Project description:Data on prevalence and profile of nonalcoholic fatty liver disease (NAFLD) among individuals who are lean (normal body mass index) is unclear. Published data from studies comparing lean with obese NAFLD or with healthy subjects on prevalence, comorbidities, liver chemistry and histology, and metabolic/inflammatory markers were analyzed. Data were reported as odds ratio and 95% confidence interval for categorical variables and difference of means for continuous variables. Analysis of 53 studies on 65,029 subjects with NAFLD (38,084 lean) and 249,544 healthy subjects showed a prevalence of lean NAFLD at 11.2% in the general population. Among individuals with NAFLD, the prevalence of lean NAFLD was 25.3%. Lean NAFLD versus healthy subjects had higher odds for abnormalities on metabolic profile, including metabolic syndrome and its components, renal and liver function, and patatin-like phospholipase domain-containing protein 3 (PNPLA3) G allele; and inflammatory profile, including uric acid and C-reactive protein. The abnormalities were less severe among lean versus obese NAFLD on metabolic syndrome with its components, renal and liver chemistry, liver stiffness measurement, PNPLA3 and transmembrane 6 superfamily member 2 polymorphisms, and uric acid levels as markers of inflammation. Lean NAFLD had less severe histologic findings, including hepatocyte ballooning, lobular inflammation, NAFLD activity score, and fibrosis stage. Limited data also showed worse outcomes between obese versus lean NAFLD. Conclusion: Lean NAFLD is a distinct entity with metabolic, biochemical, and inflammatory abnormalities compared to healthy subjects and a more favorable profile, including liver histology of steatohepatitis and fibrosis stage, compared to obese NAFLD. We suggest that prospective multicenter studies examine long-term hepatic and extrahepatic outcomes in individuals with lean NAFLD.
Project description:BackgroundNonalcoholic fatty liver disease (NAFLD) is a significant public health burden, with up to 30% of the US population affected. The prevalence of NAFLD among inflammatory bowel disease (IBD) patients is unknown. Understanding risk factors for NAFLD in IBD patients has implications in the treatment of these patients. The purpose of this study was to determine the prevalence of NAFLD among IBD patients and to identify risk factors associated with NAFLD development.MethodsEmbase and MEDLINE databases were searched using Medical Subject Headlines to find studies that assessed the prevalence of NAFLD among IBD patients. Twenty-seven English-language research abstracts/articles were identified between January 2005 and April 2018. Meta-analyses were performed using random-effects models. Prevalence of NAFLD among IBD patients was compared with prevalence of NAFLD in the general population.ResultsBased on data pooled from all 27 studies, the prevalence of NAFLD among IBD patients was 32% (95% CI, 24%-40%) with substantial heterogeneity (I2 = 98%). The prevalence of NAFLD among IBD patients (32%) is statistically significantly higher than the prevalence of NAFLD in the general population (25.2%; P < 0.001). Factors associated with the development of NAFLD among IBD patients included age, BMI, diabetes, IBD duration, and prior history of bowel resection.ConclusionsThere is a higher prevalence of NAFLD among IBD patients compared with the general population. Previous treatment regimens may be a risk factor for the development of NAFLD. Future studies are needed to further clarify these risk factors and determine screening recommendations.
