Hepatitis C virus (HCV)-cirrhosis is the most frequent

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1 Contribution of Donor Age to the Recent Decrease in Patient Survival Among HCV-Infected Liver Transplant Recipients Marina Berenguer, 1 Martín Prieto, 1 Fernando San Juan, 2 José M. Rayón, 3 Fernando Martinez, 1 Domingo Carrasco, 1 Angel Moya, 2 Francisco Orbis, 2 José Mir, 2 and Joaquín Berenguer 1 Recurrent hepatitis occurs in the majority of patients undergoing liver transplantation for hepatitis C virus (HCV) cirrhosis, with progression to cirrhosis in up to 30% after 5 years. Based on these data, a decrease in survival can be anticipated with prolonged follow-up. Furthermore, posttransplantation HCV-fibrosis progression has been shown in recent years to increase. Our aims were (1) to describe the natural history of HCV-infected recipients, particularly to determine whether survival has decreased in recent years; (2) to compare this outcome with that observed in non HCV-infected cirrhosis controls; and (3) to determine the factors associated with disease severity and survival. Among 522 cirrhotic patients undergoing transplantation between 1991 and 2000, 283 (54%) were infected with HCV. Yearly biopsies were performed in these recipients and at 1 and 5 years in the remainder. With similar follow-up, the percentage of deaths in the HCV( ) group was significantly higher than in the HCV( ) group (37% vs. 22%, P <.001), and patient survival was lower (77%, 61%, 55% vs. 87%, 76%, 70% at 1, 5, and 7 years, respectively; P.0001). Although survival has increased in the HCV( ) group in recent years, it has significantly decreased in HCV recipients (P <.0001). The main cause of death among the latter was decompensated graft cirrhosis (n 23/105, 22%), whereas that of HCV( ) patients was infections (n 10/52, 19%). Reasons for the recent worse outcome in HCV( ) recipients include the increased donor age and stronger immunosuppression. In conclusion, patient survival is lower among HCV( ) recipients than among HCV( ) ones and has been decreasing in recent years. The aging of donors is a major contributor to this worse outcome. (HEPATOLOGY 2002;36: ) Hepatitis C virus (HCV)-cirrhosis is the most frequent diagnosis in patients undergoing liver transplantation. 1 Viral recurrence is universal, 2 with development of histologic hepatitis in the majority of patients 3,4 and progression to cirrhosis in up to 30% after 5 years. 5,6 To date, however, most series have revealed no differences in patient or graft survival compared with uninfected controls. 3-5,7 Various reasons may explain Abbreviations: HCV, hepatitis C virus; HBV, hepatitis B virus; HDV, hepatitis D virus; HCC, hepatocellular carcinoma; HAI, histologic activity index; PCR, polymerase chain reaction; OLT, liver transplantation. From the 1 HepatoGastroenterology Service, 2 Liver Transplantation and Surgery Unit, and 3 Pathology Service, Hospital Universitario La Fe, Valencia, Spain. Received January 17, 2002; accepted April 8, Address reprint requests to: Dr. Marina Berenguer, Servicio de HepatoGastroenterología, Hospital Universitario La Fe, Avenida Campanar 21, Valencia, Spain. mbhaym@teleline.es; fax: (34) Copyright 2002 by the American Association for the Study of Liver Diseases /02/ $35.00/0 doi: /jhep these supposed discrepancies, one of which is the existence of different end points when assessing the effect of HCV infection on the graft. An indirect way to assess this effect is by calculating the rate of histologic progression posttransplantation, a task easily performed in the posttransplant setting because of the multiple biopsies generally performed and, through assessment of this rate, estimating the median time to development of graft cirrhosis. In one study, this duration was estimated to be 12 years, a duration significantly shorter than that described for the immunocompetent population. 6 From these data, one can anticipate an increase in HCV-related graft loss in the near future as transplant programs reach their second decade of activity. Our center follows a strict policy of performing annual liver biopsies as per protocol in HCVinfected recipients. 5 Furthermore, the transplant program was started just a decade ago. Based on these data, we hypothesized an increase in patient mortality among HCV-infected recipients with longer follow-up. We also 202

