Angiotensin-receptor blockers as therapy for mild-to-moderate hypertension-associated non-alcoholic steatohepatitis

Impact of current treatments on liver disease, glucose metabolism and cardiovascular risk in non-alcoholic fatty liver disease (NAFLD): a systematic review and meta-analysis of randomised trials

AIMS/HYPOTHESIS

Non-alcoholic fatty liver disease (NAFLD) encompasses a spectrum ranging from simple steatosis to non-alcoholic steatohepatitis (NASH): NAFLD causes an increased risk of cardiovascular disease, diabetes and liver-related complications (the latter confined to NASH). The effect of proposed treatments on liver disease, glucose metabolism and cardiovascular risk in NAFLD is unknown. We reviewed the evidence for the management of liver disease and cardio-metabolic risk in NAFLD.

METHODS

Publications through November 2011 were systematically reviewed by two authors. Outcomes evaluated though standard methods were: histological/radiological/biochemical features of NAFLD, variables of glucose metabolism and cardiovascular risk factors. Seventy-eight randomised trials were included (38 in NASH, 40 in NAFLD): 41% assessed post-treatment histology, 71% assessed glucose metabolism and 88% assessed cardiovascular risk factors. Lifestyle intervention, thiazolidinediones, metformin and antioxidants were most extensively evaluated.

RESULTS

Lifestyle-induced weight loss was safe and improved cardio-metabolic risk profile; a weight loss ≥7% improved histological disease activity, but was achieved by <50% patients. Statins and polyunsaturated fatty acids improved steatosis, but their effects on liver histology are unknown. Thiazolidinediones improved histological disease activity, glucose, lipid and inflammatory variables and delayed fibrosis progression. Pioglitazone also improved blood pressure. Weight gain (up to 4.8%) was common. Antioxidants yielded mixed histological results: vitamin E improved histological disease activity when administered for 2 years, but increased insulin resistance and plasma triacylglycerols.

CONCLUSIONS/INTERPRETATION

Weight loss is safe, and improves liver histology and cardio-metabolic profile. For patients not responding to lifestyle intervention, pioglitazone improves histological disease activity, slows fibrosis progression and extensively ameliorates cardio-metabolic endpoints. Further randomised controlled trials (RCTs) of adequate size and duration will assess long-term safety and efficacy of proposed treatments on clinical outcomes.

Nonalcoholic fatty liver disease: a review of the spectrum of disease, diagnosis, and therapy

Worldwide, there is an epidemic of obesity and overweight, with two-thirds of Americans affected. A strong association exists between excessive body weight and nonalcoholic fatty liver disease (NAFLD), the most common etiology of abnormal liver function tests. Nonalcoholic fatty liver disease is a spectrum of liver disease, from a "bland" fatty infiltration to chronic hepatitis (nonalcoholic steatohepatitis or NASH), that can result in cirrhosis and organ failure. With the increasing prevalence of obesity in the world, the proportion of people affected by NAFLD is only expected to be parallel. Although primarily noted in obese individuals, NAFLD has also been associated with a number of surgical procedures, metabolic conditions, and medications. NASH is commonly underdiagnosed as most affected patients are symptom free, and routine screening is not performed. Noninvasive diagnostic testing is not sensitive in diagnosis or staging the severity of disease. Fatty infiltration and oxidative injury to the hepatocytes are believed to be the major factors behind the progression of disease from simple fatty infiltration of the liver to chronic hepatitis. Understanding the inflammatory pathways involved in NASH is a subject of extensive research. Currently, few proven treatment options exist, and controlled weight reduction is the only safe modality recommended for treatment of NASH.

Pathophysiology guided treatment of nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease is a spectrum that ranges from benign steatosis to steatohepatitis. It has become the most common cause of chronic liver disease, and yet there continues to be a lack of effective therapeutic options. This article reviews current concepts underlying the pathophysiological basis of nonalcoholic steatohepatitis from development of insulin resistance to the establishment of fibrosis. Then using a physiology-based approach, specific targeted therapeutics are reviewed along with their drawbacks. The evidence behind current therapies is based predominantly on small trials and, thus, no recommendations can be made until larger randomized trials are conducted.

