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Original article
Risk-adjusted survival in liver transplant patients assessed and managed by a non-transplanting centre: South West Liver Unit experience
  1. Benjamin Charles Norton1,2,
  2. Ankur Srivastava3,
  3. Katie Ramos2,
  4. Louisa Vine2,
  5. Rhiannon Taylor4,
  6. Varuna Aluvihare5,
  7. Nigel Heaton5,
  8. Matthew E Cramp2
  1. 1General Medicine, King's College Hospital, London, UK
  2. 2South West Liver Unit, Plymouth Hospitals NHS Trust, Plymouth, UK
  3. 3Department of Gastroenterology and Hepatology, Southmead Hospital, Bristol, UK
  4. 4Statistics and Clinical Studies, NHS Blood and Transplant, Watford, Hertfordshire, UK
  5. 5Institute of Liver Studies, Department of Hepatology, King's College Hospital, London, UK
  1. Correspondence to Dr Benjamin Charles Norton, General Medicine, King's College Hospital, London, UK, SE5 9RS; benjamin.norton{at}nhs.net

Abstract

Background Liver transplant services remain a scarce resource not reflective of geography or burden of liver disease within the UK. To address geographical concerns in the South West (SW), a devolved network model of care for liver transplantation was established in 2004 between the SW Liver Unit (SWLU) at Derriford Hospital, Plymouth and King’s College Hospital, London. The SWLU has evolved to deliver both pre-transplant and post-transplant care for patients across the SW Peninsula. We determined whether risk-adjusted survival in patients assessed and managed at the SWLU compared with existing UK transplant centres.

Design Retrospective analysis of records at National Health Service Blood and Transplant (NHSBT) for patients ≥18 years listed or undergoing first liver only deceased donor transplantation from 1 January 2006 to 31 December 2017. Data collected and used were in accordance with standard NHSBT outcome measures.

Results We identified 8492 patients registered for first liver only transplant and 6140 patients who subsequently underwent transplantation. Of these, 215 patients listed and 172 patients transplanted were registered at the SWLU. The 1-year, 5-year and 10-year risk-adjusted post-listing survival for patients registered at the SWLU were 86%, 75% and 67%, respectively, with 1-year and 5-year risk-adjusted post-transplant survival 94.9% and 84.4%, respectively.

Conclusions Risk-adjusted post-listing 1-year, 5-year and 10-year survival outcomes and risk-adjusted 1-year and 5-year post-transplant survival outcomes at the SWLU are good and comparable with the seven UK transplant centres. These outcomes provide assurance that care delivered by our regional programme is equivalent to well-established liver transplant programmes.

  • liver transplantation
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Introduction

Liver disease is a major cause of premature death in the UK, with liver-related deaths increasing fivefold since the 1970s.1 Chronic liver disease (CLD) now represents the fourth most common cause of years of life lost in those aged under 75.2 Annual admissions to hospital with liver-related pathology are rising rapidly, largely due to complications of end-stage liver disease.3 The rising prevalence of advanced CLD means there is a growing cohort of patients who could benefit from liver transplantation. Since 2008, the number of patients on the active liver transplant list has doubled, and over the last 10 years, 6170 adult patients underwent liver transplantation, which remains the only definitive treatment for many patients.3 The number of patients undergoing liver transplantation from a deceased donor has risen significantly from 633 in 2008–2009 to 946 in 2016–2017, in parallel with a rise in organ donation rates.4

Despite the rise in liver-related mortality, specialist liver transplant services remain a resource that does not reflect the geography or burden of liver disease within the UK with seven liver transplant units and none in the South West (SW). The Lancet Commission on Liver Disease in the UK has highlighted the need to review the provision of liver transplantation services to ensure better access to care for patients, particularly focusing on regions with the highest liver disease rates or without transplant services.5 6 In the SW region of England, the proportion of patients aged 18 years and over presenting with complications of liver disease is a significant issue, with approximately 155 per 100 000 adults admitted with cirrhosis in 2014/2015.6 A recent paper confirmed that travel time is significantly correlated with worsened outcome from the point of listing for liver transplantation and a lower likelihood of receiving a liver transplant in the UK.7 The SW of England has no liver transplant unit with patients facing a journey from 200 to over 300 miles to reach the nearest liver transplant centre, representing some of the longest distances and journey times faced by patients for healthcare within the UK.8

