Cost-effectiveness of liver transplantations--how to apply the results in resource allocation

Temporal trends in early clinical outcomes and health care resource utilization for liver transplantation in the United States

INTRODUCTION

Procedures such as liver transplantation, which entail large costs while benefiting only a small percentage of the population, are being increasingly scrutinized by third-party payors. The purpose of our study was to conduct a longitudinal analysis of the early clinical outcomes and health care resource utilization for liver transplantation in the United States.

METHODS

The Nationwide Inpatient Sample database was used to conduct a longitudinal analysis of the clinical outcome and resource utilization data for liver transplantation procedures in adult recipients performed in the United States over three time periods (Period I: 1988-1993; Period II: 1994-1998: Period III: 1999-2003).

RESULTS

Compared to Period I, adult liver transplant recipients were more likely to be male, older, and non-White in Period III. Recipients were more likely to have at least one major comorbidity preoperatively than in Period I. The in-hospital mortality rate after liver transplantation decreased significantly from Period I to Period III, but the major intraoperative and postoperative complication rates increased over the same time period. Mean length of hospital stay decreased over the 15-year period, but the percentage of patients with a non-routine discharge status increased.

CONCLUSION

Our findings indicate that the rate of postoperative complications and non-routine discharges after liver transplantation is increasing. However, these negative changes in the cost-outcomes relationship for liver transplantation are balanced by improving postoperative survival rates and reductions in the length of hospital stay.

A methodological framework for optimally reorganizing liver transplant regions

BACKGROUND

The United States is divided currently into 11 transplant regions, which vary in area and number of organ procurement organizations (OPOs). Region size affects organ travel time and organ viability at transplant.

PURPOSE

To develop a methodologic framework for determining optimal configurations of regions maximizing transplant allocation efficiency and geographic parity.

METHODS

An integer program was designed to maximize a weighted combination of 2 objectives: 1) intraregional transplants, 2) geographic parity-maximizing the lowest intraregional transplant rate across all OPOs. Two classes of functions relating liver travel time to liver viability were also examined as part of the sensitivity analyses.

RESULTS

Preliminary results indicate that reorganizing regions, while constraining their number to 11, resulted in up to 17 additional transplants/year depending on the travel-viability function; when not constrained, it resulted in up to 18/year of increase.

CONCLUSION

Our analysis indicates that liver transplantation may benefit through region reorganization. The analytic method developed here should be applicable to other organs and sets of organs.

Comparing quality of life following liver transplantation for Laennec's versus non-Laennec's patients

The overall success of orthotopic liver transplantation (OLTX) includes not only survival, but quality of life (QOL) as well. We studied one controversial group of OLTX recipients, patients transplanted for alcoholic liver disease (Laennec's), to determine if their post-OLTX QOL was similar to that of patients transplanted for non-alcoholic liver disease (non-Laennec's). Over a 10-yr period, patients undergoing OLTX at our institution were asked to complete a QOL questionnaire addressing a wide range of topics from demographics and employment to symptom distress/frequency, activities of daily living, and effect of loss of health on daily life. Twenty-four Laennec's and 100 non-Laennec's OLTX recipients completed the questionnaire at both their 2- and 5-yr follow-up visits at our institution. Both groups were well-matched in age, race, and patient location status at the time of OLTX. No significant differences could be detected between Laennec's and non-Laennec's scores regarding overall QOL, including one's ability to function, health perception, and self-perception at 2 and 5 years post-OLTX, and between 2 and 5 years post-OLTX. Although not between groups, a significant difference was noted regarding patients' satisfaction with life, with less satisfaction reported at the 5-yr versus the 2-yr time point post-OLTX. Rates of current/recent employment between both groups were also similar at 2 years post-OLTX, and again at 5 years post-OLTX. We conclude that overall QOL and employment levels appear similar between patients transplanted for alcoholic and non-alcoholic liver disease. This similarity appears to extend to 5 years post-OLTX.

Cytomegalovirus immune globulin after liver transplantation: a cost-effectiveness analysis

OBJECTIVE

Cytomegalovirus (CMV) immune globulin (CMVIG) has been shown to significantly reduce severe CMV-associated disease complicating orthotopic liver transplant (OLT). We evaluated the economic impact of severe CMV-associated disease and calculated the marginal cost-effectiveness (C/E) of routine prophylaxis with CMVIG after OLT.

DESIGN

C/E analysis.

SETTING

Four teaching hospitals in Boston.

PATIENTS

Patients who underwent OLT from January 1988 through June 1990.

MEASUREMENTS

We gathered actual cost data of hospital care for patients enrolled in a clinical trial of CMVIG prophylaxis in OLT. We calculated average outpatient expenses from a separate group of patients undergoing OLT and developed a regression model to estimate costs during the first year post-transplant (R2 = 0.77). Based on this model, we calculated variable costs (in 1999 US dollars) for all patients in the randomized trial. From the published literature we obtained the probability of CMV outcomes and of long-term survival after OLT. We then developed a decision analytical model to determine an incremental C/E ratio, using a Markov simulation to estimate long-term survival and long-term costs. We discounted costs and life-years at 3% and 5% per yr.

