Risk factors for premature coronary heart disease after successful liver transplantation in adults

The impact of obesity on patient survival in liver transplant recipients: a meta-analysis

BACKGROUND & AIMS

It is controversial if obesity has an impact on overall survival after liver transplantation (LT). The goal of this study was to determine if obesity impacts liver transplant recipient survival. Through subgroup analysis, we also evaluated different body mass index (BMI) thresholds and the confounding effect of ascites on survival.

METHODS

A systematic literature search from 1990 until July 2013. The main outcome was to evaluate the impact of obesity on survival in adult LT recipients. Dochotomous outcomes were reported as relative risk (RR) with 95% confidence intervals (CI).

RESULTS

Thirteen studies with a total 2275 obese and 72 212 non obese patients were included in the analysis. The combined analysis showed no difference in mortality between control and increased weight patients (RR = 0.97, 95% CI [0.82, 1.13], P = 0.66) at last follow-up. Moreover, no differences in mortality were noted in subgroup analysis comparing different BMI thresholds. There was also no differences in survival when BMI was adjusted for ascites or in studies where the liver disease severity was similar. Obese patients had worse survival than nonobese patients in pooled analysis of studies which had similar causes of liver disease (RR = 0.69, 95% CI [0.52, 0.92], P = 0.01).

CONCLUSION

The results of our pools analysis suggest that BMI does not specifically impact patient survival. However, obese patients have worse survival when analysis was performed in studies whose cohorts of obese and nonobese patients had similar causes of liver disease.

Higher tacrolimus blood concentration is related to hyperlipidemia in living donor liver transplantation recipients

BACKGROUND

The arrival of tacrolimus has drastically improved AALDLT recipients' survival. However, little data of tacrolimus have been reported concerning its effects on lipid metabolism for AALDLT recipients.

AIM

Out aim was to investigate the relationship between tacrolimus blood concentration and lipid metabolism in AALDLT recipients.

METHODS

The pre and postoperative data of 77 adult patients receiving AALDLT between 2002 and December 2007 were retrospectively reviewed. The postoperative immune suppressive regimen was prednisone with tacrolimus ± mycophenolate mofetil. Prednisone was withdrawn within the first postoperative month. Blood lipids and tacrolimus concentration were detected at the first, third, and sixth month during follow-up. Episodes of acute rejection were diagnosed based on biopsy.

RESULTS

Overall prevalence of post-transplantation hyperlipidemia was 29.9% (23/77) at the sixth postoperative month. The patients were divided into two groups, the hyperlipidemia group and the ortholipidemia group. In the 23 patients with hyperlipidemia, 15 (65%) were hypercholesterolemia, five (22%) were hypertriglyceridemia, and three (13%) patients had both hypercholesterolemia and hypertriglyceridemia. In univariate analysis, only tacrolimus blood concentration at the third and sixth post-transplantation months showed significant difference (8.7 ± 2.1 vs. 6.9 ± 3.2, p = 0.013; 9.2 ± 2.7 vs. 7.3 ± 3.8, p = 0.038, respectively). In multivariate logistic analysis, only two factors appear to be risk factors, namely, tacrolimus blood concentration at the third and sixth post-transplantation months (8.7 ± 2.1 vs. 6.9 ± 3.2, p = 0.043; 9.2 ± 2.7 vs. 7.3 ± 3.8 p = 0.035, respectively).

CONCLUSIONS

Higher tacrolimus blood concentration was related to hyperlipidemia at an early postoperative period. This indicates that tacrolimus blood concentration should be controlled as low as possible in the premise that there is no risk of rejection to minimize post-transplant hyperlipidemia after AALDLT.

Cardiovascular morbidity and obesity in adult liver transplant recipients

There is a direct relationship between the grade of obesity and mortality based on the increased cardiovascular diseases, cancer, etc. However, the results of studies in renal and liver allograft recipients relating obesity to morbidity and mortality are contradictory. A retrospective cohort study of 170 patients transplanted between March 1987 and July 1997 showed obesity to be identified in 77 (45.3%) patients. During the mean follow-up of 5 years posttransplantation, 16 (9.4%) patients experienced cardiovascular complications, including 10 patients with ischemic cardiac syndromes (five acute infarctions and five angina), five patients with acute cerebrovascular accidents, and one patient with intermittent lower limbs claudication. The prevalence of obesity at 1, 3, 5, 7, and 9 years after transplantation was 58.2%, 56.9%, 60.3%, 59.5%, and 66.4%, respectively. Compared with the baseline value, the BMI was increased at 1 year posttransplantation (25.78), a significant difference. No significant differences were found between the mean BMI values of patients with and without cardiovascular diseases, or overweight and morbidly obese patients compared to the normal weight population. Among liver transplant recipients, obesity was a frequent complication after transplantation, but it was not clearly associated with increased morbidity and mortality secondary to cardiovascular disease.

Immunosuppression impact on long-term cardiovascular complications after liver transplantation

BACKGROUND

With current early transplant patient and allograft survivals nearly optimized, long-term medical complications have become a significant focus for potential improvement in patient outcomes. Cardiovascular disease and associated risk factors have been shown in renal transplant patients to be related to the pharmacologic immunosuppression employed.