2 HEPATOLOGY, Vol. 36, No. 1, 2002 BERENGUER ET AL. 203 hypothesized that, because of improvements in patient care and immunosuppressive strategies, this increase in mortality would not be observed in controls not infected with HCV. The aims of this study were, therefore, (1) to describe the natural history of HCV-infected liver transplant recipients, including both clinical and histological outcome; (2) to compare this outcome with that observed in cirrhotic patient controls not infected with HCV; and (3) to identify early factors associated with this outcome. Patients and Methods Table 1. Baseline Features and Clinical Evolution of 522 Cirrhotic Patients Undergoing Liver Transplantation Between 1991 and 2000 HCV-Positive (n 283) HCV-Negative (n 239) P Sex (% males) 174 (61.5) 172 (72).01 Median age, yr (range) 56 (25-67) 50 (21-66).0001 Year of transplantation (%) 24 (8.5) 34 (14) (%) 49 (17) 42 (18) (%) 67 (24) 56 (23) (%) 98 (35) 62 (26) 1999-January 2000 (%) 45 (16) 45 (19) Hepatocellular carcinoma at transplantation (%) 79 (30) 26 (11).0001 Child score.06 A (%) 58 (20) 32 (13) B (%) 139 (49) 120 (50) C (%) 86 (31) 87 (37) Induction IS* Cycl steroids (%) 20 (7) 46 (21).0001 Cycl aza steroids (%) 186 (67) 161 (73).7 Tac steroids (%) 56 (20) 9 (4).0001 Tac aza steroids (%) 7 (2.5) 2 (1).1 MMF Cycl/tac steroids (%) 10 (3.5) 3 (1).1 Rejection-related data History of rejection (%) 86 (30) 65 (29).6 Rejections/patient (range) 0 (0-2) 0 (0-3) OKT3/ATG use (%) 14 (5) 8 (4).6 Use of MP boluses (%) 64 (23) 52 (25).5 Number of MP/patient (range) 0 (0-9) 0 (0-12) Graft cirrhosis (%) 66 (23) 5 (2).0001 Re-transplantation (%) 20 (7) 15 (6.5).8 Graft loss (%) 115 (40.5) 61 (25.5).0001 Abbreviations: IS, immunosuppression; Cycl, cyclosporine; MP, methyl-prednisolone; Tac, tacrolimus. *Not available (n 22). Not available (n 35). For induction immunosuppression and/or rejection treatment. Patients. Between January 5, 1991, and January 5, 2000, 522 adult patients (99.5% white) underwent primary liver transplantation at our institution for cirrhosis; 283 (54%) of them had chronic HCV infection [anti- HCV( ); Table 1]. Eight were coinfected with hepatitis B virus (HBV), 38 had a history of significant alcohol intake, and 1 was also diagnosed with hemochromatosis. The remaining patients underwent transplantation for the following reasons: cirrhosis resulting from HBV infection [ hepatitis D virus (HDV); n 48, 9.5%], alcoholic liver disease (n 131, 25%), cholestatic diseases (n 30, 6%), cryptogenic cirrhosis (n 18, 4%), autoimmune liver disease (n 6, 1%), and hemochromatosis (n 3, 0.5%). Hepatocellular carcinoma (HCC) was present in 105 cirrhotic livers (20%), the vast majority of which were from HCV patients (Table 1). The criteria used for selecting patients with cirrhosis and a localized HCC are those proposed previously. 8 No adjuvant chemotherapy was used in these patients. While patients were on the waiting list, tumoral alcoholization and/or chemoembolization was used in 96% of the patients. HCV-infected patients did not receive pre- and/or early posttransplantation antiviral therapy. Interferon in combination with ribavirin used as treatment for recurrent hepatitis C has only recently been introduced in our center, so its impact on progression to severe disease and mortality could not be assessed. All biopsies analyzed had been performed prior to initiating any antiviral therapy. The follow-up was terminated at the time of the patient s death, at retransplantation, or at the end of the observation period (December, 2000). The date of retransplantation was used as a censoring point in the examination of graft survival. Histological Assessment. Protocol liver biopsies were performed yearly for the first 5 years in HCV-infected patients and at 1 and 5 years for other indications. Additional biopsies were performed when clinically indicated. All biopsy specimens were reviewed by a single pathologist (J.M.R.) in a blinded fashion, and only those obtained before any antiviral therapy was instituted were evaluated in this study (median, 2/patient; range, 1-6). Sections were stained routinely with hematoxylin-eosin, reticulin, and Perls and Orcein stains. When appropriate, immunostaining for hepatitis B core and B surface antigens was performed. Liver biopsies classified as hepatitis were scored evaluating both the stage of fibrosis and the degree of necroinflammatory activity, according to a slight modification of the histologic activity index (HAI) proposed by Knodell and colleagues. 5 The grade was determined by combining the HAI scores for periportal necrosis, lobular degeneration and necrosis, and portal inflammation and was defined as follows: 1 to 2, minimal; 3 to 6, mild; 7 to 10, moderate; 11 to 14, severe. The stage corresponded to the original HAI fibrosis score: 0, none; 1, fibrous portal

