Serum Cholesterol Changes in Long-Term Survivors of Liver Transplantation: A Comparison Between Cyclosporine and Tacrolimus Therapy Ramón Charco,* Carme Cantarell, Victor Vargas,* Luis Capdevila, Jose Luis Lázaro,* Ernest Hidalgo,* Enrique Murio,* and Carlos Margarit* The aim of this study was to compare the longterm effect of tacrolimus and cyclosporine therapies on serum cholesterol levels in liver transplant recipients. We retrospectively studied 127 consecutive adult liver transplant recipients who survived for at least 1 year after transplantation. Basal immunosuppression consisted of cyclosporine plus prednisone in 100 patients and tacrolimus plus prednisone in 27 patients. was defined as a fasting serum cholesterol level greater than 220 mg/dl. Mean follow-up was 39 months. No statistical significance was found between cyclosporine- and tacrolimus-treated patients regarding age, sex, diagnosis, and previous cholesterol levels; both groups were similar. Significantly more tacrolimus-treated patients were steroid free in the first and second year of follow-up (tacrolimus, 37% and 63%; cyclosporine, 13% and 32%, respectively; P F.01). In the third year of follow-up, this difference was not significant (77% v 56%). The overall incidence of hypercholesterolemia was 34.6% (44 patients). At the end of the study, hypercholesterolemia was found in 24 of 51 and 14 of 70 patients with and without steroids, respectively (P F.002). Also, mean cholesterol levels were 224 70 and 191 48 mg/dl before and after steroid withdrawal, respectively, P F.001. was found in 43.7% of the patients during cyclosporine plus prednisone therapy compared with 46.1% of the patients during tacrolimus plus prednisone therapy (P F.9). Greater mean cholesterol levels were found in the cyclosporine group, particularly in the second and third years of follow-up (P F.01). was found in 22% of the patients during cyclosporine monotherapy compared with 15% during tacrolimus monotherapy (P F.5). No differences were found in mean cholesterol levels during follow-up when both monotherapy groups were compared. In conclusion, a lower incidence of hypercholesterolemia was achieved in tacrolimus-treated patients, mainly when steroids were still part of the immunosuppressive treatment. Copyright 1999 by the American Association for the Study of Liver Diseases From the *Liver Transplantation Unit and the Department of Nephrology, Hospital General Universitario Vall d Hebron, Universidad Autónoma de Barcelona, Spain. Address reprint requests to Ramón Charco, MD, Liver Transplantation Unit, Hospital General Universitario Vall d Hebron, Paseo Vall d Hebron 119-129, 08035 Barcelona, Spain. Copyright 1999 by the American Association for the Study of Liver Diseases 1074-3022/99/0503-0007$3.00/0 D espite improved survival of liver transplant recipients, long-term complications of chronic immunosuppressive therapy continue to be a great source of morbidity. 1 Hyperlipidemia is recognized as a common complication after kidney and heart transplantation, 2,3 but the natural history of posttransplantation hyperlipidemia after orthotopic liver transplantation has been less well described. The initial report by Muñozetal 4 showed that mean cholesterol levels increased after liver transplantation and appeared to be related to blood cyclosporine A levels. Because no studies have been performed that actually showed a survival disadvantage for transplant recipients with hyperlipidemia or hypercholesterolemia, clinicians have been reluctant to treat these patients. Conversely, compared with cyclosporine, tacrolimus therapy seems to be associated with less alteration of cholesterol metabolism. 5 However, to date, a controlled randomized study of the long-term influence of tacrolimus- or cyclosporine-based therapy on cholesterol metabolism is lacking. The aim of this study is to compare the longterm effect of tacrolimus and cyclosporine as basal immunosuppressive drugs on serum cholesterol levels in liver transplant recipients. Material and Methods We retrospectively studied 127 consecutive adult liver transplant recipients who underwent transplantation 204 Liver Transplantation and Surgery, Vol 5, No 3 (May), 1999: pp 204-208
