Evaluation of the effect of age on functioning hepatocyte mass and liver blood flow using liver scintigraphy in preoperative estimations for surgical patients: comparison with CT volumetry

Human umbilical cord mesenchymal stem cell-derived exosome ameliorate doxorubicin-induced senescence

BACKGROUND

Cellular senescence refers to a condition where cells permanently cease division while maintaining metabolic activity. Doxorubicin (Dox) is known as an agent of induction of cellular senescence. This study aimed to explore the potential role of human umbilical cord mesenchymal stem cell-derived exosomes (hucMSC-Exo) in mitigating Dox induced senescent.

METHOD

NIH3T3 cells were treated by various concentrations of Dox with or without hucMSC-Exo, cell morphology, viability, migration, senescence-associated SA-β-Gal staining were monitored. Cellular senescence was induced in C57BL/6J mice via administration of 5 mg/kg Doxorubicin, followed by treatment with hucMSC-Exo or metformin. Assessments included body weight, liver and kidney weight, colon length, SA-β-Gal staining of kidney and skin, molecular biomarkers of aging such as p16INK4A, p53, and p21Waf1/Clip1 to evaluate senescence status.

RESULT

We found that after the treatment of exosomes or metformin improved several aging-related phenotypes in both mouse and cellular models, including increases in body weight, liver and kidney weights, and the reduction of SA-β-Gal positive cells in kidney and skin tissues as well as cell models. At the molecular level, hucMSC-Exo resulted in the downregulation of inflammatory factors and senescence markers in liver and kidney tissues as well as cell models.

CONCLUSION

Our study demonstrates hucMSC-Exo may ameliorate Dox induced senescence either in NIH3T3 cells or in mice.

Age-dependent differences in FIB-4 predictions of fibrosis in patients with MASLD referred from primary care

BACKGROUND

Fibrosis 4 (FIB-4) is widely used to triage patients with metabolic dysfunction-associated steatotic liver disease. Given that age is part of FIB-4, higher scores may be expected in the elderly population. This led to the proposal of using a higher threshold of FIB-4 to triage patients aged ≥65. Our main objective is to evaluate how age modifies the association between the FIB-4 index and disease severity based on the vibration-controlled transient elastography (VCTE) "rule of 5s."

METHODS

In this cross-sectional study, we prospectively analyzed data from a primary care referral pathway. We used liver stiffness measurement by VCTE as a reference standard for liver risk. We modeled with ordinal regression the exceedance probabilities of finding different liver stiffness measurement thresholds according to FIB-4, and how age modifies FIB-4 predictions.

RESULTS

Nine hundred eighty-five participants with complete data were used for modeling. Participants aged ≥65 had a higher prevalence of advanced liver disease estimated by VCTE and higher FIB-4 values than those <65 (85.9% vs. 20.2% for FIB-4 ≥1.3, and 46.5% vs. 6.5% for FIB-4 ≥2.0). In participants age ≥65, the negative predictive value for VCTE ≥10 kPa of FIB-4 <1.3 was 100% versus FIB-4 <2.0 was 83%. Age significantly modified FIB-4-based prediction of fibrosis, but predictions at a threshold of 1.3 or 2 were only minimally altered. For higher FIB-4 threshold (ie, 2.7), age strongly modified FIB-4 predictions of liver stiffness measurement.

CONCLUSIONS

Age does not relevantly modify FIB-4 predictions when using the common threshold of 1.3. Our data suggest no rationale for increasing the FIB-4 threshold to 2 for undergoing further testing in patients aged ≥65. However, the meaning of a FIB-4 of 2.7 strongly changes with age. This cutoff for ages over 65 is not enough to define high-risk and would not warrant direct referral.

Impact of aging on hepatic reserve after preoperative portal vein embolization in hepatectomy for perihilar cholangiocarcinoma

PURPOSE

In the current situation of an increasing older adult population with perihilar cholangiocarcinoma (PHCC), the benefits and risks of surgical treatment of PHCC in older people remain controversial. Portal vein embolization (PVE) is a useful preoperative procedure to improve hepatic reserve in the future remnant liver (FRL) and avoid postoperative liver failure after extended hepatectomy for PHCC. This study aimed to evaluate the influence of aging on PVE.

METHODS

We enrolled 25 patients who underwent right hepatectomy with percutaneous transhepatic PVE. Participants aged <70 years (n = 13) and ≥70 years (n = 12) were compared; correlation coefficients were evaluated using all cases. The FRL volume/total liver volume (FRLV/TLV) ratio and the indocyanine green (ICG) clearance rate (ICG-K) fraction of FRL to total liver (ICG-Krem) were analyzed as FRL hepatic reserves.

RESULTS

FRLV/TLV ratio increased after PVE in <70 years and ≥70 years groups (p = 0.002 and p = 0.013, respectively). The change in ICG-K values from before to after PVE varied between both groups (p = 0.040). The ICG-Krem value after PVE increased only in the <70 years group (p = 0.009). A review of all cases showed a negative correlation between the change (after - before PVE) in the ICG-K and ICG-Krem values and age (r = -0.4827, p = 0.0145 and r = -0.4328, p = 0.0306, respectively).

CONCLUSIONS

This study showed aging suppresses hepatic reserve improvement in the FRL, particularly in ICG clearance after PVE in PHCC cases.

Comparative effects of lifelong moderate-intensity continuous training and high-intensity interval training on blood lipid levels and mental well-being in naturally ageing mice

OBJECTIVE

This study aimed to investigate the impact of lifelong exercise, including both moderate-intensity continuous training and high-intensity interval training, on blood lipid levels and mental behaviour in naturally ageing mice to identify effective exercise strategies for ageing-related health issues.

METHODS

Six-week-old male BALB/c mice were randomly assigned to one of four groups: young control (YC), natural ageing control (OC), lifelong moderate-intensity continuous exercise (EM), and lifelong high-intensity interval exercise (EH) groups. The EM group was trained at a speed corresponding to 70 % of the maximum running speed, while the EH group was trained at a running speed alternating between 50 % of the maximum running speed, 70 % of the maximum running speed, and 90 % of the maximum running speed. All exercise sessions were conducted three times per week, with each session lasting 50 min. Behavioural tests and blood sample collection were conducted at 72 weeks of age.

RESULTS

Ageing in mice led to changes in muscle and fat mass. Both the EM and EH groups showed greater muscle mass and lower fat mass than did the OC group. Ageing was associated with elevated anxiety (fewer open arm entries, time spent in the central region) and depression (lower sucrose preference) indicators. However, these changes were reversed in both exercise groups, with no differences between the two exercise groups. Blood lipid levels, including total cholesterol (TC), total triglycerides (TGs), low-density lipoprotein (LDL), and free fatty acid (FFA) levels, were greater in the OC group than in the YC group. Additionally, the OC group exhibited lower high-density lipoprotein (HDL) levels. However, both the EM and EH groups exhibited improved lipid profiles compared to those of the YC group.

CONCLUSION

Lifelong exercise, whether moderate-intensity continuous or high-intensity interval training, can preserve body health during ageing, prevent anxiety and depression, and maintain stable blood lipid levels. Both exercise types are equally effective, suggesting that exercise intensity may not be the critical factor underlying these beneficial adaptations.