3 204 BERENGUER ET AL. HEPATOLOGY, July 2002 expansion; 3, bridging fibrosis; and 4, cirrhosis. Pre- and postreperfusion biopsies were routinely performed in all cases to assess the quality of the graft. Immunosuppression. Induction immunosuppression consisted of (1) standard triple therapy with cyclosporine, azathioprine, and steroids; (2) dual therapy with cyclosporine and steroids; (3) dual therapy with tacrolimus and steroids; (4) triple therapy with tacrolimus, azathioprine, and steroids; and (5) triple therapy with cyclosporine or tacrolimus, steroids, and mycophenolate mofetil (Table 1). The immunosuppression induction protocols followed at our center have changed over the years, such that, for the first 5 years of transplant activity, most of the patients received standard triple therapy (cyclosporine, azathioprine, steroids), whereas, for the last 4 years, different combinations have been used depending on study protocols (given below). Initial doses were as follows: azathioprine (1-2 mg/kg/d); methylprednisolone given intravenously with tapering of the dose from 200 to 20 mg at day 6, at which time 20 mg/day of prednisone were administered orally; cyclosporine (trough levels of ng/ml for the first month, ng/ml for the second and third months, ng/ml until the end of the first year, and approximately 100 ng/ml thereafter); tacrolimus (trough levels of 5-15 ng/ml for the first 3 months, 5-10 ng/ml thereafter); mycophenolate mofetil (1 g/12 hours). The center s policy on long-term immmunosuppression has also evolved over time. Overall, secondary drugs, including azathioprine, mycophenolate mofetil, and steroids were discontinued within the first year of transplantation. In particular, prednisone dosage was progressively decreased to 2.5 to 5 mg/d at first year postransplantation during the first 5 years of transplant activity, whereas this tapering was performed at a faster rate after Decisions regarding a change in immunosuppression depending on the graft function were not uniform throughout the study period. Nevertheless, there was a trend toward diminishing cyclosporine, tacrolimus, and corticosteroid doses in patients who had developed recurrent hepatitis C. Cytomegalovirus Prophylaxis. Ganciclovir, administered either intravenously for days or orally (1 g/8 hours for 90 days) was given under the following circumstances: (1) positive donor and negative recipient; (2) retransplantation; (3) use of monoclonal or policlonal antibodies; (4) surgery complicated with high bloodproduct requirements. Predictive Factors of HCV-Related Graft Cirrhosis and/or Survival. The following factors were analyzed as early predictors of cirrhosis: (1) demographics: age at transplantation and sex distribution; (2) pretransplantation variables: presence of HCC either known or incidental, Child-Pugh classification, history of significant alcohol consumption; (3) donor-related variables: age and sex, or sex mismatch; (4) surgical-related variables: duration of cold preservation and rewarming time, duration of intervention, number of units of packed red blood cells transfused during surgery; (5) history of acute recurrent hepatitis evidenced histologically; an initial liver biopsy was typically performed when liver enzymes rose to twice the upper limit of normality; if, in these cases, changes compatible with HCV-related acute hepatitis were present, the patient was included in the group of patients with a history of acute hepatitis C ; (6) presence of serologic markers of past HBV infection (HBcAb); (7) immunosuppression-related variables, such as induction of immunosuppression, rejection episodes and their treatment occurring within the first year posttransplantation, use of OKT3 or antithymocyte globulin (ATG; for induction immunosuppression and/or rejection treatment); and (8) year of transplantation. The same variables adding the yearly rate of HCV-related fibrosis progression 6 were used to assess their effect on patient/graft survival. The infecting genotype was not considered a potential predictive factor, because the vast majority of patients tested were 1b (97%). The viral load was not evaluated as a predictive factor, because the tests used to quantify viremia have changed substantially over the years, and correctly stored serum samples were not usually available. Retransplantation Policy. Retransplantation was considered only for patients younger than age 65 years. Moreover, among HCV-infected recipients, retransplantation was not considered if the patient had developed HCV-related cirrhosis within 1 year after transplantation. Statistical Analyses. The rate of yearly fibrosis progression was calculated for each patient as the ratio between the stage of fibrosis observed on the last available liver biopsy, before any antiviral therapy was instituted, and the years elapsed since transplantation. Categorical data were compared using a 2 test or Fisher s Exact Test when indicated. When categorical variables were ordered, comparisons were made using a 2 test for trend. Continuous variables were expressed as median and range and compared by Mann-Whitney test. The Kaplan-Meier estimator of the distribution of survival time was used to calculate patient survival over time, and cumulated probability of developing HCV-related graft cirrhosis by several host and donor variables. The log-rank test was used to compare survival distributions. Those variables with a P value of less than.1 in the univariate analysis were subsequently entered in a multivariate analysis using a stepwise forward Cox regression procedure. All statistical analyses were performed with SPSS 9.0 (SPSS Inc., Chicago, IL).