Inflammation and fibrogenesis in steatohepatitis

Nonalcoholic fatty liver disease consists of a range of disorders characterized by excess accumulation of triglyceride within the liver. Whereas simple steatosis is clinically benign, nonalcoholic steatohepatitis (NASH) often progresses to cirrhosis. Inflammation and fibrogenesis are closely inter-related and are major targets of NASH research. Experimental data have shown that inflammation in NASH is caused by insulin resistance, systemic lipotoxicity due to overnutrition, lipid metabolites, the production of proinflammatory cytokines and adipokines by visceral adipose tissue, gut-derived bacteria, and oxidative stress. In NASH-associated fibrosis, the principal cell type responsible for extracellular matrix production is recognized as the hepatic stellate cell. Although the fibrotic mechanisms underlying NASH are largely similar to those observed in other chronic liver diseases, the altered patterns of circulating adipokines, the generation of oxidative stress, and the hormonal profile associated with the metabolic syndrome might play unique roles in the fibrogenesis associated with the disease. Information on the basic pathogenesis of NASH with a focus on the generation of inflammation and fibrosis will be discussed.

Impaired renal function in morbid obese patients with nonalcoholic fatty liver disease

INTRODUCTION AND AIMS

Obesity is a common risk factor for nonalcoholic fatty liver disease (NAFLD) and chronic kidney disease (CKD). NAFLD and CKD have been associated in many epidemiological studies. We hypothesize that more severe liver disease, namely nonalcoholic steatohepatitis (NASH), is related with further renal impairment. We aimed to evaluate if changes in renal function were present in morbid obese patients with NAFLD.

METHODS

Prospective and consecutive recruitment of morbid obese patients with biopsy proven NAFLD obtained during bariatric surgery. Renal function was evaluated with CKD-Epidemiology Collaboration estimated glomerular filtration rate (eGFR). Plasmatic adiponectin, leptin and active ghrelin concentrations were determined.

RESULTS

One hundred and forty-eight patients were included of whom 25% had NASH and 75% simple steatosis. NASH patients were older, with higher body mass index and had more frequently metabolic syndrome and lower eGFR (97 ± 22 vs 106 ± 16 ml/min/1.73(2), P = 0.035). NASH conferred an odds ratio (OR) 3.0 (1.3-7.0) for eGFR < 90 and OR 9.7 (1.0-96.4) for eGFR < 60 ml/min/1.73(2). eGFR < 90 ml/min/1.73(2) associated with aspartate aminotransferase [OR 2.9 (1.1-7.6)] and γ-glutamyl transpeptidase elevation [OR 3.0 (1.3-7.2)], NASH [OR 3.0 (1.3-7.0)], any lobular inflammatory activity [OR 3.0 (1.3-7.0)] and severe fibrosis [OR 3.4 (1.1-10.8)]. Neither eGFR nor liver histology was associated with adipokines levels.

CONCLUSIONS

In morbid obese patients, NASH, particularly lobular inflammation and advanced fibrosis, associates with mild decreases in eGFR, suggesting a common inflammatory link between liver and renal lesion.

Focus on therapeutic strategies of nonalcoholic Fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the Western world (it affects 30% of the general adult population). The NAFLD encompasses a histological spectrum ranging from simple steatosis to nonalcoholic steatohepatitis (NASH), defined by steatosis, hepatocellular damage, and lobular inflammation in individuals without significant alcohol consumption and negative viral, congenital, and autoimmune liver disease markers. Currently, NAFLD is considered an emerging epidemic in light of the dramatic increase in obesity rates. With the progressive nature of NASH and its rising prevalence there is a significant need for a specific and targeted treatments since to date there has not been any validated therapies for NAFLD other than weight loss, which is well known to have a poor long-term success rate. In recent years, visceral adipose tissue has taken an important role in NAFLD pathogenesis, and current therapeutic approaches aim at reducing visceral obesity and free fatty acid overflow to the liver. This paper is focused on the treatments used for NAFLD and the potential new therapy.

Evolutionary cost analysis of valsartan initiation among patients with hypertension: a time series approach

OBJECTIVES

This study examines the evolutionary impact of valsartan initiation on medical costs.

METHODS

A retrospective time series study design was used with a large, US national commercial claims database for the period of 2004-2008. Hypertensive patients who initiated valsartan between the ages of 18 and 63, and had continuous enrollment for 24-month pre-initiation period and 24-month post-initiation period were selected. Patients' monthly medical costs were calculated based on individual claims. A novel time series model was devised with monthly medical costs as its dependent variables, autoregressive integrated moving average (ARIMA) as its stochastic components, and four indicative variables as its decomposed interventional components. The number of post-initiation months before a cost-offset point was also assessed.