Liver regeneration of living donor after liver donation for transplantation: Disparity in the left and right remnant liver

Donor safety is crucial for living donor liver transplantation (LDLT), and sufficient liver regeneration significantly affects outcomes of living donors. This study aimed to investigate clinical factors associated with liver regeneration in living donors. The study retrospectively reviewed 380 living donors who underwent liver donation at Chang Gung Memorial Hospital in Linkou. The clinical characteristics and medical parameters of donors were analyzed and compared according to liver donation graft type. There were 355 donors (93.4%) with right hemi-liver donations and 25 donors (6.6%) with left hemi-liver donations. Left hemi-liver donors had a higher body mass index (BMI) and a larger ratio of remnant liver volume (RLV) to total liver volume (TLV). However, the 2 groups showed no significant difference in the liver regeneration ratio. The type of remnant liver (P < .001), RLV/body weight (P = .027), RLV/TLV (P < .001), serum albumin on postoperative day 7 and total bilirubin levels on postoperative day 30 were the most significant factors affecting liver regeneration in living donors. In conclusion, adequate liver regeneration is essential for donor outcome after liver donation. The remnant liver could eventually regenerate to an adequate volume similar to the initial TLV before liver donation. However, the remnant left hemi-liver had a faster growth rate than the remnant right hemi-liver in donors.

Aging Biomarker Consortium, Jiang M, Zheng Z, Wang X, Chen Y, Qu J, Ding Q, Zhang W, Liu YS, Yang J, Tang W, Hou Y, He J, Wang L, Huang P, Li LC, He Z, Gao Q, Lu Q, Wei L, Wang YJ, Ju Z, Fan JG, Ruan XZ, Guan Y, Liu GH, Pei G, Li J, Wang Y. A biomarker framework for liver aging: the Aging Biomarker Consortium consensus statement

In human aging, liver aging per se not only increases susceptibility to liver diseases but also increases vulnerability of other organs given its central role in regulating metabolism. Total liver function tends to be well maintained in the healthy elderly, so liver aging is generally difficult to identify early. In response to this critical challenge, the Aging Biomarker Consortium of China has formulated an expert consensus on biomarkers of liver aging by synthesizing the latest scientific literature, comprising insights from both scientists and clinicians. This consensus provides a comprehensive assessment of biomarkers associated with liver aging and presents a systematic framework to characterize these into three dimensions: functional, imaging, and humoral. For the functional domain, we highlight biomarkers associated with cholesterol metabolism and liver-related coagulation function. For the imaging domain, we note that hepatic steatosis and liver blood flow can serve as measurable biomarkers for liver aging. Finally, in the humoral domain, we pinpoint hepatokines and enzymatic alterations worthy of attention. The aim of this expert consensus is to establish a foundation for assessing the extent of liver aging and identify early signs of liver aging-related diseases, thereby improving liver health and the healthy life expectancy of the elderly population.

Donor Evaluation Protocol for Live and Deceased Donors

Donor evaluation is a critical step before proceeding with liver transplantation (LT) in both deceased donor LT (DDLT) and living donor LT (LDLT). A good, healthy graft is necessary for the success of the transplantation. Other issues in selecting a donor include the transmission of infections and malignancies from the donor. Because of the scarcity of cadaver organs, an increasing number of extended-criteria donors, or 'marginal donors', are being utilized. LDLT also has potential risks to the donor, and donor safety needs to be kept in mind before proceeding with LT. The current review highlights the factors to be considered during donor evaluation for living and deceased donors before LT.

Impacts of gut microbiota alteration on age-related chronic liver diseases

The gut microbiome and its metabolites are involved in developing and progressing liver disease. Various liver illnesses, such as non-alcoholic fatty liver disease, alcoholic liver disease, hepatitis C, and hepatocellular carcinoma, are made worse and have worse prognoses with aging. Dysbiosis, which occurs when the symbiosis between the microbiota and the host is disrupted, can significantly negatively impact health. Liver disease is linked to qualitative changes, such as an increase in hazardous bacteria and a decrease in good bacteria, as well as quantitative changes in the overall amount of bacteria (overgrowth). Intestinal gut microbiota and their metabolites may lead to chronic liver disease development through various mechanisms, such as increasing gut permeability, persistent systemic inflammation, production of SCFA, bile acids, and alteration in metabolism. Age-related gut dysbiosis can disrupt the communication between gut microbiota and the host, impacting the host's health and lifespan. With aging, a gradual loss of the ability to maintain homeostasis because of structural alteration and gut dysbiosis leads to the disease progression in end-stage liver disease. Recently chronic liver disease has been identified as a global problem. A large number of patients are receiving liver transplants yearly. Thereby gut microbiome ecology is changing in the patients of the gut due to the changes in pathophysiology during the preoperative stage. The present review summarises the age-associated dysbiosis of gut microbial composition and its contribution to chronic liver disease. This review also provides information about the impact of liver transplant on the gut microbiome and possible disadvantageous effects of alteration in gut microbiota.

Hemodynamic changes in the portal vein with age: evaluation using four-dimensional flow MRI

Aging process is associated with gradual change of liver function and structure. The goal of this study was to evaluate age-related hemodynamic changes in the portal vein (PV) using four-dimensional (4D) flow MRI in healthy adults. A total of 120 healthy subjects were enrolled and categorized into groups A (n = 25, 30-39 years), B (n = 31, 40-49 years), C (n = 34, 50-59 years), and D (n = 30, 60-69 years). All subjects underwent 4D flow data acquisition using a 3-T MRI system to measure the hemodynamic parameters in the main PV. The clinical characteristics and 4D flow parameters were compared among the groups using analysis of variance and analysis of covariance after controlling for significant covariates, accordingly. The outcome metric applying the age-related quadratic model to estimate the age at which 4D flow parameters are the highest (the peak age) as well as the rates of age-related 4D flow changes was estimated. The average area, average through-plane velocity, peak velocity magnitude, average net flow, peak flow, and net forward volume in group D were significantly lower than those in groups A, B and C (P < 0.05). Group C showed significantly lower values of the average through-plane velocity and peak velocity magnitude than those of group B (P < 0.05). The peak age computed was approximately 43-44 years of age for all 4D flow parameters. The rates of age-related 4D flow changes for all 4D flow parameters were negatively correlated with age (P < 0.05). The volume and velocity of the blood flow through the PV peaked at approximately 43-44 years of age and decreased significantly after 60 years of age.

Biomarkers of aging

Aging biomarkers are a combination of biological parameters to (i) assess age-related changes, (ii) track the physiological aging process, and (iii) predict the transition into a pathological status. Although a broad spectrum of aging biomarkers has been developed, their potential uses and limitations remain poorly characterized. An immediate goal of biomarkers is to help us answer the following three fundamental questions in aging research: How old are we? Why do we get old? And how can we age slower? This review aims to address this need. Here, we summarize our current knowledge of biomarkers developed for cellular, organ, and organismal levels of aging, comprising six pillars: physiological characteristics, medical imaging, histological features, cellular alterations, molecular changes, and secretory factors. To fulfill all these requisites, we propose that aging biomarkers should qualify for being specific, systemic, and clinically relevant.

Nodular Regenerative Hyperplasia Is Not a Rare Condition After Liver Transplantation: Incidence, Predictive Factors, and Impact on Survival

BACKGROUND

The objectives of this study were to evaluate incidence and to identify the risk factors of occurrence and the predictive factors of symptomatic forms of nodular regenerative hyperplasia (NRH) after liver transplantation (LT).

METHODS

To identify risk factors of NRH following LT, we included 1648 patients transplanted from 2004 to 2018 and compared the patients developing NRH after LT to those who did not. To identify predictive factors of symptomatic NRH, we selected 115 biopsies displaying NRH and compared symptomatic to asymptomatic forms. Symptomatic NRH was defined as the presence of ascites, esophageal varices, hepatic encephalopathy, portal thrombosis, retransplantation, or death related to NRH.