4 HEPATOLOGY, Vol. 36, No. 1, 2002 BERENGUER ET AL. 205 Table 2. Causes of Death (n 157) in HCV-Positive and HCV-Negative Transplant Recipients Results HCV-Positive (%) HCV-Negative (%) P Decompensated graft cirrhosis 23 (22) Infections 20 (19) 10 (19) 1 Cardiovascular 5 (5) 4 (8).4 Neurologic 6 (6) 3 (6) 1 Technical 8 (8) 6 (11.5).5 Tumoral recurrence 9 (8.5) 3 (6).7 De novo cancer 5 (5) 6 (11.5).1 Chronic rejection 4 (4) 4 (8).4 Perioperative 15 (14) 7 (13) 1 Other 10 (9.5) 9 (17).1 Total 105 (37) 52 (22).0001 NOTE. The deaths occurred at a median of 3 years posttransplantation. In the HCV-positive group, 64 deaths occurred within the first year posttransplantation: recurrent HCV disease (n 3), infections (n 16), cardiovascular (n 4), neurologic (n 5), technical (n 5), perioperative (n 15), tumoral recurrence (n 3), de novo cancer (n 4), chronic rejection (n 1), other (n 8). Clinical Outcome. One hundred fifty-seven (30%) of the patients died within a median follow up of 3 years (range, 0-10 years; Table 1). With similar follow-up, the percentage of deaths occurring in the HCV( ) group was significantly higher than in the HCV( ) group (37% vs. 22%, P.0001). The causes of death are summarized in Table 2. The main etiology among HCV-infected recipients was recurrence of the original disease, which is decompensated HCV-related cirrhosis (n 23/105, 22%; among them, only in 3 was the evolution compatible with the aggressive cholestatic form), whereas that of the HCV( ) group was infections (n 10/52, 19%). Besides differences in decompensated HCV-related graft cirrhosis, there were no statistically significant differences regarding the cause of death between the 2 groups. In the HCV( ) group, 3 (4.5%) of the deaths occurring within the first year posttransplantation were due to complications derived from the HCV-cirrhosis. Two of these deaths occurred very close to the first year posttransplantation (at 342 and 350 days posttransplantation). Patient and Graft Survival. Patient survival was significantly lower in the HCV( ) group than in the HCV( ) group (P.0001; Fig. 1). Graft survival was also significantly lower in HCV-infected patients than in controls (74% vs. 84% at 1 year, 56% vs. 71% at 5 years, 51% vs. 67% at 7 years; P.0004). Among HCVinfected recipients, the presence of HCC did not have an impact on the outcome, with similar patient and graft survival in those with HCC at transplantation (n 79) and those without (n 204; P.4, log-rank test). Both patient and graft survivals were significantly related to the year of transplantation, albeit with opposite trends depending on the HCV status. Although patient (data not shown) and graft survivals have increased in non HCV-infected patients in recent years, they have significantly decreased in HCV-infected recipients (Figs. 2 and 3). Natural History of Histologic Recurrent Hepatitis C: Development of HCV-Related Graft Cirrhosis. Among the 105 HCV-infected patients who died posttransplantation, 64 died within the first year, thus not reaching the first-year liver biopsy. The 3 patients dying within the first year posttransplantation from complications of HCV-graft cirrhosis had had a liver biopsy confirming the diagnosis at a time close to the first year, so they were included in the histological analysis. A liver biopsy was not obtained for the remaining patients dying during the first year posttransplantation, because the Fig. 1. Patient survival in HCVinfected and non HCV-infected liver transplant recipients. Patient survival was significantly lower in the HCV( ) group than in HCV( ) group (P.0001, log-rank test).