RESULTS

Patients (n = 18,269) had mean age of 53 at the initiation date, and 53% of them were female. The most common co-morbid conditions were dyslipidemia (52%), diabetes (24%), and hypertensive complications (17%). The time series model suggests that medical costs were increasing by approximately $10 per month (p < 0.01) before the initiation, and decreasing by approximately $6 per month (p < 0.01) after the initiation. After the 4th post-initiation month, medical costs for patients with the initiation were statistically significantly lower (p < 0.01) than forecasted medical costs for the same patients without the initiation.

LIMITATIONS

The study has its limitations in data representativeness, ability to collect unrecorded clinical conditions, treatments, and costs, as well as its generalizability to patients with different characteristics.

CONCLUSIONS

Commercially insured hypertensive patients experienced monthly medical cost increase before valsartan initiation. Based on our model, the evolutionary impact of the initiation on medical costs included a temporary cost surge, a gradual, consistent, and statistically significant cost decrease, and a cost-offset point around the 4th post-initiation month.

Non-alcoholic fatty liver disease

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.

Nonalcoholic steatohepatitis: the therapeutic challenge of a global epidemic

PURPOSE OF REVIEW

Nonalcoholic fatty liver (NAFL) and especially its inflammatory variant nonalcoholic steatohepatitis (NASH) have become a major challenge to healthcare systems worldwide because of the increasing prevalence of its major risk factors obesity and type 2 diabetes, which are closely linked to overeating, physical inactivity, and the metabolic syndrome.

RECENT FINDINGS

Between 10 and 20% of patients with NAFL develop NASH, which can progress to cirrhosis, end-stage liver disease, and hepatocellular carcinoma. The overall mortality in these patients is significantly increased because of both cardiovascular and liver-related complications. Sustained weight loss by diet and exercise, which is the most effective therapeutic measure, is only achieved by a minority of patients, having led to a great yet unmet need for medical therapies of NASH.

SUMMARY

Pharmacological therapies should target the underlying pathophysiology that involves insulin resistance, enhanced peripheral lipolysis and release of free fatty acids, oxidative stress, accumulation of toxic lipids, adipose tissue inflammation, sensitization of hepatocytes toward apoptotic cell death, and fibrogenesis. However, pharmacological therapy that is well tolerated, cost-effective, and poses an acceptable risk-to-benefit ratio has still to be identified. This review summarizes the current and promising treatment options and their implications for future research and clinical practice.

Mechanisms linking nonalcoholic fatty liver disease with coronary artery disease

The most common cause of death in patients with nonalcoholic fatty liver disease (NAFLD) is coronary artery disease (CAD), not chronic liver disease. Fatty liver increases cardiovascular risk by classical (dyslipidemia, hypertension, diabetes) and by less conventional mechanisms. Common pathways involved in the pathogenesis of fatty liver and CAD includes hepatic insulin resistance and sub clinical inflammation. The hepatic insulin resistance state of fatty liver infiltration is characterized by increased FFA, which causes lipotoxicity and impairs endothelium-dependent vasodilatation, increases oxidative stress, and has a cardio toxic effect. Additional metabolic risk factors include leptin, adiponectin, pro inflammatory cytokines [such as IL-6, C-reactive protein and plasminogen activator inhibitor-1 (PAI-1)], which together lead to increased oxidative stress and endothelial dysfunction, finally promoting coronary artery disease (CAD). When classical risk factors are superimposed on fatty liver accumulation, they may further increase the new metabolic risk factors, exacerbating CAD. The clinical implication is that patients with NAFLD are at higher risk (steatohepatitis, diabetes, obesity, atherogenic dyslipidemia) and should undergo periodic cardiovascular risk assessment including the Framingham score, cardiac effort test, and measurement of intimae-media thickening of the carotids arteries. This may improve risk stratification for CAD.