Project description:BackgroundNonalcoholic fatty liver disease (NAFLD) is one of the common causes of chronic liver disease globally. Obesity, metabolic diseases, and exposure to some environmental agents contribute to NAFLD. NAFLD is commonly considered a precursor for some types of cancers. Since the leading causes of death in people with NAFLD are cardiovascular disease and extrahepatic cancers, it is important to understand the mechanisms of the progression of NAFLD to control its progression and identify its association with extrahepatic cancers. Thus, this review aims to estimate the global prevalence of NAFLD in association with the risk of extrahepatic cancers.ObjectiveWe aimed to determine the prevalence of various cancers in NAFLD patients and the association between NAFLD and cancer.MethodsWe searched PubMed, ProQuest, Scopus, and Web of Science from database inception to March 2022 to identify eligible studies reporting the prevalence of NAFLD and the risk of incident cancers among adult individuals (aged ≥18 years). Data from selected studies were extracted, and meta-analysis was performed using random effects models to obtain the pooled prevalence with the 95% CI. The quality of the evidence was assessed with the Newcastle-Ottawa Scale.ResultsWe identified 11 studies that met our inclusion criteria, involving 222,523 adults and 3 types of cancer: hepatocellular carcinoma (HCC), breast cancer, and other types of extrahepatic cancer. The overall pooled prevalence of NAFLD and cancer was 26% (95% CI 16%-35%), while 25% of people had NAFLD and HCC (95% CI 7%-42%). NAFLD and breast cancer had the highest prevalence out of the 3 forms of cancer at 30% (95% CI 14%-45%), while the pooled prevalence for NAFLD and other cancers was 21% (95% CI 12%-31%).ConclusionsThe review suggests that people with NAFLD may be at an increased risk of cancer that might not affect not only the liver but also other organs, such as the breast and bile duct. The findings serve as important evidence for policymakers to evaluate and recommend measures to reduce the prevalence of NAFLD through lifestyle and environmental preventive approaches.Trial registrationPROSPERO CRD42022321946; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=321946.
Project description:BackgroundOwing to long-term antiretroviral therapy (ART), the incidence of non-HIV-related chronic diseases is increasing, and liver disease is the leading cause of increased AIDS mortality. Moreover, the prevalence of NAFLD and liver fibrosis has been reported to vary widely across regions and studies. There is no precise description of the trend and characteristics of NAFLD in PLWH. Here, we aimed to explore the prevalence and outcomes of NAFLD in people living with HIV (PLWH).MethodsThe PubMed, Web of Science, Embase, and Cochrane Library databases were searched on August 15, 2023, for studies that evaluated the prevalence of NAFLD or liver fibrosis among PLWH. The meta-synthesized effects of NAFLD and liver fibrosis were the primary outcomes, and potential moderators were the secondary outcomes. The meta-analysis of the combined event rate (ER) and random effects was conducted on the basis of the number of individuals with NAFLD, the number of individuals with liver fibrosis, and the total sample size.ResultsOf the 3520 studies identified, 41 studies were eligible for the meta-analysis. The results revealed that the combined ERs of NAFLD and liver fibrosis were 0.38 (95% CI: 0.33-0.43, p < 0.01) and 0.25 (95% CI: 0.18-0.32, p < 0.01), respectively.ConclusionsThis meta-analysis provided empirical evidence that the prevalence of NAFLD and liver fibrosis in PLWH is greater than that in the general population, which requires sufficient attention. In the HIV population, noninvasive imaging to monitor NAFLD changes should be strengthened, and a high TG level might be an early predictive indicator for HIV-associated fatty liver disease; however, large-scale prospective clinical research data are still needed for further validation and evaluation.
Project description:BACKGROUND & AIMS:Previous studies examining the relationship between the C282Y and H63D HFE mutations and presence of nonalcoholic fatty liver disease (NAFLD) have yielded conflicting results. The goal of this study was to systematically evaluate and summarize data on the association between these two variants and the presence of NAFLD. METHODS:The authors searched EMBASE and PUBMED from August 1, 1996 to August 12, 2010. Two investigators independently conducted data abstraction. Ethnic specific weighted prevalence was calculated and pooled odds ratios were estimated using the random effects model. RESULTS:From 2542 references, the authors included 16 case-control studies and 14 case-only studies, or 2610 cases and 7298 controls. The majority of the studies came from Caucasian populations (2287 cases and 4275 controls). The weighted prevalence of HFE mutations in cases was comparable to controls. The meta-analysis was restricted to Caucasians only because of the small sample size of non Caucasian participants. The pooled odds ratio for the presence of any HFE genetic variant in cases was 1.03 (95%CI: 0.90, 1.17; I(2): 65.8%, 95%CI: 38.5, 81.0). The presence of other genotypes and secondary analyses yielded similar non significant findings. CONCLUSIONS:Our systematic review does not support an association between the HFE genetic variants and the presence of NAFLD.
