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Dive into the research topics where Leon A. Adams is active.

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Featured researches published by Leon A. Adams.


Gastroenterology | 2015

Liver Fibrosis, but No Other Histologic Features, Is Associated With Long-term Outcomes of Patients With Nonalcoholic Fatty Liver Disease.

Paul Angulo; David E. Kleiner; Sanne Dam-Larsen; Leon A. Adams; Einar S. Björnsson; Phunchai Charatcharoenwitthaya; Peter R. Mills; Heather D. Lafferty; Alisha Stahler; Svanhildur Haflidadottir; Flemming Bendtsen

BACKGROUND & AIMS Histologic analysis of liver biopsy specimens allows for grading and staging of nonalcoholic fatty liver disease (NAFLD). We performed a longitudinal study to investigate the long-term prognostic relevance of histologic features for patients with NAFLD. METHODS We performed a retrospective analysis of 619 patients diagnosed with NAFLD from 1975 through 2005 at medical centers in the United States, Europe, and Thailand. Patients underwent laboratory and biopsy analyses, and were examined every 3-12 months after their diagnosis. Outcomes analyzed were overall mortality, liver transplantation, and liver-related events. Cumulative outcomes were compared by log-rank analysis. Cox proportional-hazards regression was used to estimate adjusted hazard ratios (HRs). Time at risk was determined from the date of liver biopsy to the date of outcome or last follow-up examination. RESULTS Over a median follow-up period of 12.6 years (range, 0.3-35.1 y), 193 of the patients (33.2%) died or underwent liver transplantation. Features of liver biopsies significantly associated with death or liver transplantation included fibrosis stage 1 (HR, 1.88; 95% confidence interval [CI], 1.28-2.77), stage 2 (HR, 2.89; 95% CI, 1.93-4.33), stage 3 (HR, 3.76; 95% CI, 2.40-5.89), and stage 4 (HR, 10.9; 95% CI, 6.06-19.62) compared with stage 0, as well as age (HR, 1.07; 95% CI, 1.05-1.08), diabetes (HR, 1.61; 95% CI, 1.13-2.30), current smoking (HR, 2.62; 95% CI, 1.67-4.10), and statin use (HR, 0.32; 95% CI, 0.14-0.70). Twenty-six patients (4.2%) developed liver-related events; fibrosis stage 3 (HR, 14.2; 95% CI, 3.38-59.68) and stage 4 (HR, 51.5; 95% CI, 9.87-269.2) compared with stage 0, were associated significantly with the events. Patients with fibrosis, regardless of steatohepatitis or NAFLD activity score, had shorter survival times than patients without fibrosis. CONCLUSIONS In a longitudinal study of patients with NAFLD, fibrosis stage, but no other histologic features of steatohepatitis, were associated independently with long-term overall mortality, liver transplantation, and liver-related events.


Canadian Medical Association Journal | 2005

Nonalcoholic fatty liver disease

Leon A. Adams; Paul Angulo; Keith D. Lindor

NONALCOHOLIC FATTY LIVER DISEASE is emerging as the most common chronic liver condition in the Western world. It is associated with insulin resistance and frequently occurs with features of the metabolic syndrome. Disease presentation ranges from asymptomatic elevated liver enzyme levels to cirrhosis with complications of liver failure and hepatocellular carcinoma. Current treatment recommendations are limited to weight loss and exercise, although several promising medications are on the horizon. In this article we discuss the etiology, pathogenesis and diagnosis of nonalcoholic fatty liver disease as well as approaches to its management.


The American Journal of Gastroenterology | 2009

NAFLD as a risk factor for the development of diabetes and the metabolic syndrome: an eleven-year follow-up study.

Leon A. Adams; Oliver R Waters; Matthew Knuiman; Robert R Elliott; John K. Olynyk

