ALT Levels for Asians With Metabolic Diseases: A Meta-analysis of 86 Studies With Individual Patient Data Validation

Alanine aminotransferase as a risk marker for new-onset metabolic dysfunction-associated fatty liver disease

In this editorial, we comment on the article by Chen et al. Metabolic dysfunction-associated fatty liver disease (MAFLD) is a global public health burden whose incidence has risen concurrently with overweight and obesity. Given its detrimental health impact, early identification of at-risk individuals is crucial. MAFLD diagnosis is based on evidence of hepatic steatosis indicated by liver biopsy, imaging, or blood biomarkers, and one of the following conditions: Overweight/ obesity, type 2 diabetes mellitus, or metabolic dysregulation. However, in large-scale epidemiological studies, liver biopsies are not feasible. The application of techniques such as ultrasonography, computed tomography, magnetic resonance imaging, and magnetic resonance spectroscopy is restricted by their limited sensitivity, low effectiveness, high costs, and need for specialized software. Blood biomarkers offer several advantages, particularly in large-scale epidemiological studies or clinical scenarios where traditional imaging techniques are impractical. Analysis of cumulative effects of excess high-normal blood alanine aminotransferase (ALT) levels of blood ALT levels could facilitate identification of at-risk patients who might not be detected through conventional imaging methods. Accordingly, investigating the utility of blood biomarkers in MAFLD should enhance early detection and monitoring, enabling timely intervention and management and improving patient outcomes.

The incidence of adverse outcome in donors after living donor liver transplantation: A meta-analysis of 60,829 donors

The scarcity of liver grafts has prompted developments in living donor liver transplantations (LDLT), with previous literature illustrating similar outcomes in recipients compared to deceased donor transplants. However, significant concerns regarding living donor morbidity and mortality have yet to be examined comprehensively. This study aims to provide estimates of the incidence of various outcomes in living liver donors. In this meta-analysis, Medline and Embase were searched from inception to July 2022 for articles assessing the incidence of outcomes in LDLT donors. Complications in the included studies were classified into respective organ systems. Analysis of incidence was conducted using a generalized linear mixed model with Clopper-Pearson intervals. Eighty-seven articles involving 60,829 living liver donors were included. The overall pooled incidence of complications in LDLT donors was 24.7% (CI: 21.6%-28.1%). The incidence of minor complications was 17.3% (CI: 14.7%-20.3%), while the incidence of major complications was lower at 5.5% (CI: 4.5%-6.7%). The overall incidence of donor mortality was 0.06% (CI: 0.0%-0.1%) in 49,027 individuals. Psychological complications (7.6%, CI: 4.9%-11.5%) were the most common among LDLT donors, followed by wound-related (5.2%, CI: 4.4%-6.2%) and respiratory complications (4.9%, CI: 3.8%-6.3%). Conversely, cardiovascular complications had the lowest incidence among the subgroups at 0.8% (CI: 0.4%-1.3%). This study presents the incidence of post-LDLT outcomes in living liver donors, illustrating significant psychological, wound-related, and respiratory complications. While significant advancements in recent decades have contributed towards decreased morbidity in living donors, our findings call for targeted measures and continued efforts to ensure the safety and quality of life of liver donors post-LDLT.

Upper limit of normal ALT levels in health and metabolic diseases: Pooled analysis of 423,355 individuals with bootstrap modelling

INTRODUCTION

Given the global rise in obesity-related metabolic diseases, the upper limit of normal (ULN) alanine aminotransferase (ALT) in individuals with and without metabolic diseases may have changed. We performed a meta-analysis combined with bootstrap modelling to estimate the ALT ULN levels for individuals with and without metabolic diseases.

METHODS AND RESULTS

Two separate searches of the PubMed, Embase and Cochrane databases were performed, one to identify healthy individuals which yielded 12 articles (349,367 individuals); another to include those with potential metabolic diseases but without known liver disease which yielded 35 articles (232,388 individuals). We estimated the mean ALT using a random-effects mixed model and the ULN level (95th-percentile value) via a bootstrap model with 10,000 resamples. In individuals without metabolic diseases and known liver disease, the ALT ULN levels were 32 U/L overall; 36 U/L in males and 28 U/L in females. In analyses that included individuals with metabolic diseases, the ALT ULN levels were 40 U/L among the overweight/obese (29 U/L if normal weight) and 36 U/L among those with type 2 diabetes mellitus (T2DM) (33 U/L if no T2DM). On meta-regression of study-level factors, body mass index (coefficient 1.49, 95% CI 0.11-2.86, p = 0.03), high-density lipoprotein (coefficient -0.47, 95% CI -0.85-(-0.08), p = 0.02) and triglycerides (coefficient 0.19, 95% CI 0.12-0.25, p < 0.0001) correlated with ALT.