RESULTS

The incidence of NRH following LT was 5.1%. In multivariate analysis, the independent factor of developing NRH after LT was the donor's age (odds ratio [OR] = 1.02; confidence interval, 1.01-1.03; P = 0.02). Symptomatic forms occurred in 29 (25.2%) patients: 19 (16.5%) patients presented with ascites, 13 (11.3%) with esophageal varices, 4 (3.5%) with hepatic encephalopathy, and 8 (7%) with portal thrombosis. The median period before the onset of symptoms was 8.4 (1.5-11.3) y after LT. The spleen size at diagnosis/before LT ratio (OR = 12.5; 114.17-1.37; P = 0.0252) and thrombectomy during transplantation (OR = 11.17; 1.48-84.11; P = 0.0192) were associated with symptomatic NRH in multivariate analysis.

CONCLUSIONS

NRH following LT is frequent (5.1%) and leads to symptomatic portal hypertension in 25.2% of patients. Using older grafts increases the risk of developing NRH after LT. Clinicians should screen for signs of portal hypertension, particularly in measuring spleen size.

Gender-specific liver aging and magnetic resonance imaging

The number of imaging studies performed on elderly individuals will increase in the next several decades. It is important to understand normal age-related changes in the structural and functional imaging appearance of the liver. This article highlights a number of liver aging aspects which are particularly relevant to magnetic resonance imaging (MRI). Physiology of aging liver is associated with a reduction in size, in perfusion, and in function. Pulsed echo-Doppler showed substantial reduction of portal flow in elderly subjects, particularly those after the age of 75 years old. An MRI biomarker diffusion derived vessel density (DDVD) demonstrated that liver microperfusion volume in healthy females starts to decrease even before menopause age. Liver fat content and iron content increase with aging, and the change is more substantial in women after menopause. Adult men have higher liver fat and iron contents than women from the start and change less during aging. Nonalcoholic fatty liver disease (NAFLD) is very common among assumed healthy subjects. There is a male predominance of NAFLD from the paediatric population up to fifth decade of life in adults. After the age of 60 years, women overtake their male counterparts in prevalence of NAFLD. Higher liver fat leads to decreased apparent diffusion coefficient (ADC) and intravoxel incoherent motion (IVIM)-D_slow measures. Higher liver iron content shortens T2* measure, lower ADC and IVIM-D_slow measures, increases imaging noises and decreases liver visibility. Young women have high liver T1rho value and then decrease substantially, while liver T1rho in men remains relatively unchanged with aging. In positron emission tomography (PET) studies, aging is associated with an increase of both liver fluorine-18-fluorodeoxyglucose maximum standard uptake and mean standard uptake values.

PET/CT Variants and Pitfalls in Liver, Biliary Tract, Gallbladder and Pancreas

A wide variety of pathological anomalies may occur in the liver, biliary system, and pancreas. It is a necessity to use many different imaging techniques in order to distinguish such varied pathologies, especially those from malignant processes. Positron Emission Tomography/Computed Tomography (PET/CT) is an imaging method that has proven its diagnostic value in oncology and can be used for different clinical purposes. Fluoro-18 fluoro-2-deoxy-D-glucose has a wide range of uses as a dominant radiopharmaceutical in routine molecular imaging, however, molecular imaging has started to play a more important role in personalized cancer treatment in recent years with new Fluoro-18 and Gallium-68 labeled tracers. Although molecular imaging has a strong diagnostic effect, the surprises and pitfalls of molecular imaging can lead us to unexpected and misleading results. Prior to PET/CT analysis and reporting, information about possible technical and physiological pitfalls, normal histological features of tissues, inflammatory pathologies, specific clinical features of the case, treatment-related complications and past treatments should be evaluated in advance to avoid misinterpretation. In this review, the physiological and pathophysiological variants as well as pitfalls encountered in PET/CT imaging of the liver, biliary tract, gallbladder, and pancreas will be examined. Other benign and malignant pathologies that have been reported to date and that have led to incorrect evaluation will be listed. It is expected that the devices, software, and artificial intelligence applications that will be developed in the near future will enable much more effective and faster imaging that will reduce the potential causes of error. However, as a result of the dynamic and evolving structure of the information obtained by molecular imaging, the inclusion of the newly developed radiopharmaceuticals in routine practice will continue to carry new potentials as well as new troubles. Although molecular imaging will be the flagship of diagnostic oncology in the 21st century, the correct analysis and interpretation by the physician will continue to form the basis of achieving optimal performance.

Oxytocin promotes hepatic regeneration in elderly mice

Liver aging impairs the ability of hepatocyte regeneration. Recent studies have found that oxytocin (OT) plays an important role in promoting tissue repair and maintaining differentiation and regeneration of stem cells. Here, we reported that OT receptors, which are specifically located in hepatocytes, decrease with aging in human and mice. Interestingly, the level of serum OT also decline with age. Notably, OT promotes hepatocyte regeneration only in aged mice but not in young mice in vitro and in vivo. Further studies reveal that OT promotes autophagy in either AML12 mouse hepatocytes or aged mice after partial hepatectomy or with CCl4-induced acute liver injury. In conclusion, OT promotes liver regeneration, especially in aged mice, which may be achieved by promoting autophagy. All these results support the possibility of OT and its analog being a potent anti-aging drug and promote liver rejuvenation.

Age-related changes of standardized uptake values in the blood pool and liver: a decade-long retrospective study of the outcomes of 2,526 subjects

Background

Background activity on fluorine-18-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) is often used as a reference to assess a patient's response to tumor treatment. To produce a suitable background activity reference, we examined the variations in standardized uptake values (SUVs) in the blood pool and liver of a large multi-aged population.

Methods

A total of 2,526 subjects underwent ¹⁸F-FDG PET/CT examinations and were divided into 12 age groups. Pearson's partial correlation and multivariate regression analyses were performed to assess the associations between individual factors and SUVs of the blood pool and liver and to identify the factor that most influenced the SUVs. The mean SUVs across the age groups were also determined.

Results

Positive correlations were found between individual factors and SUVs. Age appeared to be the most important predictor of SUVs and was significantly associated with the blood pool SUV_max (ß=0.466, P=0.000), blood pool SUV_mean (ß=0.393, P=0.000), liver SUV_max (ß=0.347, P=0.000), and liver SUV_mean (ß=0.354, P=0.000). Blood pool and liver SUVs rose rapidly until the age of 20 and then showed a slow upward trend without reaching a plateau.

Conclusions

Age is an important factor that influences variations in the blood pool and liver SUVs. Our study clarified this understanding of age-related variations in SUVs and provided a normal range of blood pool and liver SUVs that may aid clinicians in evaluating tumors with greater accuracy.

Aging and Chronic Liver Disease

Aging increases the incidence of chronic liver disease (CLD), worsens its prognosis, and represents the predominant risk factor for its development at all different stages. The hepatic sinusoid, which is fundamental for maintaining liver homeostasis, is composed by hepatocytes, liver sinusoidal endothelial cells, hepatic stellate cells, and hepatic macrophages. During CLD progression, hepatic cells suffer deregulations in their phenotype, which ultimately lead to disease development. The effects of aging on the hepatic sinusoid phenotype and function are not well understood, nevertheless, studies performed in experimental models of liver diseases and aging demonstrate alterations in all hepatic sinusoidal cells. This review provides an updated description of age-related changes in the hepatic sinusoid and discusses the implications for CLD development and treatment. Lastly, we propose aging as a novel therapeutic target to treat liver diseases and summarize the most promising therapies to prevent or improve CLD and extend healthspan.