In 2004, to address some of these concerns, the SW Liver Unit (SWLU) at Derriford Hospital, Plymouth, established a formal network with King’s College Hospital (KCH), London, to create a devolved model of care for liver transplant patients involving a large regional centre and its referring hospitals. In parallel, a clinical hepatology network covering the SW Peninsula was established with referring hospitals in Barnstaple, Exeter, Taunton, Torbay and Truro. Through these networks, the SWLU delivers transplant assessment, pre-transplant care and post-transplant care for patients from the SW Peninsula. The SWLU undertakes the full liver transplant assessment and presents the case at the King’s listing meeting via audiovisual link. If taken forward, the patient visits King’s on a single occasion for completion of their education and orientation and to meet the clinical team. Once listed, all patient care is delivered through the SWLU with no further visits to Kings until the time of liver transplantation. Post-transplant inpatient repatriation to the SWLU occurs early once clinically stable, typically around day seven. All subsequent post-transplant care, both inpatient and outpatient, is delivered regionally by the SWLU, and whenever possible by the patients’ local hospital. All usual post-transplant problems are dealt with locally with patients only returning to King’s for regrafting. A joint SWLU/King’s transplant multidisciplinary team meeting and clinic for the whole region is held 3–4 times per year. This network differs from others recently reported9 in that it has matured and evolved over a 14-year period as a devolved care model, rather than a hub and spoke, with pre-transplant and post-transplant care devolved fully to a large regional centre providing 24/7 consultant hepatology cover.

This care model has enabled local patients and their families to receive specialist liver care in relative proximity to their home for over 10 years. The clinical networks have evolved and matured as teams and services have grown and developed. In this paper, we have utilised National Health Service Blood and Transplant (NHSBT) outcome modelling to evaluate short-term, medium and long-term outcomes for patients receiving devolved care at the SWLU compared with the current established UK transplant centres.

Methods

All patients 18 years or older from Devon, Cornwall and Somerset assessed by the SWLU and registered at KCH for a first liver only transplant between 1 January 2006 and 31 December 2017 were identified on the NHSBT database. Patients registered at hospitals outside the network or at other transplant centres were excluded. This allowed extraction of the SWLU cohort from the largest NHSBT database. The remaining NHSBT population of first liver only transplants between these dates were then reanalysed in accordance with previously documented methodology, to allow risk-adjusted comparisons.3 In both populations, patients listed as ‘super urgent’ were excluded. Baseline demographic data alongside donor and transplant data were determined at the SWLU, KCH and nationally from the NHSBT database. We then determined the risk-adjusted post-listing and post-transplant survival to allow comparisons between known differences in centre demographics.

Survival from time of listing cohort

Risk-adjusted 1-year, 5-year and 10-year survival outcomes were calculated using standardised NHSBT outcome modelling. Data at registration used to risk adjust patient survival from listing can be found in the NHSBT Annual Report for Liver Transplantation 2017.3 Cox proportional hazards models were used to perform adjusted survival analysis, which is based on individual risk factors including clinical and biochemical parameters, aetiology and demographic data. Survival time was defined as the time from joining the transplant list to death, regardless of the length of time on the transplant list, whether the patient was transplanted or not and any factors associated with the transplant (eg, donor type). Survival time was censored at the date of removal from the list, or at the last known follow-up date post-transplant when no death date was recorded or 27 November 2018 if the patient was on the transplant list at the time of analysis.

Post-transplant survival cohort

Risk-adjusted 1-year and 5-year survival outcomes were calculated using standardised NHSBT outcome models. One-year patient post-transplant survival was estimated for transplants performed between 1 January 2006 and 31 December 2017, and 5-year patient post-transplant survival was estimated for transplants performed between 1 January 2006 and 31 December 2012. Data at transplant used to risk-adjust patient survival post-transplantation can be found in the NHSBT Annual Report for Liver Transplantation 2017.3 Cox proportional hazards models were used as discussed above. Death, irrespective of whether the graft is still functioning or not, was classed as an event. If a patient was alive at the end of follow-up, then information about the survival of the patient was censored at the time of analysis.