CONCLUSION

We provide expected ranges of ALT ULN levels for individuals without known liver disease without metabolic diseases and those with or without T2DM and/or are normal weight or overweight/obese. These data may have implications for clinical care and screening.

Cumulative effects of excess high-normal alanine aminotransferase levels in relation to new-onset metabolic dysfunction-associated fatty liver disease in China

BACKGROUND

Within the normal range, elevated alanine aminotransferase (ALT) levels are associated with an increased risk of metabolic dysfunction-associated fatty liver disease (MAFLD).

AIM

To investigate the associations between repeated high-normal ALT measurements and the risk of new-onset MAFLD prospectively.

METHODS

A cohort of 3553 participants followed for four consecutive health examinations over 4 years was selected. The incidence rate, cumulative times, and equally and unequally weighted cumulative effects of excess high-normal ALT levels (ehALT) were measured. Cox proportional hazards regression was used to analyse the association between the cumulative effects of ehALT and the risk of new-onset MAFLD.

RESULTS

A total of 83.13% of participants with MAFLD had normal ALT levels. The incidence rate of MAFLD showed a linear increasing trend in the cumulative ehALT group. Compared with those in the low-normal ALT group, the multivariate adjusted hazard ratios of the equally and unequally weighted cumulative effects of ehALT were 1.651 [95% confidence interval (CI): 1.199-2.273] and 1.535 (95%CI: 1.119-2.106) in the third quartile and 1.616 (95%CI: 1.162-2.246) and 1.580 (95%CI: 1.155-2.162) in the fourth quartile, respectively.

CONCLUSION

Most participants with MAFLD had normal ALT levels. Long-term high-normal ALT levels were associated with a cumulative increased risk of new-onset MAFLD.

Meta-analysis: Prevalence and impact of alcohol abstinence in alcohol-associated cirrhosis

BACKGROUND

Although alcohol abstinence may be an effective intervention for alcohol-associated cirrhosis, its association with prognosis has not been systematically assessed or quantified.

AIMS

To determine the prevalence of alcohol abstinence, factors associated with alcohol abstinence and the impact of abstinence on morbidity and overall survival in people with alcohol-associated cirrhosis.

METHODS

We searched Medline and Embase from inception to 15 April 2023 for prospective and retrospective cohort studies describing alcohol abstinence in people with known alcohol-associated cirrhosis. Meta-analysis of proportions for pooled estimates was performed. The method of inverse variance, employing a random-effects model, was used to pool the hazard ratio (HR) comparing outcomes of abstinent against non-abstinent individuals with alcohol-associated cirrhosis.

RESULTS

We included 19 studies involving 18,833 people with alcohol-associated cirrhosis. The prevalence of alcohol abstinence was 53.8% (CI: 44.6%-62.7%). Over a mean follow-up duration of 48.6 months, individuals who continued to consume alcohol had significantly lower overall survival compared to those who were abstinent (HR: 0.611, 95% CI: 0.506-0.738). These findings remained consistent in sensitivity/subgroup analysis for the presence of decompensation, study design and studies that assessed abstinence throughout follow-up. Alcohol abstinence was associated with a significantly lower risk of hepatic decompensation (HR: 0.612, 95% CI: 0.473-0.792).

CONCLUSIONS

Alcohol abstinence is associated with substantial improvement in overall survival in alcohol-associated cirrhosis. However, only half of the individuals with known alcohol-associated cirrhosis are abstinent.

Air pollution impede ALT normalization in chronic hepatitis B patients treated with nucleotide/nucleoside analogues