OBJECTIVES:Non-alcoholic fatty liver disease (NAFLD) uncommonly results in cirrhosis and liver-related death; however, its impact on the development of metabolic complications remains unclear. We sought to determine whether NAFLD with elevated aminotransaminase (ALT) levels was a risk factor for incident diabetes or the metabolic syndrome (MS) over an 11-year period.METHODS:Adult residents of Busselton, Western Australia underwent assessment in 1994–1995 as part of the Busselton Health Survey. NAFLD was diagnosed on the basis of a raised ALT (>40 IU/l) after the exclusion of alcohol, viral, metabolic, and autoimmune liver disease. NAFLD and non-NAFLD subjects were reassessed in 2005 for liver complications, diabetes, and the MS.RESULTS:A total of 358 subjects, 68% male (109 NAFLD, 249 non-NAFLD), mean age (s.d.) 59.9 (11.6) years, attended follow-up 11.1 years after the initial assessment. After excluding subjects with diabetes at baseline, those with NAFLD were more likely to have developed diabetes on follow-up (20/106, 18.9% vs. 15/246, 6.1%; P<0.001). After excluding subjects with MS at baseline, those with NAFLD were more likely to have developed MS at follow-up (27/81, 33.3% vs. 51/226, 22.6%; P=0.056). However, in multivariate logistic regression models, NAFLD was no longer a significant independent predictor of the development of diabetes or MS after adjusting for baseline waist circumference, hypertension, and insulin resistance. None of the subjects developed liver complications.CONCLUSIONS:Subjects with NAFLD and elevated ALT levels are at an increased risk of developing diabetes and the MS. This may be because of the presence of associated metabolic risk factors.


Clinical Chemistry | 2003

Validation of the FibroTest Biochemical Markers Score in Assessing Liver Fibrosis in Hepatitis C Patients

Enrico Rossi; Leon A. Adams; Alexander Prins; Max Bulsara; Bastiaan de Boer; George Garas; Gerry MacQuillan; David J. Speers; Gary P. Jeffrey

BACKGROUND Determining the stage of fibrosis by liver biopsy is important in managing patients with hepatitis C virus infection. We investigated the predictive value of the proprietary FibroTest score to accurately identify significant fibrosis in Australian hepatitis C patients. METHODS Serum obtained from 125 confirmed hepatitis C patients before antiviral therapy was analyzed for haptoglobin, alpha(2)-macroglobulin, apolipoprotein A1, bilirubin, and gamma-glutamyltransferase activity, and the FibroTest score was computed. Liver fibrosis pathology was staged according to a defined system on a scale of F0 to F4. We used predictive values and a ROC curve to assess the accuracy of FibroTest scores. RESULTS The prevalence of significant fibrosis defined by liver biopsy was 0.38. The most useful single test for predicting significant fibrosis was serum alpha(2)-macroglobulin (cutoff value, 2.52 g/L; sensitivity, 75%; specificity, 67%). The negative predictive value of a FibroTest score <0.1 was 85%, and the positive predictive value of a score >0.6 was 78%. Although 33 of the 125 patients had FibroTest scores <0.1 and were therefore deemed unlikely to have fibrosis, 6 (18%) had significant fibrosis. Conversely, of the 24 patients with scores >0.6 who were likely to have significant fibrosis, 5 (21%) had mild fibrosis. Of the 125 patients in the cohort, 57 (46%) could have avoided liver biopsy, but discrepant results were recorded in 11 of those 57 (19%). CONCLUSION The FibroTest score could not accurately predict the presence or absence of significant liver fibrosis.


Postgraduate Medical Journal | 2006

Treatment of non-alcoholic fatty liver disease.

Leon A. Adams; Paul Angulo

Non-alcoholic fatty liver disease (NAFLD) is common and may progress to cirrhosis and its complications. The pathogenesis of steatosis and cellular injury is thought to be related mostly to insulin resistance and oxidative stress. Therefore, management entails identification and treatment of metabolic risk factors, improving insulin sensitivity, and increasing antioxidant defences in the liver. Weight loss and exercise improve insulin sensitivity. Bariatric surgery may improve liver histology in patients with morbid obesity. Insulin sensitising drugs showed promise in pilot trials as have a number of hepatoprotective agents. Further randomised, well controlled trials are required to determine the efficacy of these drugs.