Project description:Individuals with nonalcoholic fatty liver disease (NAFLD) are characterized by increased cardiovascular risk. Endothelial dysfunction, a mechanism implicated in those processes, may constitute the missing link in this interaction. Therefore, this systematic review and meta-analysis aims to evaluate the association of endothelial dysfunction, assessed by flow-mediated dilation (FMD) of the brachial artery, with NAFLD. We conducted a systematic literature search for studies assessing the difference in FMD between patients with NAFLD and controls. Exclusion criteria consisted of preclinical studies, studies in children/adolescents, no FMD assessment, and the absence of an NAFLD/control group. The database search identified 96 studies. Following the application of the exclusion criteria, 22 studies were included in the meta-analysis (NAFLD: 2164 subjects; control: 3322 subjects). Compared with controls, patients with NAFLD had significantly lower FMD% values (SMD: -1.37, 95% CI -1.91 to -0.83, p < 0.001, I2: 98%). Results remained unaffected after exclusion of any single study. Subgroup analysis revealed significantly decreased FMD in NAFLD subjects diagnosed with liver ultrasound or liver biopsy compared with method combination or other methods, while no differences were observed according to the chosen cuff inflation threshold, the presence of a significant difference in obesity measures between the groups, or the type of the control group (age- and sex-matched vs. other). Funnel plot asymmetry was not observed. Finally, compared with patients with pure steatosis, individuals with nonalcoholic steatohepatitis had significantly lower FMD (SMD: -0.81, 95% CI -1.51 to -0.31, p = 0.003, I2: 81%). In conclusion, FMD of the brachial artery, indicative of endothelial dysfunction, was significantly reduced in subjects with nonalcoholic fatty liver disease. Patients with nonalcoholic steatohepatitis might be facing a more pronounced endothelial impairment.
Project description:AimAssociations between antinuclear antibodies (ANAs) and disease severity in nonalcoholic fatty liver disease (NAFLD) remain unclear. This study aimed to provide reliable estimates of ANA prevalence in subjects with biopsy-proven NAFLD and to investigate whether its associations with liver disease severity were established.MethodsObservational studies measuring ANA in NAFLD patients were derived from the PubMed, Embase, and Web of Science databases from inception to March 30, 2022. The effect size was presented as the pooled risk difference, unstandardized mean differences (MDs), and odds ratio (OR) with a 95% confidence interval (CI).ResultsThirteen articles involving 2331 patients were finally included. Among the subjects with biopsy-proven NAFLD, the overall prevalence of ANA positivity was high as 23% (95% CI: 19%-28%), but there were no statistically significant differences between ANA-positive and ANA-negative NAFLD patients in the levels of liver enzymes and blood lipids, grades of hepatocellular ballooning, lobular and portal inflammation, or risks of moderate-severe steatosis and significant fibrosis. However, the subgroup analysis showed that different geographic regions led to diverse results. ANA positivity was associated with a significantly elevated risk of significant fibrosis in the Eastern population (OR = 2.30, 95% CI: 1.30-4.06) but not in the Western population (OR = 1.00, 95% CI: 0.54-1.83).ConclusionsSerum ANA was present in approximately one-quarter of subjects with biopsy-proven NAFLD, but it conferred a greater risk of significant fibrosis only in Eastern but not Western populations.