Biochemical response is an important prognostic indicator in chronic hepatitis B (CHB) patients receiving nucleotide/nucleoside analogues (NAs). However, the effects of air pollution in alanine aminotransferase (ALT) normalization remain elusive. This longitudinal study recruited 80 hepatitis B e antigen-negative CHB patients who received NAs. ALT levels were measured during the first year of anti-hepatitis B virus therapy. Normal ALT levels were defined as <19 U/L for females and <30 U/L for males, and the risk factors associated with ALT abnormalities were analyzed. The daily estimations of air pollutants (particulate matter ≤2.5 µm in diameter (PM2.5), nitrogen dioxide, ozone (O3), and benzene) were aggregated into the mean estimation for the previous month based on the date of recruitment (baseline) and 1 year later. Sixteen patients (20.0%) had a baseline ALT > 40 U/L; overall, 41 (51.6%) had an abnormal ALT (≥19 U/L for females and ≥ 30 U/L for males). After 1 year of NA therapy, 75 patients (93.8%) had undetectable hepatitis B virus DNA levels. Mean post-treatment ALT levels were significantly lower than mean pretreatment levels (21.3 vs 30.0 U/L, respectively; P < .001). The proportion of patients with a normal ALT was also significantly higher after versus before treatment (71.2% vs 51.2%, respectively; P = .001). The strongest factors associated with ALT abnormality after 1 year of NA treatment were body mass index (odds ratio [OR], 1.28; 95% confidence interval [CI], 1.05-1.54; P = .01) and ozone level (OR, 1.11; 95% CI, 1.02-1.22; P = .02). Among hepatitis B e antigen-negative CHB patients with relatively low viral loads, 1 year of NA treatment improved ALT levels after the adjustment for confounding factors and increased the proportion of patients with normal ALT levels. Air pollution affects the efficacy of ALT normalization.

Transitioning from having no metabolic abnormality nor obesity to metabolic impairment in a cohort of apparently healthy adults

INTRODUCTION

The global prevalence of metabolic syndrome and its association with increased morbidity and mortality has been rigorously studied. However, the true prevalence of "metabolic health", i.e. individuals without any metabolic abnormalities is not clear. Here, we sought to determine the prevalence of "metabolically healthy" individuals and characterize the "transition phase" from metabolic health to development of dysfunction over a follow-up period of 5 years.

METHODS

We included 20,507 individuals from the Tel Aviv Sourasky Medical Center Inflammation Survey (TAMCIS) which comprises apparently healthy individuals attending their annual health survey. A second follow-up visit was documented after 4.8 (± 0.6) years. We defined a group of metabolically healthy participants without metabolic abnormalities nor obesity and compared their characteristics and change in biomarkers over time to participants who developed metabolic impairment on their follow-up visit. The intersections of all metabolic syndrome components and elevated high sensitivity C-reactive protein (hs-CRP) were also analyzed.

RESULTS

A quarter of the cohort (5379 individuals, (26.2%) did not fulfill any metabolic syndrome criteria during their baseline visit. A total of 985 individuals (12.7% of returning participants) developed metabolic criteria over time with hypertension being the most prevalent component to develop among these participants. Individuals that became metabolically impaired over time demonstrated increased overlap between metabolic syndrome criteria and elevated hs-CRP levels. The group that became metabolically impaired over time also presented higher delta values of WBC, RBC, liver biomarkers, and uric acid compared with participants who were consistently metabolically impaired. LDL-C (low-density lipoprotein cholesterol) delta levels were similar.

CONCLUSIONS

Roughly one-quarter of apparently healthy adults are defined as "metabolically healthy" according to current definitions. The transition from health to metabolic dysfunction is accompanied with active inflammation and several non-metabolic syndrome biomarkers. Aggressive screening for these biomarkers, blood pressure and hs-CRP might help identify apparently healthy individuals at increased risk of developing metabolic syndrome over time.

Hepatocellular Carcinoma Incidence in Alcohol-Associated Cirrhosis: Systematic Review and Meta-analysis

BACKGROUND & AIMS

Alcohol is one of the leading causes of hepatocellular carcinoma (HCC). However, pooled estimates of HCC incidence in alcohol-associated cirrhosis have not been evaluated systematically. We performed a pooled analysis of time-to-event data to provide robust estimates for the incidence of HCC in alcohol-associated cirrhosis.

METHODS

Medline, Embase, Cochrane Central Register, Scopus, and Web of Science were searched from inception to August 2021. Individual patient data were reconstructed from published Kaplan-Meier curves, and a pooled analysis of cumulative HCC incidence was performed using a random-effects model.

RESULTS

We screened 5022 articles and included 18 studies (148,333 patients). In the pooled analysis, the cumulative incidence of HCC in alcohol-associated cirrhosis at 1, 5, and 10 years among studies that accounted for the competing risk of death without HCC was 1%, 3%, and 9%, respectively. A secondary analysis by traditional meta-analysis determined that the HCC incidence rate was higher in cohorts enrolled in a HCC surveillance program (18.6 vs 4.8 per 1000 person-years; P = .001) vs those who were not enrolled in a surveillance program. Meta-regression showed that diabetes, smoking, variceal bleeding, and hepatic decompensation were associated with a higher risk of HCC.