Transjugular intrahepatic portosystemic shunt in cirrhosis: An exhaustive critical update

More than five decades after it was originally conceptualized as rescue therapy for patients with intractable variceal bleeding, the transjugular intrahepatic portosystemic shunt (TIPS) procedure continues to remain a focus of intense clinical and biomedical research. By the impressive reduction in portal pressure achieved by this intervention, coupled with its minimally invasive nature, TIPS has gained increasing acceptance in the treatment of complications of portal hypertension. The early years of TIPS were plagued by poor long-term patency of the stents and increased incidence of hepatic encephalopathy. Moreover, the diversion of portal flow after placement of TIPS often resulted in derangement of hepatic functions, which was occasionally severe. While the incidence of shunt dysfunction has markedly reduced with the advent of covered stents, hepatic encephalopathy and instances of early liver failure continue to remain a significant issue after TIPS. It has emerged over the years that careful selection of patients and diligent post-procedural care is of paramount importance to optimize the outcome after TIPS. The past twenty years have seen multiple studies redefining the role of TIPS in the management of variceal bleeding and refractory ascites while exploring its application in other complications of cirrhosis like hepatic hydrothorax, portal hypertensive gastropathy, ectopic varices, hepatorenal and hepatopulmonary syndromes, non-tumoral portal vein thrombosis and chylous ascites. It has also been utilized to good effect before extrahepatic abdominal surgery to reduce perioperative morbidity and mortality. The current article aims to review the updated literature on the status of TIPS in the management of patients with liver cirrhosis.

A novel variant of the 13C-methacetin liver function breath test that eliminates the confounding effect of individual differences in systemic CO2 kinetics

The principle of dynamic liver function breath tests is founded on the administration of a ¹³C-labeled drug and subsequent monitoring of ¹³CO₂ in the breath, quantified as time series delta over natural baseline ¹³CO₂ (DOB) liberated from the drug during hepatic CYP-dependent detoxification. One confounding factor limiting the diagnostic value of such tests is that only a fraction of the liberated ¹³CO₂ is immediately exhaled, while another fraction is taken up by body compartments from which it returns with delay to the plasma. The aims of this study were to establish a novel variant of the methacetin-based breath test LiMAx that allows to estimate and to eliminate the confounding effect of systemic ¹³CO₂ distribution on the DOB curve and thus enables a more reliable assessment of the hepatic detoxification capacity compared with the conventional LiMAx test. We designed a new test variant (named "2DOB") consisting of two consecutive phases. Phase 1 is initiated by the intravenous administration of ¹³C-bicarbonate. Phase 2 starts about 30 min later with the intravenous administration of the ¹³C-labelled test drug. Using compartment modelling, the resulting 2-phasic DOB curve yields the rate constants for the irreversible elimination and the reversible exchange of plasma ¹³CO₂ with body compartments (phase 1) and for the detoxification and exchange of the drug with body compartments (phase 2). We carried out the 2DOB test with the test drug ¹³C-methacetin in 16 subjects with chronic liver pathologies and 22 normal subjects, who also underwent the conventional LiMAx test. Individual differences in the systemic CO₂ kinetics can lead to deviations up to a factor of 2 in the maximum of DOB curves (coefficient of variation CV ≈ 0.2) which, in particular, may hamper the discrimination between subjects with normal or mildly impaired detoxification capacities. The novel test revealed that a significant portion of the drug is not immediately metabolized, but transiently taken up into a storage compartment. Intriguingly, not only the hepatic detoxification rate but also the storage capacity of the drug, turned out to be indicative for a normal liver function. We thus used both parameters to define a scoring function which yielded an excellent disease classification (AUC = 0.95) and a high correlation with the MELD score (R_Spearman = 0.92). The novel test variant 2DOB promises a significant improvement in the assessment of impaired hepatic detoxification capacity. The suitability of the test for the reliable characterization of the natural history of chronic liver diseases (fatty liver-fibrosis-cirrhosis) has to be assessed in further studies.

Cirrhotic patients and older people

The global population is aging, and so the number of older cirrhotic patients is increasing. Older patients are characterised by a risk of frailty and comorbidities, and age is a risk factor for mortality in cirrhotic patients. The incidence of non-alcoholic fatty liver disease as an aetiology of cirrhosis is increasing, while that of chronic viral hepatitis is decreasing. Also, cirrhosis is frequently idiopathic. The management of portal hypertension in older cirrhotic patients is similar to that in younger patients, despite the greater risk of treatment-related adverse events of the former. The prevalence of hepatocellular carcinoma increases with age, but its treatment is unaffected. Liver transplantation is generally recommended for patients < 70 years of age. Despite the increasing prevalence of cirrhosis in older people, little data are available and few recommendations have been proposed. This review suggests that comorbidities have a considerable impact on older cirrhotic patients.

Age Matching of Elderly Liver Grafts With Elderly Recipients Does Not Have a Synergistic Effect on Long-term Outcomes When Both Are Carefully Selected

BACKGROUND

Older donors and recipients are increasingly considered for liver transplantation. Both donor and recipient age have a negative impact on outcomes. Large registry analyses show that older donors are frequently matched to older recipients. Whether age-related risks accumulate in a synergic negative effect on outcomes because of donor-recipient age matching is poorly understood.

METHODS

We investigated the impact of donor-recipient age interaction on patient and death-censored graft survival in multivariate Cox regressions in 849 transplants (January 2000 to December 2015).

RESULTS

Donors 70 years or older did not affect long-term patient or graft survival. Recipient age independently increased the risk of death (hazard ratio [HR], 1.03; 95% confidence interval [CI], 1.02-1.05, P < 0.0001), but donor-recipient age interaction was noninfluential. The negative impact of recipient age on patient survival was significant as early as 6 months after transplantation (HR, 1.06; 95% CI, 1.03-1.09; P = 0.00008). The adjusted risk of death was significant for patients aged 60 to 69 years (HR, 1.995; 95% CI, 1.40-2.85; P < 0.0001) and 70 years or older (HR, 2.001; 95% CI, 1.10-2.66; P = 0.04). In contrast, the risk of graft loss was not influenced by recipient age (HR, 1.02; 95% CI, 0.996-1.04; P = 0.11) or age interaction.

CONCLUSIONS

Older livers can be safely used in older recipients without jeopardizing graft and patient survival if other risk factors are minimized.

Macrophages in the Aging Liver and Age-Related Liver Disease

The number of individuals aged 65 or older is projected to increase globally from 524 million in 2010 to nearly 1. 5 billion in 2050. Aged individuals are particularly at risk for developing chronic illness, while being less able to regenerate healthy tissue and tolerate whole organ transplantation procedures. In the liver, these age-related diseases include non-alcoholic fatty liver disease, alcoholic liver disease, hepatitis, fibrosis, and cirrhosis. Hepatic macrophages, a population comprised of both Kupffer cells and infiltrating monocyte derived macrophages, are implicated in several chronic liver diseases and also play important roles in the homeostatic functions of the liver. The effects of aging on hepatic macrophage population dynamics, polarization, and function are not well understood. Studies performed on macrophages derived from other aged sources, such as the bone marrow, peritoneal cavity, lungs, and brain, demonstrate general reductions in autophagy and phagocytosis, dysfunction in cytokine signaling, and altered morphology and distribution, likely mediated by epigenetic changes and mitochondrial defects, that may be applicable to hepatic macrophages. This review highlights recent findings in macrophage developmental biology and function, particularly in the liver, and discusses the role of macrophages in various age-related liver diseases. A better understanding of the biology of aging that influences hepatic macrophages and thus the progression of chronic liver disease will be crucial in order to develop new interventions and treatments for liver disease in aging populations.