Results

Baseline demographic data comparing patients listed for liver transplant from the SWLU, KCH and nationally are shown in table 1. When compared with KCH, the median age of patients at the SWLU was higher (57 vs 54 years), body mass index (BMI) was greater (27.1 vs 26.4 kg/m2), serum sodium was higher (137 vs 136 mmol/L) and patients were more likely to be white (p<0.0001). Only ethnicity was significantly different when comparing the SWLU cohort with the national NHSBT population. There was no significant difference in the indication for transplant.

Table 1

Summary of adult elective first ever registrations for a liver only transplant: 1 January 2006–31 December 2017

Post-listing survival

Between 1 January 2006 and 31st December 2017, 8521 patients ≥18 years were registered for a first liver only transplant in the UK. A total of 29 registrations were excluded from the analysis because risk factors used to describe the patients’ survival experience were missing. Of the remaining 8492 patients, 215 patients were registered at the SWLU. The risk-adjusted 1-year, 5-year and 10-year survival outcome for the SWLU cohort and the published data on the current seven UK transplant centres are presented (figure 1, table 2). The 1-year survival post-listing for first liver only transplant at the SWLU is 86% (95% CI 82% to 89%), compared with 83% (95% CI 82% to 84%), an average of the other seven UK transplant centres (figure 1, table 2). The 5-year and 10-year post-listing outcomes were 75% (95% CI 69% to 80%) and 67% (95% CI 58% to 73%), respectively, which is comparable with the seven UK transplant centres (figure 1, table 2; 10-year graph not shown).

Table 2

Risk-adjusted 1-year, 5-year and 10-year post-listing and risk-adjusted 1-year and 5-year post-transplantation patient survival rates for adult* elective first liver only registrations in the UK

Figure 1

Risk-adjusted post-listing and post-transplantation survival rates comparing the South West Liver Unit (SWLU) with the seven UK transplant centres.

Post-transplant survival

Between 1 January 2006 and 31 December 2017, 6579 patients ≥18 years underwent a first liver only deceased donor transplantation in the UK. Transplants were excluded from the analysis if they were auxiliary or if survival information or risk factors were missing, accounting for 439 patients from the 1-year cohort and 150 patients from the 5-year cohort. Of those remaining, 6140 and 3124 patients were included in the risk-adjusted 1-year and 5-year survival post-transplantation comparisons, respectively.

Waiting time and donor characteristics

Donor and transplant demographic data comparing the SWLU, KCH and nationally are shown in table 3. There were no statistically significant differences in donor type (donation after cardiac death and donation after brain stem death) and use of whole liver or split liver grafts between the SWLU and KCH or nationally. The median time to transplantation from listing was longer for SWLU than the national population (156 vs 75 days; p<0.0001) but comparable with the rest of the King’s population (137 days, p=0.11).

Table 3

Summary of donor and transplant characteristics for adult elective first ever liver only deceased donor transplants: 1 January 2006–31 December 2017

For 1-year post-transplant survival, 172 patients were registered at the SWLU, which represents 2.8% of all liver transplants within our time frame. For 5-year post-transplant survival, 84 patients were registered at the SWLU, representing 2.7% of all liver transplants. The risk-adjusted 1-year and 5-year post-transplant survival outcome for SWLU patients were compared with the seven UK transplant centres. The risk-adjusted 1-year and 5-year post-transplant survival at the SWLU is 94.9% (95% CI 89.7 to 97.4) and 84.4% (95% CI 71.9 to 91.4), respectively, which is comparable with the seven UK transplant centres (figure 1, table 2).

Discussion

The increasing burden of CLD and the delivery of equitable patient-centred healthcare services is a national priority.5 Patients with advanced liver disease complicated by decompensation or hepatocellular carcinoma have high mortality and the only curative option is often liver transplantation. With the rising prevalence of liver disease, the number of patients who could benefit from liver transplantation continues to increase.