CONCLUSIONS

Our analysis determined that the 5- and 10- year cumulative risk of HCC in alcohol-associated cirrhosis was 3% and 9%, respectively, with a higher incidence in cohorts that were enrolled in a HCC surveillance program. These data should be validated further in large prospective studies, and may have important implications for HCC screening and surveillance among patients with alcohol-associated cirrhosis.

Poor Diagnostic Efficacy of Noninvasive Tests for Advanced Fibrosis in Obese or Younger Than 60 Diabetic NAFLD patients

BACKGROUND & AIMS

Serum-based noninvasive tests (NITs) have been widely used to assess liver fibrosis in patients with nonalcoholic fatty liver disease (NAFLD). However, the diagnostic efficacy of NITs across ranges of age, body mass index (BMI), and presence of type 2 diabetes (T2DM) may vary and have not been well-characterized.

METHODS

We analyzed 1489 patients with biopsy-proven NAFLD from 6 centers in Japan, Taiwan, and Korea. Using histology as the gold standard, we compared the areas under the receiver operating characteristic (AUROCs) of Fibrosis-4 index (FIB-4), NAFLD fibrosis score (NFS), and the new Hepamet fibrosis score (HFS), with a focus on performance in subgroups as stratified by age, BMI, and the presence of T2DM.

RESULTS

By histology, 44.0% of the overall cohort (655/1489) had F2-4, and 20.6% (307/1489) had F3-4 fibrosis. FIB-4 had the highest AUROCs for both F2-4 (0.701 vs NFS 0.676 and HFS 0.682, P = .001) and F3-4 (0.767 vs NFS 0.736 and HFS 0.752, P = .002). However, for F3-4 fibrosis, the AUROCs of all 3 NITs were generally higher in older (>60 years), nonobese (BMI <25 kg/m²), and non-diabetic patients, although overall the best performance was observed with FIB-4 among nonobese (BMI<25) diabetic patients (AUROC, 0.92). The worst performance was observed in younger patients with T2DM for all NITs including FIB-4 (AUROC, 0.63-0.66).

CONCLUSIONS

FIB-4 had higher diagnostic efficacy for F3-4 than NFS or HFS, but this varied greatly by age, BMI, and T2DM, with better performance in older, nonobese, and nondiabetic patients. However, all NITs including FIB-4 had unacceptably poor performance in young or obese diabetic patients.

An Observational Data Meta-analysis on the Differences in Prevalence and Risk Factors Between MAFLD vs NAFLD

BACKGROUND & AIMS

The shift to redefine nonalcoholic fatty liver disease (NAFLD) as metabolic associated fatty liver disease (MAFLD) can profoundly affect patient care, health care professionals, and progress within the field. To date, there remains no consensus on the characterization of NAFLD vs MAFLD. Thus, this study sought to compare the differences between the natural history of NAFLD and MAFLD.

METHODS

Medline and Embase databases were searched to include articles on prevalence, risk factors, or outcomes of patients with MAFLD or NAFLD. Meta-analysis of proportions was conducted using the generalized linear mix model. Risk factors and outcomes were evaluated in conventional pairwise meta-analysis.

RESULTS

Twenty-two articles involving 379,801 patients were included. Pooled prevalence of MAFLD was 39.22% (95% confidence interval [CI], 30.96%-48.15%) with the highest prevalence in Europe and Asia, followed by North America. The current MAFLD Definition only accounted for 81.59% (95% CI, 66.51%-90.82%) of NAFLD diagnoses. Patients had increased odds of being diagnosed with MAFLD compared with NAFLD (odds ratio, 1.37; 95% CI, 1.16-1.63; P < .001). Imaging modality resulted in a significantly higher odds of being diagnosed with MAFLD compared with NAFLD, but not biopsy. MAFLD was significantly associated with males, higher body mass index, hypertension, diabetes, lipids, transaminitis, and greater fibrosis scores compared with NAFLD.

CONCLUSIONS

There were stark differences in the prevalence and risk factors between MAFLD and NAFLD. However, in the use of the MAFLD Definition, a greater emphasis on the management of concomitant metabolic diseases and a collaborative effort is required to explore the complex pathophysiologic mechanisms underlying the disease.