5 206 BERENGUER ET AL. HEPATOLOGY, July 2002 Fig. 2. Graft survival in HCV-infected recipients (n 283): effect of year of transplantation. Graft survival has significantly decreased in HCV-infected recipients in recent years (P.01, log-rank test). cause of death was absolutely unrelated to liver dysfunction or complications of graft cirrhosis. Twenty-seven additional patients were not considered for histologic assessment for the following reasons: de novo HBV infection (n 10), HCV RNA negative by polymerase chain reaction (PCR) posttransplantation on more than 2 occasions (n 2), difficulty in the histologic assessment from coincidental problems such as Budd-Chiari or biliary complications (n 7), and lack of at least 1 protocol biopsy (n 8). The histological outcome was thus assessed for a total of 189 liver transplant patients with positive HCV RNA in serum posttransplantation, without HBV coinfection, unequivocal lesions of recurrent hepatitis C, and at least 1 year of histological follow-up. In total 430 protocol liver biopsies were reviewed, corresponding to a median of 2 (range, 1-6) per patient. At the last histological assessment, the fibrosis stage was null in 56 samples (29%), 1 in 44 (23%), 3 in 27 (14%), and 4 in 62 (32%). The cumulative probability of developing HCV-related graft cirrhosis (4.5% at 1 year, 25% at 3 years, 44% at 5 years) reached 51% at 7 years posttransplantation. As with survival, the probabilitiy was significantly higher in patients undergoing transplantation recently (Fig. 4). Risk Factors Associated With Cirrhosis (Fibrosis 4). Variables associated with a higher probability of developing cirrhosis in the univariate analysis were donor age, duration of intervention, induction with tacrolimus versus cyclosporine, induction without azathioprine, OKT3/ATG use, and a history of acute hepatitis (data not shown). Only 4 of these were independently associated with the development of cirrhosis (Cox regression analy- Fig. 3. Graft survival in non HCVinfected recipients (n 239): effect of year of transplantation. Graft survival has significantly increased in non HCV-infected patients in recent years (P.003, log-rank test).

6 HEPATOLOGY, Vol. 36, No. 1, 2002 BERENGUER ET AL. 207 Table 3. Risk Factors Associated With Cirrhosis and With Patient Survival Among HCV-Infected Recipients Variable* Relative Hazard 95% Confidence Interval Associated with cirrhosis Donor age History of acute hepatitis Use of OKT3/ATG Induction with tacrolimus Associated with survival Female recipient sex Donor age Rate of HCV-related fibrosis progression* OKT3/ATG use Fig. 4. Cumulative probability of developing HCV-related graft cirrhosis: effect of year of transplantation. The cumulative probability of developing HCV-related graft cirrhosis was significantly higher among patients undergoing transplantation recently than among those undergoing transplantation in earlier cohorts (P.0001, log-rank test). sis): donor age (P.0001; Fig. 5), history of acute hepatitis (P.0001), use of OKT3/ATG (P.05), and induction with tacrolimus (P.009; Table 3). Predictive Factors of Patient Survival. Variables associated with survival in HCV-infected recipients in the univariate analysis included female recipient sex, donor age, the rate of fibrosis progression, the use of OKT3/ ATG, a history of rejection, and the number of rejection episodes (data not shown). Only 4 were independently associated with survival (Cox regression): female recipient sex (P.01), donor age (P.005), rate of HCV-related Fig. 5. Cumulative probability of developing HCV-related graft cirrhosis: effect of donor age. The probability of developing HCV-related graft cirrhosis posttransplantation in HCV-infected recipients was significantly higher among those who received an organ from a donor 60 years or older compared with those who received the organ from donors aged years. In the latter, the probability was in turn higher than that observed in those receiving the organ from a younger donor (P.0001, log-rank test). NOTE. A Cox regression procedure was used to perform this multivariate analysis. *All variables included in the analysis were binary, except for age (years) and rate of HCV-related fibrosis progression (units per year), which were continuous. fibrosis progression (P.0001), and OKT3/ATG use (P.01; Table 3). Similarly, predictors of patient survival in the 239 controls were type of induction immunosuppression, use of OKT3/ATG, number of blood units transfused, and warming ischemic time (data not shown). Only 3 were found to be independently associated with survival (Cox regression): use of OKT3/ATG, rewarming time, and type of induction immunosuppression. Evolution of Variables Over Time. In an attempt to establish the reasons for the worse outcome observed in recent years in HCV-infected recipients, we analyzed the changes in variables that have occurred with time (Table 4). The following variables have changed significantly over the years: (1) presence of HCC at transplantation, which is significantly more common in recent years; (2) Child classification, with an increase in