Challenges and innovations of drug delivery in older age

Both drug delivery performance and various age-related physical, mental and physiological changes can affect drug effectiveness and safety in elderly patients. The many drug delivery systems developed over the years include recent novel transdermal, nasal, pulmonary and orally disintegrating tablets that provide consistent, precise, timely and more targeted drug delivery. Certain drug delivery systems may be associated with suboptimal outcomes in the elderly because of the nature of drug present, a lack of appreciation of the impact of age-related changes in drug absorption, distribution and clearance, the limited availability of pharmacokinetic, safety and clinical data. Polypharmacy, patient morbidity and poor adherence can also contribute to sub-optimal drug delivery systems outcomes in the elderly. The development of drug delivery systems for the elderly is a poorly realised opportunity, with each system having specific advantages and limitations. A key challenge is to provide the innovation that best meets the specific physiological, psychological and multiple drug requirements of individual elderly patients.

The ageing pancreas: a systematic review of the evidence and analysis of the consequences

Senior people constitute the fastest growing segment of the population. The elderly are at risk for malnutrition, thought to be caused by reduced food intake or involution of the physiological capacity of the GI tract. Age-related changes are well known in other secretory organs such as liver, kidney and intestine. The pancreas, representing a metabolically active organ with uptake and breakdown of essential nutritional components, changes its morphology and function with age. During childhood, the volume of the pancreas increases, reaching a plateau between 20 and 60 years, and declines thereafter. This decline involves the pancreatic parenchyma and is associated with decreased perfusion, fibrosis and atrophy. As a consequence of these changes, pancreatic exocrine function is impaired in healthy older individuals without any gastrointestinal disease. Five per cent of people older than 70 years and ten per cent older than 80 years have pancreatic exocrine insufficiency (PEI) with a faecal elastase-1 below 200 μg g-1 stool, and 5% have severe PEI with faecal elastase-1 below 100 μg g-1 stool. This may lead to maldigestion and malnutrition. Patients may have few symptoms, for example steatorrhoea, diarrhoea, abdominal pain and weight loss. Malnutrition consists of deficits of fat-soluble vitamins and is affecting both patients with PEI and the elderly. Secondary consequences may include decreased bone mineral density and results from impaired absorption of fat-soluble vitamin D due to impaired pancreatic exocrine function. The unanswered question is whether this age-related decrease in pancreatic function warrants therapy. Therapeutic intervention, which may consist of supplementation of pancreatic enzymes and/or vitamins in aged individuals with proven exocrine pancreas insufficiency, could contribute to healthy ageing.

The effects of aging on hepatic microsomal scaling factor and hepatocellularity number in the horse

1. Scaling factor values for the in vitro-in vivo extrapolation of hepatic metabolic clearance for xenobiotics have not yet been determined in horses. Scaling factors were determined by comparing the total protein and or cytochrome (CYP) P450 content in microsomes and cryopreserved hepatocytes against the content in the liver. 2. Microsomal protein per gram of liver (MPPGL) and hepatocellularity number per gram of liver (HPGL) using CYP P450 content method ranged 41-73 mg/gram of liver (mean= 57 mg/gram of liver, n = 39) and 146-320 × 10⁶ cells/g of liver (mean = 227× 10⁶ cells/g of liver, n = 18), respectively and 156-352 × 10⁶ cells/g of liver (mean = 232× 10⁶ cells/g of liver) using total protein method. 3. A non-monotonic and inverse relationship between age and MPPGL and HPGL, respectively, was observed. Between one and 20 y of age, the liver cell size decreases as age increases. Subsequently, the cell size increases until the hepatocytes of the oldest horses approached the size found in the youngest horses. Hepatocyte density was inversely related to the size of the hepatocytes. 4. This study provides the first extensive and comprehensive data demonstrating the relationship between the size of hepatocytes and HPGL in any species.

Aging of the Liver: What This Means for Patients with HIV

As the HIV population continues to live longer as a result of antiretroviral therapy, liver-related mortality has become one of the leading causes of non-AIDS related death in this patient population. The liver possesses a remarkable regenerative capacity but undergoes complex biological changes in response to aging and inflammation that result in decreased cellular regeneration and a tipping of the scales towards fibrogenesis. Patients with HIV infection have serological evidence of ongoing inflammation, with elevations in some biomarkers persisting despite adequate virologic control. In addition, HIV-co-infected patients have markers of advanced age on liver biopsy and increased prevalence of fibrosis as compared to an age-matched HCV mono-infected cohort. In this review, we will discuss the biology of aging, age-related changes in the liver, and the relevant mechanisms by which HIV causes inflammation in the context of accelerated aging, fibrosis of the liver, and other viral co-infection.

Extended Criteria Donors in Liver Transplantation

Mortality rates on the liver transplant waiting list are increasing. The shortage of organs has resulted in higher utilization of extended criteria donors (ECDs), with centers pushing the limits of what is acceptable for transplantation. Donor quality is more appropriately represented as a continuum of risk, and careful selection and matching of ECD grafts with recipients may lead to excellent outcomes. Although there is no precise definition for what constitutes an ECD liver, this review focuses on frequently cited characteristics, including donor age, steatosis, donation after cardiac death, and donors with increased risk of disease transmission.

Relation of Alanine Aminotransferase Levels to Cardiovascular Events and Statin Efficacy

The relation between hepatic serum markers within the normal range and cardiovascular risk is uncertain. We sought to address this issue within a prospective randomized trial of statin therapy. Men and women (n = 17,515) free of cardiovascular disease participating in a randomized placebo controlled trial of rosuvastatin 20 mg/day had baseline levels of alanine aminotransferase (ALT) below <40 IU/l and were followed prospectively for the first-ever cardiovascular events. Cox proportional hazards models were used to calculate the relative risks of these events according to increasing tertiles and each SD increase in baseline ALT levels. ALT levels at study entry, all within the normal range, were inversely associated with age, smoking status, and inflammation and were positively associated with male gender, alcohol use, and triglycerides. Incident cardiovascular event rates were highest in those in the lowest tertile of baseline ALT; specifically, incidence rates were 1.43, 0.98, and 0.85 per 100 person-years of exposure for those in the lowest, middle, and highest tertile of baseline ALT within the normal range, respectively (p <0.001). These inverse effects remained statistically significant after multivariate adjustment for a wide range of vascular risk factors risk markers such that each higher SD unit of ALT was associated with an 18% lower event rate (relative risk 0.82, 95% confidence interval 0.72 to 0.93, p = 0.002). The efficacy of statin therapy was not modified by baseline ALT level. In conclusion, increasing ALT levels within the normal range are inversely associated with future cardiovascular risk but had limited clinical utility and also did not modify the efficacy of statin therapy.

Opposite associations between alanine aminotransferase and γ-glutamyl transferase levels and all-cause mortality in type 2 diabetes: Analysis of the Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) study

AIMS

Reported associations between liver enzymes and mortality may not hold true in type 2 diabetes, owing to a high prevalence of non-alcoholic fatty liver disease, which has been linked to cardiovascular disease and mortality in its own right. Our study aimed to determine whether alanine aminotransferase (ALT) or γ-glutamyl transferase (GGT) levels predict mortality in type 2 diabetes, and to examine possible mechanisms.