Outcomes of Nonalcoholic Steatohepatitis After Liver Transplantation: An Updated Meta-Analysis and Systematic Review

BACKGROUND & AIMS

Nonalcoholic steatohepatitis (NASH) is the fastest growing indication of liver transplantation (LT) and is projected to be the leading cause of LT in the near future. The systemic pathogenesis of NASH increases risks of adverse clinical outcomes in patients with NASH receiving LT. Thus, this study aimed to conduct a time-dependent survival analysis between LT recipients with and without NASH using hazard ratios.

METHODS

A search was conducted on Medline and Embase databases for articles relating to LT outcomes for NASH recipients. A survival analysis was conducted of hazard ratios using the DerSimonian and Laird random-effects model with meta-regression. To account for censoring, survival data were reconstructed from published Kaplan-Meier curves and pooled to derive more accurate hazard estimates and all-cause mortality in NASH patients after LT. Pairwise meta-analysis was conducted to analyze secondary outcomes.

RESULTS

Fifteen studies involving 119,327 LT recipients were included in our analysis with a prevalence of NASH of 20.2% (95% CI, 12.9-30.2). The pooled 1-year, 5-year, and 10-year all-cause mortality in NASH patients after LT were 12.5%, 24.4%, and 37.9%, respectively. Overall survival was comparable between LT recipients for NASH vs non-NASH (hazard ratio, 0.910; 95% CI, 0.760 to 1.10; P = .34). Meta-regression showed that a higher model for end-stage liver disease score was associated with significantly worse overall survival in NASH compared with non-NASH after LT (95% CI, -0.0856 to -0.0181; P = .0026).

CONCLUSIONS

This study shows that patients undergoing LT for NASH cirrhosis have comparable complication rates, overall survival, and graft survival compared with non-NASH patients, although close monitoring may be indicated for those with higher model for end-stage liver disease scores.

A Meta-Analysis on the Global Prevalence, Risk factors and Screening of Coronary Heart Disease in Nonalcoholic Fatty Liver Disease

BACKGROUND & AIMS

Cardiovascular disease remains the leading cause of death in patients with nonalcoholic fatty liver disease (NAFLD). Studies examining the association of coronary heart disease (CHD) and NAFLD are cofounded by various cardiometabolic factors, particularly diabetes and body mass index. Hence, we seek to explore such association by investigating the global prevalence, independent risk factors, and influence of steatosis grade on manifestation of CHD among patients with NAFLD.

METHODS

Two databases, Embase and Medline, were utilized to search for articles relating to NAFLD and CHD. Data including, but not limited to, continent, diagnostic methods, baseline characteristics, prevalence of CHD, CHD severity, NAFLD severity, and risk factors were extracted.

RESULTS

Of the 38 articles included, 14 reported prevalence of clinical coronary artery disease (CAD) and 24 subclinical CAD. The pooled prevalence of CHD was 44.6% (95% confidence interval [CI], 36.0%-53.6%) among 67,070 patients with NAFLD with an odds ratio of 1.33 (95% CI, 1.21%-1.45%; P &lt; .0001). The prevalence of CHD was higher in patients with moderate to severe steatosis (37.5%; 95% CI, 15.0%-67.2%) than those with mild steatosis (29.6%; 95% CI, 13.1%-54.0%). The pooled prevalence of subclinical and clinical CAD was 38.7% (95% CI, 29.8%-48.5%) and 55.4% (95% CI, 39.6%-70.1%), respectively.

CONCLUSION

Steatosis was found to be related with CHD involvement, with moderate to severe steatosis related to clinical CAD. Early screening and prompt intervention for CHD in NAFLD are warranted for holistic care in NAFLD.

Placebo effect on progression and regression in NASH: Evidence from a meta-analysis

BACKGROUND AND AIMS

The evaluation of the natural history of NASH has been limited. Currently, liver biopsy remains the gold standard in the assessment of NASH. Placebo-controlled trials represent a controlled environment with paired biopsies for the evaluation of NASH. This meta-analysis thus seeks to quantify the change severity of NASH over time, with patients on placebo arms from randomized controlled trials (RCTs) to examine the natural history of NASH.

METHODS

A search was conducted to include NASH RCTs with placebo treatment arms. Primary outcomes were (1) the resolution of NASH without worsening of fibrosis, (2) two-point reduction in NAFLD activity score without worsening of fibrosis, and (3) at least one-point reduction in fibrosis. Generalized linear mix model was used to estimate pooled proportion and mean differences.

