Plasma total homocysteine and cardiovascular risk in patients submitted to liver transplantation

Hyperhomocysteinemia is associated with severity of cirrhosis and negative impact after liver transplantation

BACKGROUND & AIMS

Hyperhomocysteinemia constitutes an independent risk factor for thrombosis and cellular injury promoted by oxidative stress. The clinical significance of hyperhomocysteinemia in cirrhosis and outcomes post-liver transplantation is poorly documented. In this study, we aimed to determine the prevalence of hyperhomocysteinemia in cirrhosis, evaluate its association with thrombosis and severity of liver disease, and its impact on survival after liver transplantation.

METHODS

We analysed 450 patients with cirrhosis who received a liver transplant between 2001 and 2010. Data were recovered from medical charts and homocysteine serum levels were determined before liver transplantation in all patients.

RESULTS

Median age was 53 years (range, 18-72 years) and 308 patients were males (68%). Cirrhosis aetiology was hepatitis C (37%), autoimmune liver disease (22%), alcohol (16%) and others (25%). The median homocysteine level was 11 μmol/L (range, 4-221 μmol/L) and 165 patients (37%) had hyperhomocysteinemia. The MELD (23 ± 10 vs. 20 ± 9 points, P < 0.001), and Child-Pugh (11 ± 2 vs. 9 ± 2 points, P < 0.001) scores were higher in patients with hyperhomocysteinemia. Episodes of thrombosis occurred in 91 patients (20%), but there was no significant difference in patients with or without hyperhomocysteinemia (19 vs. 21%, P = 0.6). Hyperhomocysteinemia was associated with reduced graft (105 ± 4 vs. 119 ± 2 months; P = 0.005), and patient survival (125 ± 33 vs. 131 ± 2 months; P = 0.006).

CONCLUSIONS

Hyperhomocysteinemia is frequently present in patients with cirrhosis and is associated with severe liver disease and reduced graft and patient survival after liver transplantation. The negative impact hyperhomocysteinemia has on graft and patient survival is not related to thrombosis.

Reducing the load: the evolution and management of obesity and nonalcoholic steatohepatitis before liver transplantation

1. Obesity is common in patients with end-stage liver disease of any cause. 2. Obesity is associated with comorbidities that can affect liver transplant candidacy, such as metabolic syndrome (diabetes, hyperlipidemia, and hypertension), cardiovascular disease, pulmonary disorders (related to obstructive sleep apnea), renal dysfunction, and malignancies. 3. Nonalcoholic steatohepatitis is the only indication for transplantation that is increasing in frequency, and it may soon become the leading indication. 4. There is no set body mass index above which liver transplantation is contraindicated. Transplant candidacy and outcomes depend on the cumulative comorbidities of the individual patient. 5. Weight loss is an important component of metabolic syndrome management and is recommended before liver transplantation. 6. Bariatric surgery may be considered in carefully selected patients with well-compensated cirrhosis but is not recommended in patients with decompensated cirrhosis.

Metabolic syndrome in liver transplantation: relation to etiology and immunosuppression

Excessive weight gain, hypertension, hyperlipidemia, and diabetes are frequently observed in patients having undergone liver transplantation (LTx). These alterations are probably multifactorial in origin, and cluster to generate a metabolic syndrome (MS), increasing the risk of cardiovascular events. We assessed the prevalence of MS (National Cholesterol Education Program-Adult Treatment Panel III criteria) in 296 LTx patients in the course of regular follow-up, at least 6 months after transplantation (median, 38 months). Several pre-LTx and post-LTx data were collected to identify the factors associated with the presence of MS. In a subset of 99 patients, insulin resistance was measured by the homeostasis model assessment. High blood pressure was present in 53% of cases, hyperlipidemia in 51%, high glucose in 37%, and enlarged waist circumference in 32%. Overall, MS (defined as 3 or more of the above features) was present in 44.5% of cases. Insulin resistance (homeostasis model assessment > 2.7) was observed in 41% of cases. Hypertension and hyperlipidemia were more frequent in subjects on cyclosporine than in tacrolimus-treated cases, whereas the type of immunosuppressive drug had no effect on the prevalence of diabetes, enlarged waist, and MS. In a logistic regression analysis, only pre-LTx body mass index (odds ratio, 1.20), body mass index increase (odds ratio, 1.18), and pre-LTx diabetes (odds ratio, 2.36) predicted MS; age, gender, etiology of liver disease, time from LTx, type of immunosuppressive drug, and previous hepatocellular carcinoma were removed from the model. Disorders related to MS are frequent in LTx patients, and are related to both pre-LTx conditions and to weight gain. Weight control is mandatory in LTx patients to prevent risk factors of premature atherosclerosis.