METHODS

Data from the Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) study were analyzed to examine the relationship between liver enzymes and all-cause and cause-specific mortality over 5years.

RESULTS

Over 5years, 679 (6.9%) individuals died. After adjustment, for every standard deviation increase in ALT (13.2U/L), the HR for death on study was 0.85 (95% CI 0.78-0.93), p<0.001. Conversely, GGT >70U/L, compared with GGT ≤70U/L, had HR 1.82 (1.48-2.24), p<0.001. For cause-specific mortality, lower ALT was associated with a higher risk of cardiovascular death only, whereas GGT >70U/L was associated with higher risks of death due to cardiovascular disease, cancer and non-cancer/non-cardiovascular causes. The relationship for ALT persisted after adjustment for indirect measures of frailty but was attenuated by elevated hsCRP.

CONCLUSIONS

As in the general population, ALT has a negative, and GGT a positive, correlation with mortality in type 2 diabetes when ALT is less than two times the upper limit of normal. The relationship for ALT appears specific for death due to cardiovascular disease. Links of low ALT with frailty, as a potential mechanism for relationships seen, were neither supported nor conclusively refuted by our analysis and other factors are also likely to be important in those with type 2 diabetes.

Outcome of hepatectomy for hepatocellular carcinoma in elderly patients with portal hypertension

The outcome of liver resection (LR) for elderly hepatocellular carcinoma (HCC) patients with portal hypertension (PHT) who may be excluded as liver transplantation candidates has not been fully evaluated. One hundred ninety-five patients who underwent initial curative LR for HCC with PHT were divided into 2 groups: age <70 years (n = 131) and age ≥70 years (n = 64). Clinicopathologic data and postoperative complications were compared. Preoperative characteristics and postoperative complications were similar in both groups. However, in-hospital mortality was significantly more frequent in elderly than in younger patients (11% versus 1%, P = 0.002). No significant intergroup differences were observed in the 5-year disease-free survival rate or recurrence rate (19.7% versus 17.2%; P = 0.338, 63% versus 56%; P = 0.339). Although LR for elderly HCC patients with PHT can be performed with curative intent and gives results comparable with those in younger patients, it is associated with higher in-hospital mortality.

Aging and liver disease

PURPOSE OF REVIEW

Aging is a condition in which a person gradually loses the ability to maintain homeostasis, due to structural alteration or dysfunction. Aging is a major risk factor for most chronic diseases. As the liver has a remarkable ability to regenerate, this review assessed the effect of aging on clinical liver disease with references to preclinical models when relevant to pathogenesis.

RECENT FINDINGS

Aging has been shown to not only enhance vulnerability to acute liver injury but also increase susceptibility of the fibrotic response. Aging is associated with the severity and poor prognosis of various liver diseases including nonalcoholic fatty liver disease, alcoholic liver disease, hepatitis C, and liver transplantation.

SUMMARY

Treatment of older patients with liver disease may require different or longer interventions. Transplantation of an older liver will be less tolerant of subsequent injury. Future studies are needed to understand more about the molecular mechanism of aging and contribute to the development of a noble treatment strategy that can block the progression of aging-induced liver diseases.

Hepatectomy is a reasonable option for older patients with hepatocellular carcinoma

BACKGROUND

Hepatic resection is the main treatment for patients with hepatocellular carcinoma. However, surgery is generally stressful for older patients.

METHODS

Clinicopathologic data and outcomes after hepatic resection were retrospectively investigated for older patients with hepatocellular carcinoma. The younger group (n = 219) included patients aged 60 to 69 years, and the older group (n = 60) included patients >70 years of age.

RESULTS

Hepatitis B virus was more common in the younger group than in the older group (64.5% vs 28.8%, P < .001). The occurrence of pneumonia was higher in older group than in the younger group (10.0% vs 2.3%, P = .015), but postoperative complications and mortality were not significantly different between the 2 groups. There was no statistically significant difference in disease-free survival rates between the 2 groups.

CONCLUSIONS

Although the incidence of postoperative pneumonia was higher in the older group than in the younger group, hepatic resection was justified for hepatocellular carcinoma in selected patients >70 years of age.

Effect of donor age on graft function and long-term survival of recipients undergoing living donor liver transplantation

BACKGROUND

Donor shortage is the biggest obstacle in organ transplantation. Living donor liver transplantation (LDLT) has been considered as a valuable approach to shortening waiting time. The objectives of this study were to investigate the feasibility of utilizing donors older than 50 years in LDLT and to evaluate the graft function and recipient survival.

METHODS

All LDLT cases (n=159) were divided into the older (donor age≥50 years, n=10) and younger (donor age<50 years, n=149) donor groups. Donor graft and recipient condition pre-, intra- and post-operation were compared between the two groups. In particular, graft functions and recipient survivals were analyzed.

RESULTS

The median donor age was 58.5 (52.5-60.0) years in the older donor group and 25.0 (23.0-32.0) in the younger donor group. There was no significant difference in cold ischemic time, anhepatic phase and operation time between the older and younger donor groups (P>0.05). However, the volume of red blood cell transfused in operation was greater in the older donor group than in the younger donor group (1900 vs 1200 mL, P=0.023). The 1-, 3- and 5-year graft survival rates were 90%, 80% and 80% for the older donor group, and 92%, 87% and 87% for the younger donor group, respectively (P=0.459). The 1-, 3- and 5-year survival rates were 100%, 90% and 90% for recipients with older grafts, and 93%, 87% and 87% for those with younger grafts, respectively (P=0.811).

CONCLUSION

It is safe for a LDLT recipient to receive liver from donors older than 50 years, and there is no significant adverse effect on graft function and long-term patients' survival.

Comparison of Tc-99m GSA scintigraphy and CT volumetry for evaluation in portal vein embolization

PURPOSE

To determine the correlation of the rate of change of each future remnant liver (FRL) before and after portal vein embolization (PVE), by CT volumetry and Tc-99m galactosyl human serum albumin scintigraphy (GSA scintigraphy).

MATERIAL AND METHODS

From December 2007 to July 2012, ten patients underwent PVE before hepatic resection. CT volumetry and GSA scintigraphy were performed before and after PVE. The FRL was divided at Cantlie's line for CT volumetry, and volume change rates before and after PVE were calculated. The maximum removal rate (Rmax) was calculated using a radiopharmacokinetic model in GSA scintigraphy. The FRL Rmax change rates before and after PVE were calculated. The correlation between the volume change rates and the Rmax change rates was analyzed.

RESULTS

The FRL volume change rate was 1.28 ± 0.26 (mean ± SD); the FRL hypertrophied in all patients significantly (p = 0.005). The FRL Rmax change rate was 1.66 ± 0.75; excluding one patient, there was significant FRL Rmax increase (p = 0.022). Although both increased significantly, no correlation between the volume change rate and the Rmax change rate was observed.

CONCLUSION

No correlation was observed between the FRL volume rate and the Rmax rate.

Older patient age may predict early mortality after transjugular intrahepatic portosystemic shunt creation in individuals at intermediate risk

PURPOSE

To identify prognostic factors for early mortality among patients with intermediate-risk Model for End-stage Liver Disease (MELD) scores undergoing transjugular intrahepatic portosystemic shunt (TIPS) creation.

MATERIALS AND METHODS

In this single-institution retrospective study, 47 patients (31 men; mean age, 54 y) with intermediate MELD scores (ie, 18-25) underwent TIPS creation between 1999 and 2012. Medical records were reviewed to identify demographic (age, sex), liver disease (Child-Pugh, MELD), and procedure data (indication, urgency, stent type, portosystemic pressure gradient reduction, complications), and the influence of these parameters on 90-day mortality was assessed by multivariate binary logistic regression analysis.