RESULTS

This meta-analysis of 43 RCTs included 2649 placebo-treated patients. The pooled estimate of NASH resolution and two-point NAFLD activity score reduction without worsening of fibrosis was 11.65% (95% CI: 7.98-16.71) and 21.11% (95% CI: 17.24-25.57). The rate of ≥1 stage reduction and progression of fibrosis was 18.82% (95% CI: 15.65-22.47) and 22.74% (CI: 19.63-26.17), respectively. Older age and African American ethnicity was associated with lower NASH resolution rate in placebo-treated patients.

CONCLUSIONS

Despite the absence of any pharmacological interventions, a significant proportion of patients in the placebo arm demonstrated improvements in liver histology, highlighting the possibility that NASH is a disease that can not only progress but regress spontaneously over time. Additionally, histologic response in placebo-treated patients is helpful in future design of phase 2B and phase 3 trials.

A systematic review and meta-analysis on the impact of pre-existing and new-onset atrial fibrillation on outcomes before and after liver transplantation

BACKGROUND AND AIMS

Atrial Fibrillation (AF) is the most commonly diagnosed cardiac arrhythmia. It is associated with significant morbidity and mortality, as it is a major risk factor for cerebral vascular accidents (CVA). Our aim was to determine the prevalence of pre-existing and new-onset AF among patients undergoing liver transplantation (LT) and its impact on post-transplant outcomes.

METHODS

Medline and Embase were searched. Single-arm analysis was conducted using the generalized linear mixed model to determine the prevalence of pre-existing and new-onset AF. Logistic regression was performed to analyze risk factors. Comparative meta-analysis in odds ratio was conducted for binary outcomes.

RESULTS

Twenty articles were included, with 17 studies on pre-existing AF, and 7 including data on new-onset AF post-LT. The prevalence of pre-existing AF was 3.3% (CI 2.3-4.7) (14 studies, 45,070 patients) in pooled analysis. Significantly higher prevalence of pre-existing AF patients from North America was noted when compared to Europe (4.5%, CI 3.4-5.8 vs 1.5%, CI 0.8-2.7; p = 0.001). Body mass index (BMI), history of hypertension, diabetes, coronary artery disease (CAD), and cerebrovascular accidents (CVA) were risk factors for pre-existing AF. Pre-existing AF was significantly associated with major adverse cardiac or cerebrovascular events (MACCE) postoperatively (OR 8.02, 95%CI 5.40-11.90, p < 0.001). New-onset AF post-LT had an incidence of 6.8% (CI 4.9-9.3), and was associated with increased risk of mortality (OR 2.31, 95% CI 1.76-3.02, p < 0.001) and graft failure (OR 2.98, CI 1.99-4.47, p < 0.001).

CONCLUSION

AF is relatively more common among patients undergoing LT compared to the general non-transplant population. Additionally, it is associated with adverse outcomes including MACCE, thus warranting clinical attention. Thorough cardiac assessment, and close surveillance of post-operative AF may be clinically prudent.

A Meta-Analysis and Systematic Review on the Global Prevalence, Risk Factors, and Outcomes of Coronary Artery Disease in Liver Transplantation Recipients

The shift in the changing etiology of cirrhosis requiring liver transplantation (LT) has resulted in an increasing prevalence of coronary artery disease (CAD) that can potentially impact post-LT outcomes. This systematic review and meta-analysis evaluates the prevalence of CAD, risk factors, and outcomes of patients diagnosed with CAD before LT. MEDLINE and EMBASE were searched for articles describing CAD in pre-LT patients. Meta-analysis of proportions using the generalized linear mix model was conducted to analyze the pooled prevalence of CAD in pre-LT patients. Associated risk factors for CAD in pre-LT patients and outcomes were evaluated in conventional pairwise meta-analysis. A total of 39 studies were included. The pooled prevalence of patients diagnosed with CAD before LT was 15.9% (95% CI, 9.8%-24.7%). Age, male sex, diabetes mellitus, hypertension, hyperlipidemia, smoking, nonalcoholic steatohepatitis, hepatitis B virus, and hepatocellular carcinoma were significantly associated with CAD. Patients from high-income countries especially North America, Europe, and South America, with the associated risk factors were at increased risk for CAD before LT. CAD before LT was associated with an increased odds of overall mortality (odds ratio [OR], 1.4; 95% confidence interval [CI], 1.4-1.4; P = 0.01) and cardiac-related mortality (OR, 1.2; 95% CI, 1.1-1.3; P = 0.03). A total of 48.7% of included articles considered the presence of cardiovascular risk factors for CAD screening. However, 10.3% of the studies screened for CAD in pre-LT patients via invasive coronary angiography only, without stress testing or risk stratification. This study demonstrates the high prevalence of CAD in pre-LT patients, associated risk factors, and outcomes. There is heterogeneity among guidelines and practice in screening for pre-LT CAD, and more studies are needed to establish consensus.