Hepatology | 2014

Extrahepatic complications of nonalcoholic fatty liver disease

Matthew J. Armstrong; Leon A. Adams; Ali Canbay; Wing-Kin Syn

Nonalcoholic fatty liver disease (NAFLD) is a leading cause of chronic liver disease, and is strongly associated with the metabolic syndrome. In the last decade, it has become apparent that the clinical burden of NAFLD is not restricted to liver‐related morbidity or mortality, and the majority of deaths in NAFLD patients are related to cardiovascular disease (CVD) and cancer. These findings have fuelled concerns that NAFLD may be a new, and added risk factor for extrahepatic diseases such as CVD, chronic kidney disease (CKD), colorectal cancer, endocrinopathies (including type 2 diabetes mellitus [T2DM] and thyroid dysfunction), and osteoporosis. In this review we critically appraise key studies on NAFLD‐associated extrahepatic disease. There was marked heterogeneity between studies in study design (cross‐sectional versus prospective; sample size; presence/absence of well‐defined controls), population (ethnic diversity; community‐based versus hospital‐based cohorts), and method of NAFLD diagnosis (liver enzymes versus imaging versus biopsy). Taking this into account, the cumulative evidence to date suggests that individuals with NAFLD (specifically, nonalcoholic steatohepatitis) harbor an increased and independent risk of developing CVD, T2DM, CKD, and colorectal neoplasms. We propose future studies are necessary to better understand these risks, and suggest an example of a screening strategy. (Hepatology 2014;59:1174–1197)


Nature Reviews Endocrinology | 2011

Nonalcoholic fatty liver disease and diabetes mellitus: pathogenesis and treatment.

Briohny W. Smith; Leon A. Adams

Nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM) frequently coexist as they share the pathogenic abnormalities of excess adiposity and insulin resistance. Although type 1 diabetes mellitus (T1DM) is due to a relative lack of insulin, an increased prevalence of obesity and insulin resistance in this population means that NAFLD also commonly coexists with this condition. Both T2DM and NAFLD are associated with adverse outcomes of the other; T2DM is a risk factor for progressive liver disease and liver-related death in patients with NAFLD, whereas NAFLD may be a marker of cardiovascular risk and mortality in individuals with T2DM. Nonalcoholic steatohepatitis—a histological subtype of NAFLD characterized by hepatocyte injury and inflammation—is present in approximately 10% of patients with T2DM and is associated with an increased risk for the development of cirrhosis and liver-related death. Current treatment strategies aim to improve insulin resistance via weight loss and exercise, improve insulin sensitivity by the use of insulin-sensitizing agents (for example, pioglitazone) and reduce oxidative stress by the use of antioxidants, such as vitamin E. Pioglitazone and vitamin E supplementation show the most promise in improving hepatic steatosis and inflammation but have not yet been demonstrated to improve fibrosis, and concern remains regarding the toxicity of long-term use of both of these agents.


Critical Reviews in Clinical Laboratory Sciences | 2011

Non-alcoholic fatty liver disease

Briohny W. Smith; Leon A. Adams

Non-alcoholic fatty liver disease (NAFLD) refers to the accumulation of hepatic steatosis not due to excess alcohol consumption. The prevalence of NAFLD is up to 30% in developed countries and nearly 10% in developing nations, making NAFLD the most common liver condition in the world. The pathogenesis of NAFLD is related to insulin resistance and, thus, it is frequently found in individuals who have central obesity or diabetes. Insulin resistance and excess adiposity are associated with increased lipid influx into the liver and increased de novo hepatic lipogenesis, promoting hepatic triglyceride accumulation. Defects in lipid utilization via mitochondrial oxidation and lipid export may also contribute to hepatic lipid build-up. Adipocytokine alterations, lipotoxicity from saturated fatty acids and fructose have been all been implicated in causing hepatocyte injury in NAFLD through pathways involving oxidative and endoplasmic reticulum stress. Clinically, NAFLD is commonly asymptomatic and frequently detected incidentally by blood liver function tests or imaging performed for other reasons. Subjects with NAFLD have a higher mortality rate than the general population and are at increased risk of developing cardiovascular disease and diabetes in the future. Histologically, NAFLD occurs as a spectrum from mild hepatic steatosis only, to non-alcoholic steatohepatitis (NASH) characterized by hepatocellular injury and inflammation, to cirrhosis. A diagnosis of NASH with associated fibrosis heralds a more significant prognosis as it is more likely to progressive to cirrhosis with complications of hepatic failure and hepatocellular carcinoma. Currently, the diagnosis of NASH requires a liver biopsy, however, serum based markers of hepatocyte apoptosis such as cytokeratin-18 fragments offer promise as accurate non-invasive diagnostic tests. Treatment of NAFLD revolves around addressing concomitant metabolic risk factors and improving insulin resistance through weight loss measures and exercise. Insulin sensitizing agents such as pioglitazone and anti-oxidant agents such as vitamin E show some promise in improving liver histology in patients with NASH, however, the long-term benefit of these medications has not been demonstrated.