Rosiglitazone versus rosiglitazone and metformin versus rosiglitazone and losartan in the treatment of nonalcoholic steatohepatitis in humans: a 12-month randomized, prospective, open- label trial

Medication combinations that improve the efficacy of thiazolidinediones or ameliorate weight-gain side effects of therapy represent an attractive potential treatment for (NASH). The aim of this randomized, open-label trial was to assess the efficacy of rosiglitazone and metformin in combination versus rosiglitazone and losartan, compared to rosiglitazone alone, after 48 weeks of therapy. A total of 137 subjects with biopsy-proven NASH were enrolled and randomly assigned to receive either 4 mg twice-daily of rosiglitazone, 4 mg of rosiglitazone and 500 mg of metformin twice-daily, or 4 mg of rosiglitazone twice-daily and 50 mg of losartan once-daily for 48 weeks. Patients were screened for other etiologies of chronic liver disease, including daily alcohol intake in excess of 20 g. Repeat liver biopsy was performed after 48 weeks of therapy and reviewed in a blinded fashion by a single expert hepatopathologist. The primary aim of the study was to assess for differences between treatment groups in the improvement of steatosis, hepatocellular inflammation, and fibrosis. In total, 108 subjects completed the trial. Primary outcome revealed no significant difference between treatment groups in all histologic parameters (steatosis, P = 0.137; hepatocellular inflammation, P = 0.320; fibrosis, P = 0.229). Overall improvement in steatosis, hepatocellular inflammation, ballooning degeneration, and fibrosis was observed (P ≤ 0.001). Serum aminotransferases were reduced in all three groups (P < 0.001 within treatment, P > 0.05 between groups). Metformin did not significantly mitigate weight gain (P = 0.051).

CONCLUSIONS

Forty-eight weeks of combination therapy with rosiglitazone and metformin or rosiglitazone and losartan confers no greater benefit than rosiglitazone alone with respect to histopathology.

Safety and impact on cardiovascular events of long-term multifactorial treatment in patients with metabolic syndrome and abnormal liver function tests: a post hoc analysis of the randomised ATTEMPT study

INTRODUCTION

Non-alcoholic fatty liver disease (NAFLD), a hepatic manifestation of metabolic syndrome (MetS), is common and accounts for 80% of cases of elevated liver function tests (LFTs). We assessed the long-term effects of multifactorial intervention on LFTs and their association with cardiovascular disease (CVD) events in patients with MetS without diabetes mellitus or CVD.

MATERIAL AND METHODS

This prospective, randomized, open label study included 1,123 patients (aged 45-65 years). Patients received intensive lifestyle intervention and pharmacotherapy: atorvastatin in all patients (low density lipoprotein cholesterol [LDL-C] targets of<100 mg/dl [group A] or<130 mg/dl [group B]), inhibitors of the renin-angiotensin-aldosterone axis for hypertension, metformin for dysglycaemia and orlistat for obesity.

RESULTS

Among participants, 326 had modestly elevated LFTs and ultrasonographic (US) evidence of NAFLD (165 patients in group A2 and 161 patients in group B2). The NAFLD resolved during the 42-month treatment period in 86% of patients in group A2 and in 74% of patients in group B2 (p<0.001). In both groups nearly 90% of patients attained lipid goals. Mean LDL-C and TG levels were higher in group B2 than in group A2 (p<0.001). There were no CVD events in group A2 whereas 5 non-fatal events occurred in group B2 (log-rank-p = 0.024). There were no major side-effects.

CONCLUSIONS

Attaining multiple treatment targets is safe and beneficial in primary prevention patients with MetS and NAFLD. Lipid levels and LFTs normalized, US findings associated with NAFLD resolved and no CVD events occurred in patients with LDL-C levels<100 mg/dl (group A2). Resolution of NAFLD might have contributed to the prevention of CVD events.

Current therapeutic strategies in non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) encompasses a spectrum of disease ranging from simple steatosis through steatohepatitis (NASH) to increasing fibrosis and eventual cirrhosis. NAFLD is the hepatic manifestation of the metabolic syndrome and has now become the most common cause of liver disease in Western countries, with the more advanced stages of disease being associated with an increased risk of liver-related morbidity and mortality. The optimal management of patients with NAFLD remains a clinical challenge. The aim of this study is to describe established and emerging strategies for the treatment of NAFLD. Relevant research and review articles were identified by searching PubMed. Selected articles referenced in these publications were also examined. Good quality randomized controlled studies have demonstrated the need for multifaceted lifestyle interventions in patients with NAFLD including the need for diet, exercise and behavioural counselling. Despite several trials of pharmacological agents, no highly effective treatment yet exists, with surgery representing the mainstay for advanced disease. A multidisciplinary approach, with a major focus on lifestyle change, represents best treatment pending the development of new therapeutic options.