Global Prevalence, Risk Factors, and Outcomes of Depression After Liver Transplant: A Systematic Review and Meta-analysis

Background and aims

With existing literature focusing on general quality of life, the magnitude and impact of depression among recipients after liver transplantation (LT) is unclear. Hence, we aim to evaluate the prevalence, risk factors, and outcomes for recipient-related depression after LT.

Methods

Medline and Embase were searched. Single-arm analysis was pooled using the generalized linear mixed model, and logistic regression was performed to analyze risk factors. Pairwise comparative meta-analysis in odds ratio was conducted for binary outcomes.

Results

Of 1069 abstracts, 189 articles underwent full-text review before the inclusion of 48 articles. Pooled depression rate among 5170 recipients was 24.52% (confidence interval [CI]: 19.46%-30.41%). Depression was most prevalent in Asia compared with other geographical regions. Younger age at transplantation (P = .019) and university education (P = .051) were protective against depression. However, those transplanted for alcoholic liver disease (odds ratio: 1.14, CI: 1.10-1.18, P ≤ 0.001) were more likely to be depressed. Depression resulted in increased odds of mortality (odds ratio: 1.82, CI: 1.08-3.07, P = .04), graft loss (P = .03), and graft rejection (P = .01).

Conclusion

Depression is highly prevalent after LT and may be associated with increased mortality and poorer graft outcomes. More emphasis is needed on the screening of depression among higher risk recipients.

The Association of Plant-Based Diet With Cardiovascular Disease and Mortality: A Meta-Analysis and Systematic Review of Prospect Cohort Studies

Background: The association between plant-based diets and cardiovascular disease (CVD) remains poorly characterized. Given that diet represents an important and a modifiable risk factor, this study aimed to assess (1) the relationships between the impact of adherence to plant-based diets on cardiovascular mortality, incident CVD, and stroke; (2) if associations differed by adherence to healthful and less healthful plant-based diets.

Methods and Findings: MEDLINE and EMBASE databases were searched up to May 2021. Studies assessing CVD outcomes with relation to plant-based dietary patterns or according to plant-based dietary indices (PDI) were included. A meta-analysis of hazard ratios (HR) was conducted using DerSimonian and Laird random effects model. Thirteen studies involving 410,085 participants were included. Greater adherence to an overall plant-based dietary pattern was significantly associated with a lower risk of cardiovascular mortality (pooled HR: 0.92, 95% CI: 0.86–0.99 p = 0.0193, I² = 88.5%, N = 124,501) and a lower risk of CVD incidence (pooled HR: 0.90, 95% CI: 0.82–0.98, p = 0.0173, I² = 87.2%, N = 323,854). Among the studies that used PDI, unhealthful plant-based diets were associated with increased risk of cardiovascular mortality (pooled HR: 1.05, 95% CI: 1.01–1.09, p = 0.0123, I² = 0.00%, N = 18,966), but not CVD incidence. Conversely, healthful plant-based diets were associated with decreased CVD incidence (pooled HR: 0.87, 95% CI: 0.80–0.95, p = 0.0011, I² = 57.5%, N = 71,301), but not mortality. Vegetarians also had significantly lower CVD incidence (HR: 0.81, 95% CI: 0.72–0.91, p = 0.0004, I² = 22.2%, N = 16,254), but similar CVD mortality or stroke risk when compared to the meat-eaters.

Conclusion: To date, this comprehensive study examines the effects of a plant-based diet on major clinical endpoints using more holistic PDIs. These findings highlight the favorable role of healthful plant-based foods in reducing cardiovascular mortality and CVD.