RESULTS

TIPSs were successfully created for variceal hemorrhage (n = 24), ascites (n = 17), hydrothorax (n = 5), and portal vein thrombosis (n = 1). Hemodynamic success rate was 94% (44 of 47), and mean portosystemic pressure gradient reduction was 13 mm Hg. The 90-day mortality rate was 36% (17 of 47). Patient age (P = .026) was significantly associated with 90-day mortality. Mean ages of living versus dead patients were 51 and 60 years, and mortality rates in patients aged 54 years or younger versus 55 years or older were 21% (five of 24) and 52% (12 of 23), respectively. There was no difference in MELD scores between these age groups (20.6 vs 21.0; P = .600), and MELD score was not a predictive factor on regression analysis.

CONCLUSIONS

Age is a prognostic factor for early mortality in TIPS recipients with intermediate MELD scores. Mortality rates are higher in patients at least 55 years of age, but MELD score does not predict survival in this subset. Age should be contemplated when selecting patients at intermediate risk for TIPS creation.

The role of CUGBP1 in age-dependent changes of liver functions

Aging liver is characterized by alterations of liver biology and by a reduction of many functions which are important for the maintenance of body homeostasis. The main dysfunctions include appearance of enlarged hepatocytes, impaired liver regeneration after partial hepatectomy (PH), development of hepatic steatosis, reduction of secretion of proteins and alterations in the hepatic sinusoid. RNA binding proteins are involved in the regulation of gene expression in all tissues including regulation of biological processes in the liver. This review is focused on the role of a conserved, multi-functional RNA-binding protein, CUGBP1, in the development of aging phenotype in the liver. CUGBP1 has been identified as a protein which binds to RNA CUG repeats expanded in Myotonic Dystrophy type 1 (DM1). CUGBP1 is highly expressed in the liver and regulates translation of proteins which are critical for maintenance of liver functions. In livers of young mice, CUGBP1 forms complexes with eukaryotic translation initiation factor eIF2 and supports translation of C/EBPβ and HDAC1 proteins, which are involved in liver growth, differentiation and liver cancer. Aging changes several signaling pathways which lead to the elevation of the CUGBP1-eIF2α complex and to an increase of translation of C/EBPβ and HDAC1. These proteins form multi-protein complexes with additional transcription factors and with chromatin remodeling proteins causing epigenetic alterations of gene expression in livers of old mice. It appears that CUGBP1-mediated translational elevation of HDAC1 is one of the key events in the epigenetic changes in livers of old mice, leading to the development of age-associated dysfunctions of the liver. This review will also discuss a possible role of CUGBP1 in liver dysfunction in patients affected with DM1.

Serum levels of alanine aminotransferase decrease with age in longitudinal analysis

BACKGROUND & AIMS

An increased level of alanine aminotransferase (ALT) is a marker of liver injury. The mean ALT level has been reported to decrease with age; we performed a longitudinal analysis to determine whether serum levels of ALT changes with age among community-dwelling, older adults in the US.

METHODS

We analyzed clinical data from 2 cohorts of individuals who participated in the Rancho Bernardo Study, in Southern CA. The first cohort comprised 1073 community-dwelling participants (59% women); clinical data was collected from 1984-1987 and 1992-1997. The second cohort comprised 416 participants (64% women); data was collected from 1984-1987, 1992-1997, and 1997-1999. Demographic, metabolic covariates, ALT, bilirubin, and albumin were measured. Changes in individual ALT over time were examined in unadjusted and multivariable-adjusted linear and logistic regression analyses.

RESULTS

At the baseline visit, the patients' mean age was 65.7 years and body mass index was 24.9 kg/m(2). In cohort 1, the mean levels of ALT decreased with age by 10% (from 21 to 19 IU/L) between the time periods of 1984-1987 and 1992-1997 (P < .0001). In cohort 2, they decreased by 20% (from 20 to 16 IU/L) between the time periods of 1984-1987 and 1997-1999 (P < .0001). Categorically-defined increases in ALT also decreased with age (P < .0001). Results remained consistent in sex-specific analyses and after adjusting for metabolic syndrome components, alcohol use, bilirubin, and serum levels of albumin (P < .0001).

CONCLUSIONS

In a longitudinal analysis, we observed that levels of ALT decrease with age, independent of sex, metabolic factors, alcohol use, and results from commonly used liver function tests (bilirubin and albumin). When interpreting serum levels of ALT, physicians should consider patients' age especially in the elderly.

Alanine aminotransferase decreases with age: the Rancho Bernardo Study

Background

Serum alanine aminotransferase (ALT) is a marker of liver injury. The 2005 American Gastroenterology Association Future Trends Committee report states that serum ALT levels remain constant with age. This study examines the association between serum ALT and age in a community-dwelling cohort in the United States.

Methods

A cross-sectional study of 2,364 (54% female) participants aged 30–93 years from the Rancho Bernardo Study cohort who attended a research clinic visit in 1984–87. Demographic, metabolic co-variates, ALT, bilirubin, gamma glutamyl transferase (GGT), albumin, and adiposity signaling biomarkers (leptin, IL-6, adiponectin, ghrelin) were measured. Participants were divided into four-groups based upon age quartile, and multivariable-adjusted least squares of means (LSM) were examined (p for trend <0.05).

Results

ALT decreased with increasing age, with mean ALT levels (IU/L) of 23, 21, 20, and 17 for those between quartile ages 30–62, 63–71, 72–77, and 78–93 years (p<0.0001). Trends of decreasing LSM ALT with age and the decreasing prevalence of categorically defined elevated serum ALT with age remained robust after adjusting for sex, alcohol use, metabolic syndrome components, and biomarkers of adiposity (p-value <0.0001), and was not materially changed after adjusting for bilirubin, GGT, and albumin.

Conclusions

ALT levels decrease with age in both men and women independent of metabolic syndrome components, adiposity signaling biomarkers, and other commonly used liver function tests. Further studies are needed to understand the mechanisms responsible for a decline in ALT with age, and to establish the optimal cut-point of normal ALT in the elderly.

Specific metabolic rates of major organs and tissues across adulthood: evaluation by mechanistic model of resting energy expenditure

BACKGROUND

The specific resting metabolic rates (K(i); in kcal · kg(-1 )· d(-1)) of major organs and tissues in adults were suggested by Elia (in Energy metabolism: tissue determinants and cellular corollaries. New York, NY: Raven Press, 1992) to be as follows: 200 for liver, 240 for brain, 440 for heart and kidneys, 13 for skeletal muscle, 4.5 for adipose tissue, and 12 for residual organs and tissues. However, Elia's K(i) values have never been fully evaluated.

OBJECTIVES

The objectives of the present study were to evaluate the applicability of Elia's K(i) values across adulthood and to explore the potential influence of age on the K(i) values.

DESIGN

A new approach was developed to evaluate the K(i) values of major organs and tissues on the basis of a mechanistic model: REE = Σ(K(i) × T(i)), where REE is whole-body resting energy expenditure measured by indirect calorimetry, and T(i) is the mass of individual organs and tissues measured by magnetic resonance imaging. With measured REE and T(i), marginal 95% CIs for K(i) values were calculated by stepwise univariate regression analysis. An existing database of nonobese, healthy adults [n = 131; body mass index (in kg/m²) <30] was divided into 3 age groups: 21-30 y (young, n = 43), 31-50 y (middle-age, n = 51), and > 50 y (n = 37).