sicker patients undergoing transplantation in recent years; (3) donor age, which has increased significantly with time; (4) surgery-related variables, which have improved with time (less duration of surgery, less need for blood transfusion, less cold ischemic and rewarming time); (5) induction immunosuppression, with an increase in the use of drugs considered more potent; (6) rejectionrelated variables, with a decrease in the number of rejection episodes and their treatment, possibly as a consequence of more potent basal immunosuppression and a shortening of the duration of both azathioprine and prednisone therapies per protocol; and (7) an earlier development of HCV-related hepatitis, including the acute and chronic phase of the disease. Discussion HCV-related hepatitis follows a course in the transplant setting more aggressive than that seen in immuno-

7 208 BERENGUER ET AL. HEPATOLOGY, July 2002 Table 4. Evolution of Several Variables Over Time in HCV-Infected Patients (n 283) Variables/Year of OLT (n 27) (n 48) (n 67) (n 97) (n 40) P Sex (% male) Age at transplantation, yr (range) 52 (30-62) 55 (25-65) 57 (31-66) 57 (32-66) 56 (28-67).05 Alcohol pre-transplantation (%) HCC at transplantation (%) Child classification (% C) Donor sex (% male) Donor age,* yr (range) 23 (15-58) 30 (9-61) 39 (13-73) 43 (13-84) 52 (16-77).0001 Donor-recipient sex mismatch (%) Cold ischemia, min (range) 290 ( ) 467 (60-830) 370 ( ) 330 ( ) 300 (45-760).001 Rewarming time, min (range) 65 (45-108) 60 (25-95) 55 (30-115) 45 (14-90) 35 (15-255).0001 Use of packed blood cells (range) 5 (1-15) 4 (0-19) 3 (0-22) 2 (0-12) 3 (0-11).0001 Surgical time, min (range) 420 ( ) 400 ( ) 315 ( ) 280 ( ) 260 ( ).0001 Induction IS Cyclosporine* (%) Tacrolimus* (%) Azathioprine (%) Mycophenolate (%) Combination IS.0001 Cyclosporine-azathioprine (%) Cyclosporine (%) Tacrolimus (%) Tacrolimus-azathioprine (%) Cyclosporine or tacrolimus/mmf (%) Rejection (%) Number rejection episodes (range) 0 (0-2) 1 (0-2) 0 (0-2) 0 (0-2) 0 (0-2).0001 Methyl-prednisolone boluses (%) Number methyl-prednisolone boluses (range) 0 (0-9) 3 (0-6) 0 (0-6) 0 (0-3) 0 (0-5).0001 OKT3/ATG use* (%) Duration prednisone, days (range) 1368 ( ) 804 ( ) 466 ( ) 325 ( ) 221 (34-466).0001 Duration azathioprine, days (range) 61 ( ) 410 ( ) 190 (29-820) 91 (4-334).0001 History of acute hepatitis* (%) Time to acute hepatitis, d (range) 190 (69-365) 119 (61-177) 120 (48-388) 78 (30-405) 52 (11-157).001 Time until F3/4, d (range) 1826 ( ) 1096 ( ) 1076 ( ) 748 ( ) 348 ( ).0001 ALT levels at 1 year post-olt, IU (range) 102 (23-286) 96 (12-358) 66 (15-546) 83 ( ) 131 (23-422).2 HBV markers (% HBcAb positivity) Abbreviations: ALT, alanine aminotransferase levels; HBcAb, antibodies against HBV core antigen; MMF, mycophenolate mofetil. *Variables independently associated with a higher probability of developing cirrhosis. compentent patients 6 not only up to the phase of cirrhosis, which may develop in as many as 30% with 5 years of follow-up, 5 but also afterwards, with a high risk of decompensation of approximately 50% in 1 year. 8 In spite of these data, hepatitis C continues to be considered a good indication for transplantation, because graft and patient survivals have been similar to those of uninfected controls in most series. 3-5,7 The main reason for these discrepancies is likely the inadequacy of follow-up to measure the full effect of recurrent HCV disease. Indeed, most studies have not followed the patients long enough to detect differences in survival. Intermediate end points, such as histological disease progression, represent a dynamic way of assessing the aggressiveness of the disease. This approach was recently applied in our series of patients in combination with a group of U.S. transplant patients. 6 We estimated, based on the rate of fibrosis progression, an expected time to graft cirrhosis of approximately 1 decade, with a faster progression observed in recent years. We hypothesized, based on these estimations, that in centers such as ours in which the transplant activity is reaching the second decade, the survival of HCV-infected patients would begin to show differences with respect to controls. Furthermore, and because fibrosis progression was shown to increase in recent years, we also hypothesized a recent decrease in patient survival. Finally, and because improvements have been made both in surgical techniques and in immunosuppression, we hypothesized that this worse outcome would not be observed in control recipients not infected with HCV. These 3 hypotheses have been confirmed in this study, and 2 main conclusions may be drawn. First, the decrease in survival in HCV-infected recipients underscores the need for better antiviral therapies. Indeed, the main cause of death in the HCV( ) group was recurrent decompensated HCV-re-