An Epidemiological Meta-Analysis on the Worldwide Prevalence, Resistance, and Outcomes of Spontaneous Bacterial Peritonitis in Cirrhosis

Background and Aims: Spontaneous bacterial peritonitis (SBP) is a common and potentially fatal complication of liver cirrhosis. This study aims to analyze the prevalence of SBP among liver cirrhotic patients according to geographical location and income level, and risk factors and outcomes of SBP. Methods: A systematic search for articles describing prevalence, risk factors and outcomes of SBP was conducted. A single-arm meta-analysis was performed using generalized linear mix model (GLMM) with Clopper-Pearson intervals. Results: Ninety-Nine articles, comprising a total of 5,861,142 individuals with cirrhosis were included. Pooled prevalence of SBP was found to be 17.12% globally (CI: 13.63-21.30%), highest in Africa (68.20%; CI: 12.17-97.08%), and lowest in North America (10.81%; CI: 5.32-20.73%). Prevalence of community-acquired SBP was 6.05% (CI: 4.32-8.40%), and 11.11% (CI: 5.84-20.11%,) for healthcare-associated SBP. Antibiotic-resistant microorganisms were found in 11.77% (CI: 7.63-17.73%) of SBP patients. Of which, methicillin-resistant Staphylococcus aureus was most common (6.23%; CI: 3.83-9.97%), followed by extended-spectrum beta-lactamase producing organisms (6.19%; CI: 3.32-11.26%), and lastly vancomycin-resistant enterococci (1.91%; CI: 0.41-8.46%). Subgroup analysis comparing prevalence, antibiotic resistance, and outcomes between income groups was conducted to explore a link between socioeconomic status and SBP, which revealed decreased risk of SBP and negative outcomes in high-income countries. Conclusion: SBP remains a frequent complication of liver cirrhosis worldwide. The drawn link between income level and SBP in liver cirrhosis may enable further insight on actions necessary to tackle the disease on a global scale.

A Meta-Analysis on the Incidence of Donor Related Depression after Liver Transplant

AIM

Living donor liver transplantation (LDLT) is increasing, yet gaps exist in the understanding of psychological wellbeing of donors after liver transplant. This meta-analysis seeks to evaluate the incidence and risk factors for donor-related depression after liver transplantation.

METHODS

A search was conducted on Medline and Embase database. Articles assessing incidence of depression in LDLT donors were included. Incidence was pooled after Freeman-Tukey double-arcsine transformation. For risk factors, dichotomous variables were analyzed with generalized linear model while a conventional meta regression with logit transformation was conducted for continuous variables.

RESULTS

Of 1,069 abstracts, 40 articles underwent full-text review. 17 articles were included. The pooled incidence of depression among 1,888 LT donors was 7.66% (CI: 4.47% - 12.80%). Depression rates were significantly higher in Asian compared to Western studies (RR: 1.73, CI: 1.19 - 2.52, p=0.0039). Female gender (p<0.001), Caucasian ethnicity (p=0.047), employment status (p<0.001) and lower education levels (p=0.044) were significantly associated with depression. Donor relationship with recipients was not a significant risk factor.

CONCLUSIONS

LDLT remains a core aspect of the treatment of end-stage liver disease. However, the high depression rates after LT suggest that there remains room for improvement in the care of donors' mental health post-transplant.

Is Fatty Liver Associated With Depression? A Meta-Analysis and Systematic Review on the Prevalence, Risk Factors, and Outcomes of Depression and Non-alcoholic Fatty Liver Disease

Background and Aims: Both non-alcoholic fatty liver disease (NAFLD) and depression have a high global prevalence which is projected to increase further. While studies exploring the association have been done, there are conflicting data. This study aims to assess the prevalence and association between depression and NAFLD.

Methods: Medline and Embase were searched from inception to March 3, 2020. Meta-analysis of proportions using the generalized linear mix model was conducted to analyze the pooled prevalence of depression in NAFLD patients. Risk factors for depression in NAFLD patients were evaluated in conventional pairwise meta-analysis.

Results: Ten studies involving 2,041,752 NAFLD patients were included. Pooled prevalence of depression was 18.21% (CI: 11.12–28.38%) in patients with NAFLD and 40.68% (CI: 25.11–58.37%) in patients with non-alcoholic steatohepatitis (NASH). NAFLD resulted in significantly higher risk of development of depression (OR: 1.29, CI: 1.02–1.64, p = 0.03). NASH patients had a significantly higher risk of depression compared with NAFLD patients (RR: 2.83, CI: 2.41–3.32, p < 0.001). Diabetes, body mass index (BMI), female sex, smoking, and history of pulmonary disease were significant risk factors for depression in NAFLD patients.

Conclusion: This study demonstrated a high prevalence of depression in NAFLD patients and a significant association between both conditions. Furthermore, patients with NASH had a significantly higher risk of depression compared with those with NAFLD. Diabetes, BMI, history of lung disease or smoking, and female gender were significant risk factors. Further studies investigating the pathophysiological mechanism underlying depression and NAFLD are needed.