The American Journal of Gastroenterology | 2010

Nonalcoholic fatty liver disease increases risk of death among patients with diabetes: a community-based cohort study.

Leon A. Adams; Jennifer L. St. Sauver; Phunchai Charatcharoenwitthaya; Felicity Enders; Terry M. Therneau; Paul Angulo

OBJECTIVES:The significance of nonalcoholic fatty liver disease (NAFLD) among patients with diabetes is unknown. We sought to determine whether a diagnosis of NAFLD influenced mortality among a community-based cohort of patients with type II diabetes mellitus.METHODS:A total of 337 residents of Olmsted County, Minnesota with diabetes mellitus diagnosed between 1980 and 2000 were identified using the Rochester Epidemiology Project and the Mayo Laboratory Information System, and followed for 10.9±5.2 years (range 0.1–25). Survival was analyzed using Cox proportional hazards modeling, with NAFLD treated as a time-dependent covariate.RESULTS:Among the 337 residents, 116 were diagnosed with NAFLD 0.9±4.6 years after diabetes diagnosis. Patients with NAFLD were younger, and more likely to be female and obese. Overall, 99/337 (29%) patients died. In multivariate analysis to adjust for confounders, overall mortality was significantly associated with a diagnosis of NAFLD (hazard ratio (HR) 2.2; 95% confidence interval (CI) 1.1, 4.2; P=0.03), presence of ischemic heart disease (HR 2.3; 95% CI 1.2, 4.4), and duration of diabetes (HR per 1 year, 1.1; 95% CI 1.03, 1.2). The most common causes of death in the NAFLD cohort were malignancy (33% of deaths), liver-related complications (19% of deaths), and ischemic heart disease (19% of deaths). In adjusted multivariate models, NAFLD was borderline associated with an increased risk of dying from malignancy (HR 2.3; 95% CI 0.9, 5.9; P=0.09) and not from cardiovascular disease (HR 0.9; 95% CI 0.3, 2.4; P=0.81).CONCLUSIONS:The diagnosis of NAFLD is associated with an increased risk of overall death among patients with diabetes mellitus.


Liver Transplantation | 2008

Bevacizumab reverses need for liver transplantation in hereditary hemorrhagic telangiectasia

Andrew Mitchell; Leon A. Adams; Gerry MacQuillan; Jon Tibballs; Rohan vanden Driesen; Luc Delriviere

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disease characterized by mucocutaneous and visceral telangiectasia. Hepatic involvement with vascular malformations may lead to portal hypertension, biliary ischemia, and high‐output cardiac failure. Liver transplantation is indicated for life‐threatening disease but carries significant risk from surgery and chronic immunosuppression. We report a case of a 47‐year‐old woman with HHT successfully treated with the vascular endothelial growth factor (VEGF) antibody bevacizumab. The patient was referred for consideration of liver transplantation because of hepatic HHT leading to high‐output cardiac failure, diuretic resistant ascites, cholestasis, and malnutrition. As she was considered a high‐risk candidate for transplantation, she underwent 6 courses of bevacizumab (5 mg/kg) over 12 weeks. A dramatic improvement in her clinical state was observed after 3 months with reversal of cholestasis, resolution of cardiac failure and ascites, and improvement in nutritional status with a 10% dry weight increase. Treatment induced a marked reduction in liver vascularity and halving of her liver volume from 4807 to 2269 mL over 6 months. This was associated with normalization of her cardiac output from 10.2 to 5.1 L/minute. Correspondingly, she ceased diuretic medications, returned to full‐time work, and was delisted as a transplant candidate. She remains well 6 months after completing treatment. In conclusion, antagonism of VEGF receptors led to a dramatic regression of hepatic vascular malformations and reversal of high‐output cardiac failure and complications of portal hypertension in this patient with HHT. Bevacizumab may potentially alleviate the need for liver transplantation in this group of patients. Liver Transpl 14:210–213. 2008.

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Gary P. Jeffrey

Sir Charles Gairdner Hospital

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Gerry MacQuillan

Sir Charles Gairdner Hospital

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George Garas

Sir Charles Gairdner Hospital

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Trevor A. Mori

University of Western Australia

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Lawrence J. Beilin

University of Western Australia

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Oyekoya T. Ayonrinde

University of Western Australia

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Yi Huang

University of Western Australia

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Paul Angulo

University of Kentucky

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