8 HEPATOLOGY, Vol. 36, No. 1, 2002 BERENGUER ET AL. 209 lated graft cirrhosis, 8 with a probability of developing cirrhosis of 44% at 5 years. This percentage is higher than that reported in earlier published data, 5 most likely reflecting the more aggressive course of recurrent hepatitis C observed in patients undergoing transplantation recently. Second, if this trend continues, and antiviral therapies do not show a positive effect, HCV-cirrhosis may become a controversial indication for liver transplantation. Because this study included only untreated patients, we could not assess the effects of antiviral regimens on the natural history of recurrent HCV. Interestingly, the presence of HCC, a finding increasingly common in patients with HCV infection, was not found to be associated with a worse outcome, probably as a result of the strict criteria applied when accepting a transplantation candidate with a tumor. Indeed, most of the patients with HCC in a cirrhotic liver were transplanted after 1995 (81%), at which time variables associated with good outcome and low-recurrence rate were already established. 9 This may explain differences from other studies, which have found an association between HCC and survival among HCVinfected recipients. 7 An understanding of the mechanisms of disease injury under these circumstances may allow for improved organ allocation and patient management. The assessment of variables associated with disease severity and/or progression constitutes an indirect approach to this understanding. We sought to establish the reasons for an aggressive progression of HCV liver damage in some but not all patients. One simple variable was consistently associated with the development of cirrhosis and poor survival: donor age (Fig. 5). The increasing age of donors may explain the worse outcome seen recently. The negative impact of increasing donor age on patient and graft survival independent of primary liver disease has been reported previously. 10 However, and interestingly, this effect was not observed among the non HCV-infected patients, a group who received marginal livers with the same frequency as the study group (data not shown), suggesting that this is detrimental only in the HCV-infected patients, an observation that may have real relevance for HCV pathogenesis. Indeed, the observation of a more rapid progression of hepatitis C in an older donor allograft is analogous to the accelerated natural history of hepatitis C after acute infection of the older nontransplant patient. 11 The mechanisms by which old age may be associated with an accelerated course of the disease are not completely understood. Several investigations in animals have shown that the proliferative response to some aggressions is reduced or delayed in older rats. 12 Alternative reasons for the worse outcome may be the use of stronger induction immunosuppression and an earlier and faster reconstitution of the immune system with withdrawal of secondary immunosuppressive drugs, such as prednisone and azathioprine, at earlier time points than was previously done (Table 4). As the immune system is reconstituted, an immune-mediated liver damage may occur, with progression to severe forms of chronic hepatitis. 13 In that sense, the fact that patients are taken off prednisone at earlier time points than before may explain in part the faster disease progression seen recently. In this study, HCVinfected patients receiving tacrolimus-based immunosuppression were more likely to experience severe graft injury than those receiving cyclosporine. However, and as has been reported by others, 4 immunosuppression induction was not associated with either patient or graft survival. Although most studies have found no differences in patient survival or disease severity in transplant recipients treated with cyclosporine-based versus tacrolimus-based regimens, indirect evidence suggests that increasing immunosuppression may worsen HCV recurrence. In that sense, tacrolimus is considered a more potent drug than cyclosporine, which in turn likely explains the reduction over time of rejection episodes and the need for antirejection therapy (Table 3). Consistent with this hypothesis is the recent finding of a deleterious effect of antiinterleukin 2 receptor antibodies in combination with mycophenolate mofetil, 2 potent immunosuppressive drugs, in the outcome of recurrent hepatitis C. 14 Prospectively randomized, controlled trials are clearly needed to address adequately the role of these regimens in the natural history of recurrent HCV disease. Some variables that have been associated with outcome in HCV-infected patients, such as viral load at transplantation 4 and cytomegalovirus disease 15 were not analyzed in this study. Others, which, although not assessed in previous studies, could potentially have a significant impact, such as alcohol consumption posttransplantation, viral load, or pretransplantation creatinine, also were not analyzed. We, however, believe that there is no reason to think that these variables have changed with time. Particularly, we have shown in a previous study including patients from both our center and the University of California, San Francisco, that viral load at transplantation has not changed over the years. 6 Similarly, there is no reason to believe that the rate of alcohol consumption following transplantation has changed over the years. Although this variable was not included in the study because of the difficulties in assessing alcohol consumption in transplant patients, serious alcohol consumption was detected in very few patients. Previous interferon therapy in the pretransplantation period may help in selecting out a group of nonresponders who are resistent to interferon. This, in turn, may play a role in posttransplantation outcome. Although this variable also