Cholesterol Changes After Liver Transplantation 205 between January 1989 and July 1996 who survived for at least 1 year after liver transplantation. Basal immunosuppression consisted of cyclosporine and prednisone in 100 patients and tacrolimus and prednisone in 27 patients. During follow-up, 24 patients were switched to tacrolimus therapy after cyclosporine-based immunosuppression failed. Mean follow-up was 39 months (range, 12 to 96 months). Immunosuppression Cyclosporine therapy. The cyclosporine immunosuppression protocol was changed during the study period. The first 40 patients were maintained by cyclosporine (Sandimmune, Novartis, Basel) and prednisone. Induction therapy consisted of 1 g of methylprednisolone intravenously before revascularization, followed by prednisone, 200 mg/d, decreasing to 20 mg/d over 6 days. Cyclosporine was begun in the postoperative period at 2 mg/kg/d by continuous intravenous infusion, with the dose increasing to a steady-state level of 300 to 350 ng/ml, determined by enzyme immunoassay technique during the first week. The remaining patients were maintained by a new oral microemulsion formulation of cyclosporine (Sandimmune Neoral, Novartis, Basel) and prednisone. Cyclosporine Neoral was begun in the postoperative period at 10 mg/kg/d by nasogastric probe, with the dose increasing to achieve a trough level of 250 to 350 ng/ml, determined by enzyme immunoassay technique during the first week. Tacrolimus therapy. Tacrolimus was always started in the postoperative period at 0.05 mg/kg twice daily by nasogastric probe. Dosage adjustments were based on monitoring serum tacrolimus levels to achieve a 12-hour trough level of 5 to 20 ng/ml, determined by monoclonal antibody technique. The steroid regimen was the same as in the cyclosporine group. Steroid withdrawal. During follow-up, prednisone was tapered from 20 mg/d over 6 days after liver transplantation to a minimum dose in both groups for approximately the following 3 months and was discontinued in all patients with normal biochemical parameters or in patients with allograft dysfunction caused by hepatitis C recurrence proved by biopsy. The minimum dosage of prednisone was administered to patients in whom steroids could not be discontinued in the first months, with the dosage tapered until complete withdrawal in the following months. Rejection therapy. Acute rejection episodes were treated in both groups with a 3-day bolus course of1gof methylprednisolone. If rejection persisted, a 14-day course of 5 mg/d of OKT3 was administered, mainly in cyclosporine-treated patients when tacrolimus was not available. Protocol for Conversion Indications for conversion to tacrolimus were steroidresistant rejection, chronic rejection, duct damage in the context of cholestasic hepatitis C virus recurrence, and repeated episodes of acute rejection in 1 patient, with malabsorption of cyclosporine (Sandimmune, classic formulation). Tacrolimus was always started orally after withdrawal of the final dose of cyclosporine. Initial dosage was calculated at 0.05 mg/kg twice daily. Dosage adjustments were based on monitoring serum tacrolimus levels to achieve a 12-hour trough level of 5 to 20 ng/ml and also by adjustment according to clinical and biochemical parameters. Patients converted to tacrolimus were included in the tacrolimus group after 1 year of conversion. was defined as a fasting serum cholesterol level greater than 220 mg/dl, determined in routine transplant laboratories. Normal range was 130 to 220 mg/dl. Statistical Analysis Comparisons of steroid-free patients between the cyclosporine and tacrolimus groups during follow-up and hypercholesterolemia between different treatment groups were analyzed using the chi-squared test. Cholesterol levels were analyzed using the Student s t-test. Mean cholesterol levels before and after steroid withdrawal were analyzed using paired t-test. The difference was considered statistically significant for P less than.05. Data are shown as mean values standard deviation. Results No statistical significance was found between cyclosporine- and tacrolimus-treated patients regarding age, sex, diagnosis, and previous cholesterol levels; both groups were similar (Table 1). Five patients died during follow-up. At the end of the study, 70 patients were steroid free. Significantly more tacrolimus-treated patients were steroid free in the first and second years of follow-up (tacrolimus, 37% and 63%; cyclosporine, 13% and 32%, respectively; P.01). In the third year of followup, this difference was not significant (77% v 56%). Cholesterol Changes During the study, the overall incidence of hypercholesterolemia was 34.6% (44 patients). At the end of the study, hypercholesterolemia was found in 24 of 51 and 7 of 70 patients with and without steroids, respectively (P.002). Furthermore, mean cholesterol levels were 227 73 and 191 44 mg/dl in
