) +0.643) x 10 Capped at 40 MELD score is relatively accurate in predicting 3 month waitlist mortality in liver transplant recipients
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Liver – sickest first Status 1 – acute liver failure MELD SCORE – Bilirubin – INR – Cr MELD EXCEPTIONS – Metabolic diseases – HCC
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Map of OPO boundaries/DSA
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UNOS regions
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Organ distribution – SHARE 35 Status 1 – UNOS REGION MELD 35-40 – UNOS REGION MELD 15-34 – local DSA MELD >15 – UNOS REGION Status 1 – National MELD >15 National MELD <15 Local, regional then National
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Share 35 An extension of regional sharing for status 1 patients Expanding access to livers for the sickest patients Pts with MELD scores have >33% risk of dying in a year
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Share 35 Has accomplished intended goals More pts with MELD > 35 are getting transplanted So far, no decrease in outcomes No increase in discards Increase in cold ischemia time modest
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Share 35 BUT some other Increased costs – Transplant centers (sicker pts) – OPOs Increased flyouts Transportation logistics Outside teams, team work (lack thereof) Gaming the system – Accepting multiple offers – Late declines
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Share 35 – needs exposed Need more cooperation, communication Need more transparency Ability of OPOs to see how many offers a center has accepted for a candidate (put limits) Need more agile allocation system (DonorNET) – More offers than 3 centers at a time Change scheme so that livers don’t cross in the air for a single MELD point ?
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HHS: Final Rule Neither place of residence or place of listing shall be a major determinant of access to a transplant
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Metrics of disparity Supply/Demand ratio – Supply – All liver donors? eligible deaths? Potential deaths? All deaths? – Demand – wait listed pts? Pts with ESLD? Variance in transplant rates across DSA/Regions Variance in organ offers across DSA/Regions Variance in drop off rates Variance in waitlist mortality Variance in MELD scores at transplant Variance compared to single national list
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Measuring Disparity Summative metrics – Over the whole country – On average, 40% of the pts with a MELD score of 38- 39 die within 90 days Disparity metric – Range across the country by OPO/DSA – In some DSA’s 18% of pts with MELD 38-39 die within 90 days – In others 82% die – Variance in death across the country by DSAs
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Transplant rates by MELD
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Waitlist deaths by MELD
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Alternatives Different Districts (super-regions), maintaining OPO boundaries as a guide to redistricting Concentric circles around a donor hospital Compare to single national list – full national sharing (lowest disparity)
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Comparing designs/maps Alternative maps generated by contraints and algorithm LSAM simulation models of allocation policy changes Limitations of LSAM – Changes in behavior impossible to model – Listing criteria/Organ acceptance patterns – OPO aggressiveness – Hard to predict, not included in models
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Redistricting objectives Reduce/Minimize total disparity – Difference between the # of organs an area should have (if organ went to highest MELD pt) – organs a region has – Minimize sum of these disparities across all regions Subject to constraints – The minimal disparity is achieved by complete national sharing
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Redistricting constraints At least 4 and no more than 8 districts Minimum # of centers per district: 6 Maximal travel time between DSAs in same Region: 4-5 hours Summative metric: the total # of waitlist deaths under redistrcting must not be higher than current system
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Outputs from LSAM - Metrics SUMMATIVE – Total deaths – Waitlist deaths – Avg transport times – % transportable by car – Avg transport distance – % organs to pts with MELD>25 DISPARITY – Variance of MELD score at transplant across DSAs
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7 regions, 3 hour transport
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4 region
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Comparison to concentric circles Concentric circle – first allocation within circle of 500 miles Advantage – simple, transparent Disadvantage – not superior to optimized maps for decreasing disparity
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Existing geographic disparity
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4 district map reduces disparity
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NEXT LSAM request Add 3 or 5 MELD points for local candidates Local defined by a circle around a donor hospital of 150 vs. 250 miles To avoid livers flying for differences of 1-2 MELD points (some local priority) Will examine all metrics of disparity
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Liver forum – ad hoc subcommittees Metrics of diparity Logistics Finances Increased donation and utilization
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Potential proposals from subcommittees Increase transparency – allow OPOs to see all offers a specific candidate Limit acceptances to 2 livers per candidate Increase # of offers (from 3) to many more on donorNET Expedited placement – More broad offers immediately for suboptimal donors Track acceptance patterns vs. listing criteria for centers
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The US - EXTREMES Currently 28% of The US population lives in a DSA where median MELD at transplant is >29 or <20 After redistricting only 6% of the population will live in DSAs where median MELD scores are that extreme
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Summary Implementation of MELD largely fulfilled ‘sickest first’ Significant geographic disparity exists – policy change is hard to implement – Political forces – Self-interest: fears of transplant centers – Concerns about disparate OPO performance – Concerns about increasing distances, costs
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