Hepatic steatosis and Type 2 diabetes: current and future treatment considerations

Hepatic steatosis, considered the first step in the pathophysiologic continuum of non-alcoholic fatty liver disease, is estimated to afflict 30% of the US population and over 75% of patients with Type 2 diabetes. Given the expected rise in the prevalence of obesity and Type 2 diabetes in the following decades, hepatic steatosis will, if not already, become an epidemic. The consequences of hepatic steatosis are numerous, and range from progression to chronic liver disease, with its associated morbidity and mortality, to worsening insulin resistance and Type 2 diabetes, as well as being an independent contributor to cardiovascular disease. All such consequences are more likely to occur in patients with Type 2 diabetes who are already at high risk of cardiovascular events. In this article we review the evidence behind the available therapeutic options for hepatic steatosis, and identify challenges and unmet needs in the field.

Treatment of non-alcoholic fatty liver disease with focus on emerging drugs

INTRODUCTION

Non-alcoholic fatty liver disease (NAFLD) is becoming one of the most common causes of chronic liver disease worldwide. The economic and social cost of disease is very high and there is a need for effective treatments.

AREAS COVERED

The available and potential future treatments for NAFLD are reviewed.

EXPERT OPINION

Weight loss remains the cornerstone of treatment of hepatic steatosis, but difficult to pursue. A pragmatic approach relies on generic recommendations for weight loss and physical activity in the whole population and limiting interventions to subject at risk of disease progression, but the type of preferred treatment remains a matter of debate. The large number and mechanistic diversity of drugs that have so far been investigated bear testimony to the lack of a specific, effective agent. Insulin resistance remains the pivotal alteration responsible for liver disease and its progression and insulin sensitizers are regarded as the treatment of choice. Several ongoing studies are testing the effectiveness of new approaches on histological outcomes and new metabolic pathways are under scrutiny.

Non-alcoholic fatty liver disease (NAFLD): why you should care, when you should worry, what you should do

For the diabetologist, non-alcoholic fatty liver disease (NAFLD) is important at both ends of its spectrum. It is an early warning sign of future risk of metabolic syndrome, type 2 diabetes mellitus, and cardiovascular disease. It may also lead to late life-threatening sequela of diabetes mellitus in the event of progression to liver failure or hepatocellular carcinoma. This review will highlight the recent progress in understanding the natural history of non-alcoholic fatty liver disease and in developing a rational approach to its diagnosis, staging, and management. The pandemic prevalence of non-alcoholic fatty liver disease in Western countries necessitates both a high index of suspicion to identify cases and a non-invasive approach to staging, which is best achieved with clinical/biochemical panels and transient elastography. Lifestyle modification is the cornerstone of management. Recent clinical trials provide support for pharmacologic therapies directed at the metabolic syndrome and at protecting the liver but more data are needed. Bariatric surgery is appropriate for high-risk patients who fail conservative management. Patients with liver failure or hepatocellular carcinoma may be candidates for liver transplantation.

Nonalcoholic fatty liver disease and diabetes mellitus: pathogenesis and treatment

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.

Insulin resistance in nonalcoholic steatohepatitis: necessary but not sufficient - death of a dogma from analysis of therapeutic studies?

Studies on pathogenesis tend to blame insulin resistance as the chief pathogenic agent in the development and progression of nonalcoholic steatohepatitis (NASH). In this article, studies reporting histological changes induced by pharmacological therapy and nonpharmacological interventions in NASH are critically reviewed, assuming that analysis of morphological findings can provide further insight into the pathogenesis of NASH. PubMed database analysis provided 16 studies describing light microscopy in adults and three in children; ultrastructural analysis was conducted through electron microscopy in two human and four animal studies. Analysis of the data disclosed methodological issues, such as variable histological criteria, limited series, failure to stratify enrolled patients for their risk of progression and very few electron microscopy studies. Moreover, no particularly convincing 'proof-of-concept' study that might assist in understanding the pathogenesis of NASH was found. It is noteworthy that insulin sensitizers fail to treat NASH in all cases, do not reverse or even worsen mitochondrial abnormalities in NASH and, conversely, histological improvement of disease, at least in some patients, is observed with agents acting through mechanisms other than insulin sensitization, such as vitamin E. The finding that correction of insulin resistance may not be sufficient to successfully treat NASH in the majority of patients seems to conflict with studies on pathogenesis. This might imply that NASH is the shared end result of varying pathogenic mechanisms concurring to determine liver damage to a variable extent in the individual patients. If this hypothesis is true, we should try to tailor treatment to each subject.