9 210 BERENGUER ET AL. HEPATOLOGY, July 2002 was not included in this study, we have previously shown that very few patients from this cohort had been treated with interferon for their hepatitis prior to transplantation. 6 Interestingly, rejection-related variables were associated with severe disease only in the subgroup of patients undergoing transplantation before 1996 (data not shown), in accordance with our previous studies. 5 The low frequency of rejection episodes and treatment with methylprednisolone boluses after that period, resulting in part from the introduction of more potent, first-line immunosuppressive drugs, may explain the lack of correlation with outcome in the overall series of patients and in those undergoing transplantation after In conclusion, the results from this study confirm previous assumptions, that is, a significant negative impact of HCV infection on both graft and patient survivals, an impact that appears to be more relevant in recent years. One simple variable, donor age, may be used to predict a worse outcome at early time points posttransplantation. The preferential use of organs from younger donors may become a strategy to improve the outcome for these patients. Alternatively, and given the shortage of organ donors, early antiviral therapy should be undertaken if treatment is shown to be effective. Finally, independent trials comparing different schedules of immunosuppression should be performed for selection of a more rational use of immunosuppression. References 1. Prieto M, Berenguer M, Rimola A, Loinaz C, Barrios C, Clemente G, Figueras J, et al. Liver transplantation in hepatitis C: a Spanish multicenter experience. Eur J Gastroenterol Hepatol 1998;10: Wright T, Donegan E, Hsu H, Ferrell L, Lake JR, Kim M, Combs C, et al. Recurrent and acquired hepatitis C viral infection in liver transplant recipients. Gastroenterology 1992;103: Gane E, Portmann B, Naoumov N, Smith HM, Underhill JA, Donaldson PT, Maertens G, et al. Long-term outcome of hepatitis C infection after liver transplantation. N Engl J Med 1996;334: Charlton M, Seaberg E, Wiesner R, Everhart J, Zetterman R, Lake J, Detre K, et al. Predictors of patient and graft survival following liver transplantation for hepatitis C. HEPATOLOGY 1998;28: Prieto M, Berenguer M, Rayón M, Córdoba J, Argüello L, Carrasco D, Garcia-Herola A, et al. High incidence of allograft cirrhosis in hepatitis C virus genotype 1b infection following transplantation: relationship with rejection episodes. HEPATOLOGY 1999;29: Berenguer M, Ferrell L, Watson J, Prieto M, Kim M, Rayon M, Cordoba J, et al. HCV-related fibrosis progression following liver transplantation: increase in recent years. J Hepatol 2000;32: Feray C, Caccamo L, Alexander GJM, Ducot B, Gugenheim J, Casanovas T, Loinaz C, et al. European Collaborative Study on factors influencing the outcome after liver transplantation for hepatitis C. Gastroenterology 1999; 117: Berenguer M, Prieto M, Rayón JM, Mora J, Pastor M, Ortiz V, Carrasco D, et al. Natural history of clinically compensated HCV-related graft cirrhosis following liver transplantation. HEPATOLOGY 2000;32: Mazzaferro V, Regalia E, Doci R, Andreola S, Pulvirenti A, Bozzetti F, Montalto F, et al. Liver transplantation for the treatment of small hepatocellular carcinomas in patients with cirrhosis. N Engl J Med 1996;334: Busquets J, Xiol X, Figueras J, Jaurrieta E, Torras J, Ramos E, Refecas A, et al. The impact of donor age on liver transplantation: influence of donor age on early liver function and on subsequent patient and graft survival. Transplantation 2001;71: Poynard T, Bedossa P, Opolon P. Natural history of liver fibrosis progression in patients with chronic hepatitis C. Lancet 1997;349: Sigal SH, Rajvanshi P, Gorla GR, Sokhi RP, Saxena R, Gebhard DR, Reid CM, et al. Partial hepatectomy-induced polyploidy attenuates hepatocyte replication and activates cell aging events. Am J Physiol 1999;276:G1260-G DiMartino V, Saurini F, Samuel D, Gigou M, Dussaix E, Reynes M, Bismuth H, et al. Long-term longitudinal study of intrahepatic hepatitis C virus replication after liver transplantation. HEPATOLOGY 1997;26: Nelson DR, Soldevila-Pico C, Reed A, Abdelmalek MF, Hemming AW, Van der Werf WJ, Howard R, et al. Anti-interleukin-2 receptor therapy in combination with mycophenolate mofetil is associated with more severe hepatitis C recurrence after liver transplantation. Liver Transplant 2001; 7: Rosen H, Chou S, Corless C, Gretch DR, Flora KD, Boudousquie A, Orloff SL, et al. Cytomegalovirus viremia. Risk factor for allograft cirrhosis after liver transplantation for hepatitis C. Transplantation 1997;64: