Vitamin D and osteocalcin levels in liver transplant recipients. Is osteocalcin a reliable marker of bone turnover in such cases?

Nutrition Support in Liver Transplantation and Postoperative Recovery: The Effects of Vitamin D Level and Vitamin D Supplementation in Liver Transplantation

Vitamin D plays an important role in the arena of liver transplantation. In addition to affecting skeletal health significantly, it also clinically exerts immune-modulatory properties. Vitamin D deficiency is one of the nutritional issues in the perioperative period of liver transplantation (LT). Although vitamin D deficiency is known to contribute to higher incidences of acute cellular rejection (ACR) and graft failure in other solid organ transplantation, such as kidneys and lungs, its role in LT is not well understood. The aim of this study was to investigate the clinical implication of vitamin D deficiency in LT. LT outcomes were reviewed in a retrospective cohort of 528 recipients during 2014-2019. In the pre-transplant period, 55% of patients were vitamin-D-deficient. The serum vitamin D level was correlated with the model for end-stage liver disease (MELD-Na) score. Vitamin D deficiency in the post-transplant period was associated with lower survival after LT, and the post-transplant supplementation of vitamin D was associated with a lower risk of ACR. The optimal vitamin D status and vitamin D supplementation in the post-transplant period may prolong survival and reduce ACR incidence.

Changes in vitamin D binding protein and vitamin D concentrations associated with liver transplantation

BACKGROUND

Vitamin D deficiency is associated with fractures, infections and death. Liver disease impairs vitamin D and vitamin D binding protein (DBP) metabolism.

AIMS

We aimed to determine the impact of liver transplantation on vitamin D, particularly on DBP and free vitamin D concentrations.

METHODS

Serum 25(OH)D, 1,25(OH)(2) D and DBP concentrations were measured in 202 adults before liver transplantation and 3 months later in 155. Free vitamin D concentrations were estimated from these values. Risk factors for 25(OH)D deficiency (<20 ng/ml) and low 1,25(OH)(2) D (<20 pg/ml) were examined with logistic regression, and changes in concentrations following transplantation with linear regression.

RESULTS

Pretransplant, 84% were 25(OH)D deficient, 13% had 25(OH)D concentrations <2.5 ng/ml, and 77% had low 1,25(OH)(2) D. Model for end-stage liver disease score ≥ 20 (P < 0.005) and hypoalbuminemia (P < 0.005) were associated with low 25(OH)D and 1,25(OH)(2) D concentrations. Following transplantation, 25(OH)D concentrations increased a median of 17.8 ng/ml (P < 0.001). Albumin increased from a median of 2.7 to 3.8 g/dl (P < 0.001) and DBP from 8.6 to 23.8 mg/dl (P < 0.001). Changes in total 25(OH)D were positively and independently associated with changes in DBP (P < 0.05) and albumin (P < 0.001). Free 25(OH)D concentrations rose from 6.0 to 9.7 pg/ml (P < 0.001). In contrast, total 1,25(OH)(2)D concentrations rose only by 4.3 pg/ml (P < 0.001) and free 1,25(OH)(2D concentrations declined (P < 0.001).

CONCLUSIONS

Serum total and free 25(OH)D and DBP concentrations rose substantially following transplantation, while 1,25(OH)(2) D concentrations showed modest changes and free 1,25(OH)(2) D decreased. Studies of the effects of vitamin D status on diverse transplant complications are needed.

Isoform of fibronectin mediates bone loss in patients with primary biliary cirrhosis by suppressing bone formation

Osteoporosis is a major cause of morbidity and decreased quality of life in patients with chronic cholestatic liver disease. It is established that this osteoporosis results from decreased bone formation, but the mechanisms for the interaction between liver and bone remain elusive. The aim of this study was to test the hypothesis that an increase in the production of cellular fibronectins during liver disease may result in decreased osteoblast-mediated mineralization and thus explain the decrease in bone formation. We performed a prospective cross-sectional study in patients with primary biliary cirrhosis and matched controls, followed by experiments on human and mouse osteoblasts in culture and injections in mice in vivo. In patients with primary biliary cirrhosis, the oncofetal domain of fibronectin correlated significantly with the decrease in osteocalcin, a marker of bone formation (r = -0.57, p < 0.05). In vitro, amniotic fluid fibronectin (aFN) containing mainly the oncofetal domain and EIIIA domain resulted in decreased osteoblast-mediated mineralization in human osteoblasts (69% decrease at 100 microg/ml; p < 0.01) and mouse osteoblasts (71% decrease; p < 0.05). Removing the EIIIA domain from aFN similarly suppressed mineralization by osteoblasts (78% decrease; p < 0.05). Injection of labeled aFN in mice showed that it infiltrates the bone, and its administration over 10 days resulted in decreased trabecular BMD (17% drop; p < 0.05), mineralizing surface (30% drop; p < 0.005), and number of osteoblasts (45% drop; p < 0.05). Increased production of a fibronectin isoform containing the oncofetal domain and its release in the circulation in patients with primary biliary cirrhosis is at least partially responsible for the decrease in bone formation seen in these patients. This establishes that a molecule that has thus far been viewed as an extracellular matrix protein exerts hormone-like actions.

Clinical benefits of biochemical markers of bone turnover in Egyptian children with chronic liver diseases

AIM: To investigate the association between serum insulin-like growth factor 1 (IGF-1), osteocalcin, and parathyroid hormone (PTH) levels with the etiology and clinical condition of patients with chronic liver disease.

METHODS: Eighty children with hepatocellular damage were divided into 3 groups according to the etiology of disease infection: bilharziasis (9 patients), hepatitis B virus (HBV, 12 patients) and hepatitis C virus (HCV, 29 patients). The Child score index was found as A in 24 patients, B in 22 patients, C in 4 patients. Thirty healthy children served as control group. HBsAg, HBcAbIgM, HBcAbIgG, and anti-HCV were detected using ELISA technique. HCV-RNA was measured by reverse transcription polymerase chain reaction (RT-PCR). Anti-bilharzial antibodies were detected by indirect haem- agglutination test. Liver function tests were performed using autoanalyser. Serum IGF-1, osteocalcin and PTH levels were measured by ELISA technique. Abdominal ultrasonography was also conducted.

RESULTS: Serum IGF-1 level was significantly lower in all patient groups with liver diseases, while serum osteocalcin and PTH levels were significantly elevated in patients with HBV and HCV infections compared with the control group. Serum osteocalcin and PTH concentrations were measured with the severity of liver disease from Child A to C. Child A patients unexpectedly showed significantly reduced IGF-1 levels in comparison to patients staged as Child B or C. Serum osteocalcin level was negatively correlated with albumin (14.7 ± 0.54 vs 3.6 ± 0.10, P < 0.05), while that for PTH was positively correlated with total protein (70.1 ± 2.17 vs 6.7 ± 0.10, P < 0.05) in patients with HCV infection.

CONCLUSION: Low serum IGF-1 level seems to play a critical role in the bone loss in patients with chronic liver disease. Elevated biochemical markers of bone remodeling suggest high-turnover in patients with viral infection and reflect severity of the clinical stage.

Liver transplantation for alcoholic liver disease: current concepts and length of sobriety

1. The 1-year and 5-year actuarial survival rates following liver transplantation for patients with alcoholic liver disease are 82% and 68%, respectively, in the United States and 85% and 70%, respectively, in Europe. These survival rates are similar to the outcomes of patients who undergo transplantation for other types of chronic liver disease. 2. Posttransplant improvements in health-related quality of life are similar in patients who undergo transplantation for alcoholic liver disease compared to those who undergo transplantation for other causes of end-stage liver disease. 3. Approximately 20% of patients who undergo transplantation for alcoholic liver disease use alcohol posttransplant, with one-third of these individuals exhibiting repetitive or heavy drinking. Surprisingly, little evidence exists to document a significant detrimental effect on graft or patient survival associated with resumption of drinking. 4. There are few reliable predictors of relapse in alcoholic patients after liver transplantation. Although not supported by all studies, abstinence of fewer than 6 months prior to transplantation may be a reasonable predictor of recidivism and is widely employed as a criterion for listing for liver transplantation. There are no good data to determine if some patients with sobriety fewer than 6 months might benefit from liver transplantation.

Orthotopic liver transplantation for alcoholic liver disease: a retrospective analysis of survival, recidivism, and risk factors predisposing to recidivism

The aim of this study performed at the Liver Unit at the Queen Elizabeth Hospital, Birmingham, UK, is to assess posttransplantation alcohol consumption and identify risk factors associated with recidivism. This retrospective case-control study used a self-report questionnaire to assess pretransplantation and posttransplantation drinking, and a retrospective cohort study used patient notes to analyze risk factors for recidivism. Of 64 patients who underwent transplantation for alcoholic liver disease (ALD) between May 1996 and November 1999, a total of 49 surviving patients (40 men, 9 women) were available for study. The comparison group consisted of 49 patients matched for age, sex, and date of transplantation who underwent transplantation for non-alcohol-induced chronic liver disease. Two-year patient survival rates were 82% in both study groups. The questionnaire response rate was 69.3% and 75.5% in patients with and without ALD, respectively. Data on recidivism (defined as any alcohol consumption after transplantation) were available in 46 of the 49 patients with ALD. Of these, 45.6% were drinking; 21.7% reported only occasionally drinking; 17.3%, moderate drinking; and 6.5%, heavy drinking. Information on alcohol consumption was available from 41 of the 49 controls. Of these, 52.5% consumed alcohol; 22.0% reported drinking only on special occasions; 24.4%, moderate drinking; and 4.9%, a return to heavy drinking. However, these differences were not statistically significant, and log-rank analysis found no significant difference in time to resumption of drinking. In the ALD cohort, no significant risk factors were identified to predict recidivism. No pretransplantation risk factors (including period of abstinence before transplantation) correlated with recidivism. Survival after transplantation for ALD is similar to that in other forms of chronic liver disease. Recidivism rates for patients with ALD are high, but patients with ALD do not drink more than their control counterparts posttransplantation. In most instances, alcohol consumption posttransplantation is minimal to moderate (<20 units/wk) and seems to be controlled.

Employment and alcohol use after liver transplantation for alcoholic and nonalcoholic liver disease: a systematic review

The purpose of the study is to evaluate patterns of employment and alcohol use among liver transplant recipients with alcoholic (ALD) and nonalcoholic liver disease (non-ALD). MEDLINE, EMBASE, and bibliographic searches identified 5,505 potentially relevant articles published between January 1966 and October 1998. Eighty-two studies reporting data on 5,020 transplant recipients met our inclusion criteria. Pre-orthotopic liver transplantation (OLT), 29% of transplant recipients with ALD and 59% of those with non-ALD worked versus 33% and 80% at 3 years for transplant recipients with ALD and non-ALD, respectively (P <.00001 for each interval). We found no difference in the proportion of transplant recipients with ALD and non-ALD reporting early alcohol use post-OLT: 4% versus 5% at 6 months and 17% versus 16% at 12 months. However, among post-OLT drinkers, transplant recipients with non-ALD were more likely to drink moderately and those with ALD to drink excessively. At 7 years post-OLT, 32% of the patients with ALD reported using alcohol. The odds ratio for alcohol use among patients who maintained abstinence for fewer than 6 months pre-OLT versus those who maintained abstinence for greater than 6 months was 7.8 (95% confidence interval, 4.0 to 15.3). Before OLT and at long-term follow-up, substantially more transplant recipients with non-ALD than ALD were employed. The proportions of transplant recipients with ALD and non-ALD reporting alcohol use did not differ, although those with ALD tended to consume greater quantities.

Bone loss after liver transplantation is not prevented by cyclical etidronate, calcium and alphacalcidol. The Liver Transplant Group, Groningen

After orthotopic liver transplantation (OLT) bone mass rapidly declines and vertebral fracture rate increases. We studied bone loss and parameters of bone turnover in 53 consecutive patients. In an attempt to reduce bone loss the patients were prophylactically treated with cyclical etidronate in addition to daily 1 alpha-hydroxyvitamin D3 and calcium. During the first 3 months after transplantation median lumbar spinal bone mineral density (BMD) decreased 4.5%; subsequently no significant changes occurred. Median hip BMD continued to fall during the first post-transplantation year and deteriorated 7% over the whole study period. New vertebral fractures were seen in 25% of the patients, which is not lower than previously reported rates in patients not receiving cyclical etidronate. Parathyroid hormone levels increased after OLT (p = 0.01), but remained within normal ranges. Urinary hydroxyproline levels were increased and normalized in the second half-year after OLT. Elevated fasting calciuria increased further after OLT. 1,25-Dihydroxy-vitamin D3 levels were lowered pre-OLT (25 vs 66 pmol/ 1, p < 0.001) and normalized at 3 months after OLT. Serum osteocalcin concentrations remained unchanged and were reduced compared with levels in healthy controls. In summary, increased bone resorption occurs after OLT with persistent decreased bone formation, leading to vertebral fracture in 25% of patients. Etidronate, 1 alpha-calcidol and calcium treatment did not prevent bone loss.