Survival after liver transplantation in the United Kingdom and Ireland compared with the United States

<b>Background and Aim</b>: Surgical mortality in the US is widely perceived to be superior to that in the UK. However, previous comparisons of surgical outcome in the two countries have often failed to take sufficient account of case-mix or examine long-term outcome. The standardised nature of liver transplantation practice makes it uniquely placed for undertaking reliable international comparisons of surgical outcome. The objective of this study is to undertake a risk-adjusted disease-specific comparison of both short- and long-term survival of liver transplant recipients in the UK and Ireland with that in the US. <b>Design, setting and participants</b>: Multi-centre cohort study using two high quality national databases including all adults who underwent a first single organ liver transplant in the UK and Ireland (n=5,925) and the US (n=41,866) between March 1994 and March 2005. <b>Main outcome measures</b>: Post-transplant mortality during the first 90 days, 90 days-1 year and beyond the first year, adjusted for donor and recipient characteristics. <b>Results</b>: Risk-adjusted mortality in the UK and Ireland was generally higher than in the US during the first 90 days (hazard ratio 1.17 95%CI 1.07-1.29), both for patients transplanted for acute liver failure (hazard ratio 1.27 95%CI 1.01-1.60) as well as those transplanted for chronic liver disease (hazard ratio 1.18 95% CI 1.07- 1.31). Between 90 days and 1 year post-transplantation, no statistically significant differences in overall risk- adjusted mortality were noted between the two cohorts. Survivors of the first post-transplant year in the UK and Ireland had lower overall risk-adjusted mortality than those transplanted in the US (hazard ratio 0.88 95% CI 0.81- 0.96). This difference was observed among patients transplanted for chronic liver disease (hazard ratio 0.88 95%CI 0.81-0.96) but not those transplanted for acute liver failure (hazard ratio 1.02 95%CI 0.70- 1.50). <b>Conclusions</b>: Whilst risk adjusted mortality is higher in the UK and Ireland during the first 90 days following liver transplantation, it is higher in the US among those liver transplant recipients who survived the first post- transplant year. Our results are consistent with the notion that the US has superior acute peri-operative care whereas the UK appears to provide better quality chronic care following liver transplantation surgery

The impact of serum potassium concentration on mortality after liver transplantation: a cohort multicenter study

Background: Potassium plays a key role in human metabolism in both health and disease. The impact of recipient serum potassium concentration [K] on mortality after liver transplantation has not been described previously. Methods: We assessed the effect of recipient [K] on the survival of adult first single-organ liver transplant recipients in the United Kingdom and Ireland between March 1, 1994, and February 28, 2007 (n=5942), adjusting for recipient, donor, and graft characteristics. Results: The overall risk-adjusted mortality significantly varied by [K], being higher among hyperkalemic ([K]>5.0 mmol/L) recipients (n=424, hazard ratio [HR] 1.38, 95% confidence interval [CI] 1.01-1.88) and those with [K] of 4.5-5.0 mmol/L (n=1154, HR 1.47, 95% CI 1.13-1.91), compared with hypokalemic ([K]<3.5 mmol/L) recipients (n=360). However, the excess mortality was confined to the first posttransplant year among hyperkalemic recipients (HR 1.61, 95% CI 1.10-2.35) with no significant difference thereafter (HR 1.03, 95% CI 0.62-1.73). This was also true for recipients with [K] of 4.5 to 5.0 mmol/L (≤1 year: HR 1.70, 95% CI 1.22-2.38; >1 year: HR 1.09, 95% CI 0.71-1.66). In contrast, those with [K] of 3.5 to 3.9 mmol/L (n=1518) and [K] of 4.0-4.4 mmol/L (n=2091) had similar risk-adjusted mortality at the above time points. When [K] was used as a continuous variable in the multivariable analysis, a mmol increase in [K] was associated with an increased adjusted risk of mortality of 27% (95% CI 12%-44%) at 1 year and 19% (95% CI 7%-31%) at 5 years. Conclusion: Recipient [K] is an independent predictor of death after liver transplantation. This finding could be of clinical utility in the management, risk stratification, selection, and prioritization of appropriate candidates for transplantation among patients with end-stage liver disease