Project description:BackgroundThe gut-liver axis is considered to play a critical role in the development and progression of nonalcoholic fatty liver disease (NAFLD). The integrity of the epithelial barrier is crucial to protect the liver against the invasion of microbial products from the gut, although its exact role in NAFLD onset and progression is not clear.MethodsWe performed a systematic review and meta-analysis of studies that addressed the intestinal permeability (IP) in association with NAFLD presence or severity as defined by the presence of nonalcoholic steatohepatitis (NASH) and the degree of steatosis, hepatic inflammation or fibrosis. A total of 14 studies were eligible for inclusion.ResultsStudies investigating IP in adult (n = 6) and paediatric (n = 8) NAFLD showed similar results. Thirteen of the included studies focussed on small IP, two studies on whole gut permeability and none on colonic permeability. In the pooled analysis, NAFLD patients showed an increased small intestinal permeability compared to healthy controls based on dual sugar tests (standardized mean difference 0.79, 95% CI 0.49-1.08) and serum zonulin levels (standardized mean difference 1.04 ng/mL, 95% CI 0.40-1.68). No clear difference in IP was observed between simple steatosis and NASH patients. Furthermore, whole gut and small intestinal permeability increased with the degree of hepatic steatosis in 4/4 studies, while no association with hepatic inflammation or fibrosis was observed.ConclusionBased on the limited number of studies available, IP appears to be increased in NAFLD patients compared to healthy controls and is associated with the degree of hepatic steatosis.
Project description:AimThis sudy aims to investigate the association between insomnia or excessive daytime sleepiness (EDS) and risk of nonalcoholic fatty liver disease (NAFLD).MethodsWe searched published studies indexed in MEDLINE and EMBASE database from inception to December 2015. Studies that reported odds ratios (ORs), risk ratios, hazard ratios or standardized incidence ratio with 95% confidence intervals (CI) comparing the risk of NAFLD among participants who had insomnia or EDS versus those without insomnia or EDS were included. Pooled ORs and 95% CI were calculated using a random-effect, generic inverse variance method of DerSimonian and Laird. Cochran's Q test and I2 statistic were used to determine the between-study heterogeneity.ResultsOur search strategy yielded 2117 potentially relevant articles (781 articles from MEDLINE and 1336 articles from EMBASE). After comprehensive review, seven studies (three cross-sectional studies and four case-control studies) were found to be eligible and were included in the meta-analysis. The risk of NAFLD in participants who had insomnia was significantly higher with the pooled OR of 1.13 (95% CI, 1.00-1.27). The statistical heterogeneity was moderate with an I2 of 62%. Elevated risk of NAFLD was also observed among participants with EDS even though the 95% CI was wider and did not reach statistical significance (pooled OR 2.21; 95% CI, 0.84-5.82). The statistical heterogeneity was moderate with an I2 of 62%.ConclusionsOur study demonstrated an increased risk of NAFLD among participants who had insomnia or EDS. Whether this association is causal needs further investigations.
Project description:Background and aimsProbiotics was considered as a potential therapy for nonalcoholic fatty liver disease (NAFLD) without approval and comprehensive assessment in recent years, which call for a meta-analysis.MethodsWe performed electronic and manual searches including English and Chinese databases published before April 2019, with the use of mesh term and free text of "nonalcoholic fatty liver disease" and "probiotics." Clinical trials evaluating the efficacy of probiotic therapy in NAFLD patients were included according to the eligibility criteria. With the use of random effects models, clinical outcomes were presented as weighted mean difference (WMD) with 95% confidence interval (CI), while heterogeneity and meta-regression were also assessed.Results28 clinical trials enrolling 1555 criterion proven NAFLD patients with the use of probiotics from 4 to 28 weeks were included. Overall, probiotic therapy had beneficial effects on body mass index (WMD: -1.46, 95% CI: [-2.44, -0.48]), alanine aminotransferase (WMD: -13.40, 95% CI: [-17.03, -9.77]), aspartate transaminase (WMD: -13.54, 95% CI: [-17.86, -9.22]), gamma-glutamyl transpeptidase (WMD: -9.88, 95% CI: [-17.77, -1.99]), insulin (WMD: -1.32, 95% CI: [-2.43, -0.21]), homeostasis model assessment-insulin resistance (WMD: -0.42, 95% CI: [-0.73, -0.12]), and total cholesterol (WMD: -15.38, 95% CI: [-26.50, -4.25]), but not in fasting blood sugar, lipid profiles, or tumor necrosis factor-alpha.ConclusionThe systematic review and meta-analysis support that probiotics are superior to placebo in NAFLD patients and could be utilized as a common complementary therapeutic approach.