RESULTS

Based on the efficacy rate of 54% in the controlled trial, we estimate that CMVIG will increase life expectancy by 0.65 discounted years at an additional cost of $11,600, providing a marginal C/E ratio of $17,900/yr life saved. Examining the confidence limits of efficacy, we estimate that CMVIG will have a marginal C/E ratio of $66,200 gained/yr at an efficacy of 11% and $14,000 gained/yr at an efficacy of 83%.

CONCLUSION

After OLT, prophylactic CMVIG has an incremental C/E ratio comparable to that of other well-accepted medical therapies and should be used routinely in these patients.

Cost-effectiveness analysis of alternative factor VIII products in treatment of haemophilia A

Manufactured factor VIII (FVIII) concentrates of varying purity are available for managing patients with haemophilia A. This study is a cost-effectiveness analysis of ultra-high purity and recombinant (UHP/R) FVIII products relative to intermediate and very-high purity (IP/VHP) preparations. Because the societal (including research and development) costs of FVIII products are unknown and product prices vary with market conditions, we conducted the analysis with treatment cost as a variable quantity. We estimated the largest price premium that could be paid for a UHP/R concentrate relative to an IP/VHP concentrate such that the UHP/R product is the more cost-effective preparation. In the analysis haemophilic patients were assumed to be seropositive for human immunodeficiency virus, seropositive for hepatitis C (HCV), or at risk for seroconversion of hepatitis A (HAV) or hepatitis B (HBV). The results showed that the maximum cost-effective UHP/R price premium is essentially zero if the patient is only at risk of HAV or HBV infection, positive but small for the base-case HCV+ patient, and positive and large for the base-case HIV+ patient having a short life expectancy. Thus UHP/R preparations are not uniformly more cost-effective than IP/VHP products across the spectrum of haemophilic patients' health problems, and the relative cost-effectiveness of the two classes of prepared FVIII products is sensitive to product prices. The methodology employed here can be used in other circumstances where multiple treatments exist for illnesses for which there are significant multiple comorbidities or health risks.

Liver transplantation for primary biliary cirrhosis and primary sclerosing cholangitis: predicting outcomes with natural history models

In patients with primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC), risk score models that reflect disease severity have been developed and can serve as an objective measurement to assess and evaluate the effect of the severity of liver disease on the outcome of liver transplantation. Thus, using the established Mayo risk scores for PBC and PSC, one not only can estimate survival for the individual patient but can measure disease activity as well. Indeed, several studies have suggested that the optimal timing of liver transplantation with use of the Mayo PBC model may be an important tool to improve survival, decrease morbidity, and decrease overall related costs. Likewise, studies in patients with PSC have yielded similar results. This review explores how prognostic mathematical survival models for PBC and PSC might be applied to individual patients in need of liver transplantation. The following question is addressed: How can the timing of liver transplantation be optimized to increase survival, decrease postoperative morbidity, and ultimately, decrease the overall resource utilization involved in this procedure?

Effect of orthotopic liver transplantation on employment and health status

Employment, functional status, health status, and prevalence of anxiety and depression were assessed in patients who had undergone orthotopic liver transplantation at Duke University from 1984 to 1993 to identify social and economic factors that might influence return to work after liver transplantation. Patients were asked to complete mailed questionnaires. A transplant nurse coordinator assigned patients a Karnofsky score, unaware of the questionnaire responses. The response rate was 71% (52 of 72 patients). The median age of the post-liver transplantation patients was 49 years. Median years of education were 13. Sixty-five percent of patients were male. Sixty percent of patients were employed posttransplantation. Employed and unemployed posttransplantation patients showed no significant difference in age, education, gender, marital status, race, family coping skills, or cause of liver disease. Return to work after transplantation did not correlate with socioeconomic status or spouse's employment. Posttransplantation return to work was highly correlated with pretransplant employment (P < .0005). The prevalence of anxiety and depression, assessed by the Hospital Anxiety and Depression Scale (HAD), was 9% and was no different in the employed or unemployed patients. Health status, as measured by Karnofsky score, was excellent; all patients received Karnofsky scores > or = 80%. Health perceptions were compared in employed versus unemployed posttransplantation patients with the SF-36, a 36-item short form survey developed by the investigators of the Medical Outcome Study. This revealed significantly different values in the subscale, physical functioning, with a mean score of 70.6 in the employed and a mean score of 48.4 in the unemployed posttransplantation patients (P = .004) and role-physical with a mean score of 61.8 in the employed and a mean score of 27.6 in the unemployed posttransplantation patients (P = .005). Eighty percent of patients not returning to work cited "problems with their health" as their major obstacle to employment. Although objective health status was good to excellent in all patients after transplantation, patients perceived that their health status was poor, with the lowest scores observed in unemployed posttransplantation patients.