206 Charco et al Table 1. Patient Characteristics Cyclosporine A Tacrolimus P No. of patients 100 27 Age (yr)* 48 11.1 52.2 11.6 NS Men/Women 67/33 17/10 NS Mean pretransplant SCH (mg/dl)* 156 31 160 23 NS Original disease NS Postnecrotic cirrhosis 40 12 HCC/HCV ( ) 20 6 Cholestasic diseases 6 2 Alcoholic cirrhosis 19 4 Retransplantation 10 2 Others 5 1 Abbreviations: SCH, serum cholesterol; NS, not significant; HCC, hepatocellular carcinoma; HCV, hepatitis C virus. *Mean standard deviation. patients with and without steroids, respectively (P.01). In all patients in whom steroids were stopped, mean cholesterol levels were 224 70 and 191 48 mg/dl before and after steroid withdrawal, respectively (P.001). The mean cholesterol levels of 50 cyclosporine-treated patients were 224 60 mg/dl before steroid withdrawal compared with 192 46 mg/dl after steroid withdrawal (P.005). In contrast, no statistical differences were found in 20 tacrolimus-treated patients when mean cholesterol levels before and after steroid withdrawal were compared (222 98 v 190 56 mg/dl, respectively; P.2). was found in 18 of 38 patients (47.3%) during cyclosporine and prednisone therapy compared with 6 of 13 patients (46.1%) during tacrolimus and prednisone therapy (P.9). Greater mean cholesterol levels were found in the cyclosporine group, particularly in the second and third years of follow-up (Table 2). Conversely, hypercholesterolemia was found in only 11 of 50 patients (22%) during cyclosporine monotherapy (once steroids were stopped) compared with 3 of 20 patients (15%) during tacrolimus monotherapy (P.5). No differences were found in mean cholesterol levels during follow-up Table 2. and Cholesterol Levels in Patients With Double Therapy when both groups of monotherapy were compared (Table 3). Discussion CyA P Tacrolimus P 12/38 (47%) 6/13 (46%).9 Mean SCH (mg/dl) 1st year 218.6 53.8 208.0 58.1.3 2nd year 223.3 58.0 183.0 49.1.01 3rd year 215.6 53.7 169.1 59.4.01 Abbreviations: SCH, serum cholesterol; CyA, cyclosporine A; P, prednisone. Cholesterol disorders of chronic liver diseases usually normalize after liver transplantation. However, a high percentage of transplant recipients present with hypercholesterolemia during followup. This fact, also described in heart and kidney transplantation, supports the hypothesis that immunosuppression therapy is the main culprit. 2,3 Few data exist on the natural history of hypercholesterolemia after liver transplantation. An initial report from Jefferson Medical College in 1991 found that type II hypercholesterolemia developed in 6 of 21 patients (29%) and type IV hypercholesterolemia in 5 patients. 4 Its biochemical mechanism after solid organ transplantation is unknown. Several lines of evidence, however, strongly suggest a Table 3. and Cholesterol Levels in Patients With Monotherapy CyA Monotherapy Tacrolimus Monotherapy 11/50 (22%) 3/20 (15%).5 Mean SCH (mg/dl) 1st year 183.3 54.2 223.8 55.0.1 2nd year 197.0 63.8 178.4 53.5.2 3rd year 199.8 55.9 168.7 55.5.1 Abbreviations: SCH, serum cholesterol; CyA, cyclosporine A; P, prednisone. P P
Cholesterol Changes After Liver Transplantation 207 causal relationship between serum cholesterol and blood cyclosporine levels. 3,4 Cyclosporine may interfere with bile acid synthesis, thereby decreasing cholesterol degradation, 4 or may stimulate collateral synthesis by increasing hydroxy-methylglutarylcoenzyme A (HMG-CoA) reductase activity. 4,6 To our knowledge, neither of these hypotheses has yet been proven. The introduction of tacrolimus as a new immunosuppressive drug has signified a great advance in preventing rejection, particularly in severe episodes or steroid-resistant rejection. Tacrolimus side effects are similar to those of cyclosporine, despite the fact that tacrolimus appears to exert little effect on serum cholesterol levels. 7 However, lower steroid usage for tacrolimus-treated patients typically confounds these studies. Complete withdrawal of prednisone after liver transplantation is an increasingly common practice at most transplantation centers and seems to be more successful in liver transplant recipients than those with other types of transplants. 8 The majority of studies of steroid withdrawal after liver transplantation have been conducted in pediatric transplant recipients. 9 The fact that immunologic graft loss is rare after liver transplantation, combined with the severe side effects of long-term prednisone therapy, supports steroid withdrawal in liver transplant recipients. 8,10 In our series, as in other groups, steroid withdrawal was achieved earlier and in more patients receiving tacrolimus than cyclosporine therapy. 11,12 However, other studies showed no difference in steroid withdrawal between tacrolimus- and cyclosporine-treated patients. 13 Numerous reports showed that steroid withdrawal is safe in liver transplant recipients, but its effect on metabolic complications has been variable. 