RESULTS

Elia's K(i) values were within the range of 95% CIs in the young and middle-age groups. However, Elia's K(i) values were outside the right boundaries of 95% CIs in the >50-y group, which indicated that Elia's study overestimated K(i) values by 3% in this group. Age-adjusted K(i) values for adults aged >50 y were 194 for liver, 233 for brain, 426 for heart and kidneys, 12.6 for skeletal muscle, 4.4 for adipose tissue, and 11.6 for residuals.

CONCLUSION

The general applicability of Elia's K(i) values was validated across adulthood, although age adjustment is appropriate for specific applications.

Relationship of hepatic functional parameters with changes of functional liver volume using technetium-99m galactosyl serum albumin scintigraphy in patients undergoing preoperative portal vein embolization: a follow-up report

BACKGROUND

To identify predictors of changes in functional hepatic volumes after portal vein embolization (PVE) before hepatectomy, we examined the relationship between hepatic functional parameters and changes in functional volume of the embolized and non-embolized liver based on a previous volumetric analysis.

MATERIAL AND METHODS

Subjects were 24 patients who underwent PVE, which was performed through the trans-ileocolic vein (n = 4) or by percutaneous transhepatic puncture (n = 20). The RI liver volume parameter was measured by liver scintigraphy with technetium-(99m) galactosyl human serum albumin ((99m)Tc-GSA). Computed tomography (CT) volume parameter was also measured.

RESULTS

Significant atrophy of the embolized liver and hypertrophy of the non-embolized liver (change of 72 ± 108 cm(3) and 111 ± 91 cm(3), respectively) (change of 7.8%) was observed after PVE. The change in these RI volume parameters (change of 173 ± 175 cm(3) and 145 ± 137 cm(3) , respectively) (16.5%) was significantly greater than CT volume parameters (P < 0.01). CT vol and RI vol in the embolized and non-embolized liver were well correlated (r = 0.75 and 0.69, respectively). However, the correlation between CT and RI volume parameters in the embolized and non-embolized liver after PVE was very weak (r = 0.17 and 0.03, respectively). Only alkaline phosphatase level correlated negatively with atrophic CT volume parameter of the embolized liver (r = -0.455, P < 0.05). When compared with CT volume parameter, more parameters were significantly correlated with changes of RI volume parameter in the embolized liver: pre-PVE pressure; ICGR15; and serum levels of hyaluronate, total bilirubin, albumin, and alkaline phosphatase. Only platelet count was significantly correlated with hypertrophy of the non-embolized liver.

CONCLUSION

RI volume parameter might more accurately reflect functional changes in the embolized liver and non-embolized liver than CT volume parameter. Correlated parameters might allow us to predict the functional effect of PVE.

Outcome of acute liver failure in the elderly

Older age is considered a poor prognostic factor in acute liver failure (ALF) and may still be considered a relative contraindication for liver transplantation for ALF. We aimed to evaluate the impact of older age, defined as age > or = 60 years, on outcomes in patients with ALF. One thousand one hundred twenty-six consecutive prospective patients from the US Acute Liver Failure Study Group registry were studied. The median age was 38 years (range, 15-81 years). One thousand sixteen patients (90.2%) were younger than 60 years (group 1), and 499 (49.1%) of these had acetaminophen-induced ALF; this rate of acetaminophen-induced ALF was significantly higher than that in patients > or = 60 years (group 2; n = 110; 23.6% with acetaminophen-induced ALF, P < 0.001). The overall survival rate was 72.7% in group 1 and 60.0% in group 2 (not significant) for acetaminophen patients and 67.9% in group 1 and 48.2% in group 2 for non-acetaminophen patients (P < 0.001). The spontaneous survival rate (ie, survival without liver transplantation) was 64.9% in group 1 and 60.0% in group 2 (not significant) for acetaminophen patients and 30.8% in group 1 and 24.7% in group 2 for non-acetaminophen patients (P = 0.27). Age was not a significant predictor of spontaneous survival in multiple logistic regression analyses. Group 2 patients were listed for liver transplantation significantly less than group 1 patients. Age was listed as a contraindication for transplantation in 5 patients. In conclusion, in contrast to previous studies, we have demonstrated a relatively good spontaneous survival rate for older patients with ALF when it is corrected for etiology. However, overall survival was better for younger non-acetaminophen patients. Fewer older patients were listed for transplantation.

Predicting liver failure following major hepatectomy

Pre-operative determination of the risk of liver dysfunction has come under criticism with regards to its usefulness in clinical practice. Opinion is split between centres which use such tests uniformly on all patients and those where clinical judgment alone is used. Published data would not suggest any difference in mortality, morbidity or liver failure rates between these groups. This review outlines and presents the evidence for pre-operative quantification of functional liver remnant volume.

Hepatic resection is justified for elderly patients with hepatocellular carcinoma

BACKGROUND

Hepatic resection is one of the main treatment modalities for patients with hepatocellular carcinoma (HCC); however, surgery is generally stressful and often is avoided for elderly patients. This retrospective study was designed to determine whether the indications for hepatic resection in younger patients with HCC are applicable to elderly patients.

METHODS

Subjects were 294 patients in whom 319 hepatic resections were performed for HCC (male/female ratio, 238/81; age range, 18-83 years). The patients were divided into two groups according to age at the time of surgery: 70 years or older (n = 109) and 69 years or younger (n = 210). Surgical strategy and postoperative follow-up methods did not differ between groups. The incidence and severity of postoperative complications classified by the Clavien system were compared between the two groups. Postoperative survival was compared between the two groups and between subgroups based on Japan Integrated Staging (JIS) scores. HCC-related death rates also were compared.

RESULTS

No significant between-group difference was found in background liver function or type of hepatic resection. Differences were found in performance status and type of hepatitis virus infection. No difference was observed in the incidence or severity of postoperative complications. Postoperative survival was similar between the two age-based study groups and between the JIS-based subgroups. HCC-related death rates did not differ between groups.

CONCLUSIONS

The absence of differences in postoperative outcomes between groups suggests that hepatic resection is justified for HCC in selected patients aged 70 years or older.

Assessment of liver graft function and regeneration by galactosyl-human serum albumin (99mTc-GSA) liver scintigraphy in adult living-donor liver transplantation

BACKGROUND

In adult living-donor liver transplantation (LDLT), the assessment of the graft functional reserve is very important. We evaluated the graft functional reserve by technetium-99m-diethylenetriaminepenta-acetic acid-galactosyl-human serum albumin ((99m)Tc-GSA) liver scintigraphy.

PATIENTS AND METHOD

From May 2003 to September 2006, (99m)Tc-GSA studies were performed in 27 adult recipients on two, four wk after LDLT, the receptor index [ratio of liver to heart-plus-liver radioactivity at 15 minutes (LHL15)] (LHL15) was calculated. Recipients were divided into two groups according to LHL15 on two wk after LDLT (group H; >0.935, group L; <0.935). Liver functional tests and recipients' background parameters were evaluated between the two groups.

RESULT

Group L accompanied higher preoperative model for end-stage liver disease (MELD) score (p = 0.038), lower graft-recipient weight ratio (GRWR) (p = 0.032) and older donor age (p = 0.003) compared with group H. There was no significant difference in the graft regeneration rate between two groups. The three-yr cumulative survival rate was 76.1% in group L and 88.9% in group H.

CONCLUSION

In LDLT, LHL15 has the potential to assess the graft function and predict the recipients' outcome. Graft function after LDLT may be related closely to the pretransplant MELD score, GRWR, and donor age.