OBJECTIVE

The objective of this study is to investigate at 3 years postliver transplant (OLTx) the incidence of hypertension (HTN), hyperlipidemia (HLIP), diabetes mellitus (DM), nephrotoxicity (NTX), and cardiovascular disease (MI, angioplasty, CHF, CVA, and seborth) as well as rejection in two cohorts of liver transplant recipients who received either tacrolimus (FK-506) or cyclosporine (CSA) and to analyze the consequences of these complications on mortality following transplantation.

METHODS

Eighty-seven sequential patients (CSA: n = 50, mean age 48 years, M/F 32/18; and FK-506: n = 37, mean age 45 years, M/F 22/15) who underwent OLTx between 1994 and 1998, were >/=18 years, and had a minimum of 3 years of complete follow-up were included in the analysis. All OLTx candidates over age 50, who had a history of alcoholic cirrhosis, or had a history of cardiac conditions/events underwent complete cardiac consultation including an echocardiogram with additional cardiac investigation as indicated prior to OLTx.

RESULTS

At 3 years following OLTx, the incidence of acute rejection (40% versus 19%, P < 0.05), HTN (62% versus 38%, P < 0.05), HLIP (14% versus 5%, P = 0.08), and cardiovascular disease (18% versus 0%, P < 0.001), were significantly greater for the CSA patients compared with the FK-506 patients. Eight (20%) of the CSA patients who died before 3 years had their death attributed to cardiovascular events versus none in the FK-506 group.

CONCLUSION

Compared with CSA, FK-506 was associated with significantly less rejection and a reduced incidence of HTN and cardiovascular disease.

Tacrolimus conversion improves hyperlipidemic states in stable liver transplant recipients

With improvements in surgical technique and the advent of new and more effective immunosuppressive agents, survival rates in liver transplant recipients have dramatically improved. However, hyperlipidemia frequently develops in patients administered cyclosporine-based immunosuppression long-term, although it appears to occur less often with newer, tacrolimus-based regimens. We sought to determine whether an isolated change in the baseline immunosuppressive regimen (cyclosporine to tacrolimus) would improve hyperlipidemic states in these patients. Twenty-one long-term stable liver transplant recipients with hyperlipidemia, manifested by elevated cholesterol and/or triglyceride levels, were offered conversion to tacrolimus from cyclosporine A therapy. Lipid profiles were monitored at baseline (while on cyclosporine therapy) and at 1 and 3 months after conversion to tacrolimus therapy. There were no other medication manipulations. After conversion to tacrolimus therapy, mean cholesterol levels decreased from 251 to 202 mg/dL at 1 month (P <.001) and 194 mg/dL at 3 months (P <.001). Similarly, triglyceride levels decreased from 300 to 207 mg/dL by 1 month (P =.011) and 203 mg/dL by 3 months (P <.001). There was also a statistically significant decrease for very low-density lipoprotein levels at 3 months (P =.005) and low-density lipoprotein levels at 1 and 3 months (P =.013 and P =.014, respectively). High-density lipoprotein levels did not significantly change after conversion to tacrolimus therapy. Conversion was not accompanied by adverse side effects, and patients tolerated the change well. In conclusion, simple conversion from cyclosporine to tacrolimus-based immunosuppression therapy is safe and improves posttransplantation hyperlipidemia in a subgroup of liver transplant recipients.

Increased early morbidity and mortality with acceptable long-term function in severely obese patients undergoing liver transplantation

The effect of obesity on outcomes following liver transplantation remains unclear. We reviewed our experience with 302 liver transplants in 277 patients from September 1989 to September 1996 to determine the effect of body mass on outcome. Two-hundred and seventeen transplants were performed in patients with a body mass index (BMI) < 30 kg/m2, 55 in patients with a BMI of 30-34 kg/m2 (obese), and 30 in patients with a BMI > 35 kg/m2 (severely obese). Non-weight related pre-operative demographics were similar between groups with the exception of an increased frequency of cryptogenic cirrhosis among the obese and severely obese patients. Intra-operative transfusion requirements were greater for the severely obese group (16.2 +/- 3.5 units versus 9.1 +/- 0.8 units for the non-obese, p = 0.0004), though not when normalized to body weight (0.14 +/- 0.03 units/kg versus 0.13 +/- 0.01 units/kg, p > 0.05). Post-operatively, severely obese patients had a higher rate of wound infection (20 versus 4%, p = 0.0001) and death attributed to multisystem organ failure (15 versus 2%, p = 0.0001), although overall mortality prior to discharge and total complications were not different between groups. Actual 1-yr graft survival showed a negative trend in the severely obese group (67 versus 81% for non-obese, p = 0.07), but both 3-yr graft survival and patient survival were similar to non-obese patients (p = 0.12 and 0.17, respectively by the Cox-Mantel test). Liver transplantation in severely obese patients is associated with wound infection and early death from multisystem organ failure, but has similar long-term outcomes when compared to non-obese controls.