9,10,14,15 The low incidence of hypercholesterolemia and low mean cholesterol levels in our patients after prednisone was discontinued provide strong evidence that prednisone is a major causative agent in this metabolic complication. Although differences were only statistically significant in cyclosporinetreated patients, more low mean cholesterol levels were also found in the tacrolimus-treated patients after steroid withdrawal. Several reports, mainly of kidney transplantation, have found that tacrolimus-based immunosuppression reduces cholesterol levels more than cyclosporine-based regimens. 16,17 This feature, also proved in our patients, was found mainly when steroids formed part of the double therapy. Although the differences in hypercholesterolemia were not statistically significant, greater mean cholesterol levels were found in cyclosporine plus prednisone treated patients compared with those receiving tacrolimus plus prednisone. After steroids were stopped completely, the cyclosporine and tacrolimus groups showed similar cholesterol levels. Although tacrolimus seems to exert little effect on serum cholesterol levels, our results suggest that the main contributor to hypercholesterolemia was steroids. Because the serum cyclosporine or tacrolimus levels required to prevent rejection decrease progressively over time, they could have a role in reducing cholesterol levels. Despite certain limitations of a retrospective study and differences in the number of patients in each treatment group, we can conclude that a lower incidence of hypercholesterolemia was achieved in tacrolimus-treated patients, particularly when steroids still formed part of the immunosuppressive therapy. We recommend steroid withdrawal as soon as possible from the immunosuppressive treatment because low mean cholesterol levels will be achieved. Acknowledgment The authors thank Christine O Hara for useful manuscript corrections. References 1. Stegall MD, Everson G, Schroter G, Bilir B, Karrer F, Kam I. Metabolic complications after liver transplantation: Diabetes, hypercholesterolemia, hypertension and obesity. Transplantation 1995;60:1057-1060. 2. Hricik DE, Mayes JT, Schulak JA. Independent effects of cyclosporine and prednisone on posttransplant hypercholesterolemia. Am J Kidney Dis 1991;18:353-358. 3. Ong CS, Pollock CA, Caterson RJ, Mahony JF, Waugh DA, Ibels LS. Hyperlipidemia in renal transplant recipients: Natural history and response to treatment. Medicine 1994;73:215-223. 4. Muñoz SJ, Deems RO, Mortiz MJ, Martin P, Jarrell BE, Madrey WC. Hyperlipidemia and obesity after orthotopic liver transplantation. Transplant Proc 1991;23:1480-1483. 5. Loss M, Winkler M, Schneider A, Brinkman C, Manns M, Ringe B, et al. Influence of long-term cyclosporine or FK 506 therapy on glucose and lipid metabolism in stable liver graft recipients. Transplant Proc 1995;27:1136-1139. 6. Everson TG. Bile acid metabolism and its role in human cholesterol balance. Semin Liver Dis 1992;12:420-428. 7. Starzl TE, Fung J, Jordan M, Shapiro R, Tzakis A,
208 Charco et al McCauley, et al. Kidney transplantation under FK 506. JAMA 1990;264:63-67. 8. Stegall M, Everson G, Schroter G, Karrer F, Bilir B, Sternberg T, et al. Prednisone withdrawal late after adult liver transplantation reduces diabetes, hypertension and hypercholesterolemia without causing graft loss. Hepatology 1997;25:173-177. 9. Margarit C, Martinez-Ibañez V, Tormo R, Infante D, Iglesias H. Maintenance immunosuppression without steroids in pediatric liver transplantation. Transplant Proc 1989;21:2230-2231. 10. Punch JD, Shieck VL, Campbell DA, Bromberg JS, Turcotte JG, Merion RM. Corticosteroid withdrawal after liver transplantation. Surgery 1995;118:783-788. 11. US Multicenter FK 506 Liver Study Group. A comparison of tacrolimus (FK 506) and cyclosporine for immunosuppression in liver transplantation. N Engl J Med 1994;331: 1110-1115. 12. Jindal RM, Popescu I, Emre S, Schwartz ME, Boccagni P, Meneses P, et al. Serum lipid changes in liver transplant recipients in a prospective trial of cyclosporine versus FK 506. Transplantation 1994;57:1395-1398. 13. Imagawa D, Dawson S III, Holt CD, Kirk PS, Kaldas FM, Shackleton CR, et al. Hyperlipidemia after liver transplantation. Transplantation 1996;62:934-942. 14. De Carlis L, Belli LS, Rondinara GF, Alberti A, Sansalone CV, Colella G, et al. Early steroid withdrawal in liver transplant patients: Final report of a prospective randomized trial. Transplant Proc 1997;29:539-542. 15. McDiarmid SV, Farmer D, Goldstein LI, Martin P, Vargas J, Tipton JR, et al. A randomized, prospective trial of steroid withdrawal after liver transplantation. Transplantation 1995;60:1443-1450. 16. Ochai T, Ishibashi M, Fukao K, Takahasi K, Endo T, Yokoyama I, et al. Japanese multicenter studies of FK 506 in renal transplantation. Transplant Proc 1995;27: 50-53. 17. Satterthwaite R, Aswad S, Sunga V, Shidban H, Bogaard T, Asai P, et al. Incidence of new-onset hypercholesterolemia in renal transplant patients treated with FK 506 or cyclosporine. Transplantation 1998;65:446-449.