The UK has seven established liver transplant centres to serve the whole population, but the geographical distribution is not uniform with none near the SW Peninsula.8 The transplant assessment, and subsequent pre-transplant and post-transplant care, involves close and intensive collaboration between the patient and the transplant unit often involving numerous patient visits. In remote areas such as the SW, patients are required to travel great distances at a time of serious illness. In addition to placing a considerable physical, emotional and financial burden on the patient and their support network, longer journey times reduce the likelihood of receiving a liver transplant in the UK.7

Our review of post-transplant survival using the standard NHSBT data sets reported by all the transplant units has demonstrated that the short-term, medium-term and long-term outcomes achieved using our networked and devolved model of care are good. Risk-adjusted post-listing survival at 1, 5 and 10 years and the risk-adjusted post-transplant survival at 1 and 5 years for patients assessed and managed at the SWLU are comparable with the seven established transplant centres within the UK. This data provides assurance that the quality of care delivered by the SWLU, both in the period from listing to liver transplantation and in the period after transplantation, is safe and does not compromise patient clinical outcomes.

The SWLU cohort undergoing transplant assessment and both pre-transplant and post-transplant care is comparable with the national NHSBT population for both liver disease aetiology and severity with ethnic differences reflecting regional population characteristics. Even though the waiting times are longer than the national average, the time to transplantation from listing is similar between the SWLU and KCH indicating that once listed patients at the SWLU have a similar likelihood of receiving a transplant. The significant disparity in waiting times between liver transplant units is likely to be addressed with the recent move towards a national liver offering scheme.10

The devolved care model between the SWLU and KCH established in 2004 has allowed the delivery of transplant assessment plus pre-transplant and post-transplant care within the SW Peninsula for over 10 years. In that time, the clinical teams and specialist services across all parts of the network have grown and developed, and the networking arrangements have matured and increased in their scope. The adoption of modern communication platforms has vastly improved the remote participation and contribution to multidisciplinary team discussions for listing patients and made sharing of patient imaging and pathology straightforward. This means that many aspects of our networking arrangements could now be replicated in other areas in a much shorter time frame. Belfast has developed a similar devolved model of care with KCH to improve access to liver transplant service for patients living in Northern Ireland and report comparable long-term outcomes to the SWLU and existing liver transplant units (unpublished data). This provides further assurance that a devolved, networked care model can have broad applicability.

While we did not formally assess patient satisfaction in this study, a recent paper reported high levels of patient satisfaction with care provided closer to home using a less devolved hub and spoke model.9 The numbers of patients being transplanted each year continues to rise, and this together with the good survival rates means that the pool of patients needing assessment and long-term post-transplant care is growing rapidly. High quality patient-centred care delivered close to the patient is needed. Our data supports devolution of transplant assessment, pre-tranplant and post-transplant care to appropriately staffed and trained regional centres as a viable model for service delivery that could be replicated in other areas of the UK where access to transplant services is not easy. Care, delivered locally, supports patients and their families close to home during a time of major illness. It helps alleviate many concerns surrounding the physical and financial consequences of long travel distances. Finally, the continuing drive to increase organ donation and the consequent rise in liver transplant numbers means that there is also opportunity to increase the number of liver transplant centres to better meet patient needs. Centres able to demonstrate good transplant outcomes within a devolved network model of care will be well placed to develop into transplant units in the future.

Significance of this study

What is already known about this subject?

  • Devolving responsibility for liver transplant assessment and post-transplant care to a non-transplanting regional liver unit is a new model for patient-centred care developed for the South West Peninsula. However, there remain concerns that quality of care and patient outcomes might be adversely affected and to date the long-term clinical outcomes from a devolved model of care have not been described.

What are the new findings?

  • The risk adjusted post-listing and post-transplant survival rates for patients cared for by the South West Liver Unit at 1, 5 and 10 years are as good as current transplanting centres.

How might it impact on clinical practice in the foreseeable future?

  • A devolved model of care for pre-transplant and post-transplant care can improve ease of access for patients while providing equivalent outcomes to existing transplant units.

Acknowledgments

We would like to thank the clinical teams at both the SWLU and the Institute of Liver Studies at King’s College Hospital for their ongoing support.

References

View Abstract

Footnotes

  • Contributors BCN, AS, KR and MEC completed the data collection and write-up of the manuscript. RT completed the data analysis. LV, NH and VA helped outline the scope of the project and provided key input into the write-up. BCN is nominated as the guarantor of the manuscript.

  • Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

  • Competing interests None declared.

  • Patient consent for publication Not required.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data availability statement Data are available upon reasonable request. This includes the 1-year, 5-year and 10-year post-listing data and the 1-year and 5-year post-transplant outcome data as provided by NHSBT. Raw data are not available due to confidentiality. Applications should be directed to NHSBT.

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