Patients who undergo liver transplantation at age 60 or above have 1-year and 5-year survival rates similar to those of younger patients and they experience fewer episodes of rejection. These findings are published in a new study in the October issue of Liver Transplantation, a journal published by John Wiley & Sons. The article is also available online via Wiley Interscience http://www.interscience.wiley.com/journal/livertransplantion.
Though more and more patients are being listed for liver transplantation, the number of available organs has not increased. As a result, transplant centers have sought to reevaluate patient selection critieria to optimize survival outcomes and organ allocation. Older patients have long been considered high-risk recipients, because they may have other conditions and diseases alongside their liver problem, and because they have increased mortality risk overall. However, older patients have softer immune systems, which might reject transplants less often, leading to better outcomes.
Researchers, led by Timothy Cross of Kings College Hospital in London, set out to retrospectively examine the transplant outcomes of older patients compared to younger ones. They included 416 patients transplanted at Kings College between 1988 and 2003, dividing them into three groups according to age: Group 1 included 77 patients over age 65. Group 2 included 137 patients between 60 and 64 years old. And group 3 included 202 patients 18-59 years old. Each patient was regularly examined post-transplant for signs of rejection.
The researchers found that survival rates were very similar among all of the age groups. After 1-year, survival was 82 percent for patients over 65, 86 percent for patients 60-64 years old, and 83 percent for patients under 60. After 5 years, the survival rates were 73 percent, 80 percent and 78 percent respectively (these differences were not statistically significant). Notably, there was a significant difference in the number of rejection episodes between the three groups, with most occurring in the youngest group of patients.
The researchers theorized that the strong survival rates among older patients might be due to a more rigorous assessment of co-morbidities, a higher proportion of patients with primary biliary cirrhosis and lower mean MELD scores. The older patient cohorts may reflect a selection bias of patients who are deemed likely to have a good outcome from liver transplantation despite their age, the authors report.
Among patients who did not survive, cardiovascular causes were most common for patients under 65, while malignancy and sepsis were most common among patients over 65. The researchers theorized that age-related immune system weakness led to less rejection, while at the same time putting the transplant recipients at risk for infection and cancer.
While the study was limited by the fact that all patients were from one medical center, and they were not etiology matched, the results strongly suggest that liver transplantation should not be denied from older recipients on the basis of age alone, the authors conclude. Based on their lower rejection rates and excellent graft survival, they might benefit from strategies geared towards immunosuppression withdrawal and tolerance induction. However long-term follow up of these patients is warranted.
In an accompanying editorial, Ronald Busuttil and Gerald Lipshutz suggest that the data will add important information to the debate on who can and should undergo liver transplantation. While age should not be a sole criterion, they add, unless there is growth in the number of donor livers, there will continue to be debate about rationing and donor/recipient matching for this limited resource.
|Contact: Amy Molnar|
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