Pharmacological therapy of nonalcoholic steatohepatitis

Nonalcoholic steatohepatitis (NASH), unlike simple steatosis, is a potentially progressive disease. Various types of drugs have been explored for the treatment of NASH. We reviewed the various therapies available, with particular emphasis on their efficacy for the improvement of hepatic fibrosis. Treatments for NASH included lipase-inhibiting agents, drugs that target components of metabolic syndrome, antioxidants, liver cytoprotectants, and suppressors of inflammatory cytokines. Alanine transaminase levels were significantly decreased and the grade of histologic features other than fibrosis was significantly improved in more than 75% of treatment arms across studies, yet the stage of liver fibrosis was significantly improved in less than 30% of treatment arms. Recently, drugs such as peroxisome proliferator-activated receptor-γ agonists have received attention for their anti-fibrotic effect. However, due to a lack of large-scale, high quality, long-term clinical trials, the utility of any particular treatment for NASH is not yet clear. Further clinical studies are needed to evaluate the efficacy and safety of individual drugs.

Novel treatment modalities for nonalcoholic steatohepatitis

Nonalcoholic steatohepatitis (NASH) is the most common cause of chronic liver disease in the Western world. It can lead to cirrhosis and hepatocellular cancer, and is independently associated with an increased risk of death due to cardiovascular and liver diseases. Over the past 5 years, numerous advances in understanding its pathogenesis have been made, providing a rationale for translation of this information into clinical trials. Although the optimum therapy is still awaited, there is strong evidence to support the use of vitamin E in selected subjects. Many other potential therapeutic options are now available. In this paper, we review the status of both current and emerging therapeutic strategies for patients with NASH.

Pleiotropic effects of angiotensin receptor blockers: addressing comorbidities by optimizing hypertension therapy

The efficacy of angiotensin receptor blockers (ARBs) in the management of hypertension is well established. Whether these agents induce pleiotropic effects that promote the amelioration of vascular disorders independent of blood pressure reduction remains controversial. This review examines preclinical and clinical data that highlight a potentially important role for ARBs in several common vascular disorders, including cardiovascular, cerebrovascular, renal, and metabolic disorders. The preponderance of evidence suggests that some of the benefits derived from ARBs might improve outcomes in these disorders by actions that extend beyond blood pressure reduction. This review also identifies some potentially important differences in the mechanism of action between ARBs and angiotensin-converting enzyme inhibitors that may have clinical significance in the management of vascular diseases.

A meta-analysis of randomized trials for the treatment of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) encompasses a histological spectrum ranging from simple steatosis to nonalcoholic steatohepatitis (NASH). NAFLD carries a higher risk of cardio-metabolic and liver-related complications, the latter being confined to NASH and demanding specific treatment. We assessed the efficacy of proposed treatments for NAFLD/NASH by reviewing reports of randomized controlled trials (RCTs) on online databases and national and international meeting abstracts through January 2010. Primary outcome measure was histological improvement; secondary outcome was biochemical improvement; improvement in radiological steatosis was also evaluated. Two reviewers extracted articles using predefined quality indicators, independently and in duplicate. Main outcomes of randomized controlled trials (RCTs) were pooled using random-effects or fixed-effects models. Publication bias was assessed by funnel plots. Forty-nine RCTs (30 in NASH) were included: 23 RCTs (22 in NASH, 1 in NAFLD) had post-treatment histology. Most RCTs were small and did not exceed 1-year duration. Weight loss, thiazolidinediones (especially pioglitazone), and antioxidants were most extensively evaluated. Weight loss was safe and dose-dependently improved histological disease activity in NASH, but more than 50% of patients failed to achieve target weight loss. Thiazolidinediones improved steatosis and inflammation but yielded significant weight gain. RCTs with antioxidants yielded conflicting results and were heterogeneous with respect to type and dose of drug, duration, implementation of lifestyle intervention. Among the other agents, pentoxifylline, telmisartan and L-carnitine improved liver histology in at least 1 RCT in NASH; polyunsaturated fatty acid (PUFA) ameliorated biochemical and radiological markers of NAFLD. Other approaches yielded negative results.

CONCLUSION

Well-designed RCTs of adequate size and duration, with histological endpoints, are needed to assess long-term safety and efficacy of proposed treatments on patient-oriented clinical outcomes.

Non-alcoholic fatty liver disease from pathogenesis to management: an update

Non-alcoholic fatty liver disease (NAFLD), the most common chronic liver disease in the Western world, is tightly associated with obesity and metabolic syndrome. NAFLD entails an increased cardiometabolic and liver-related risk, the latter regarding almost exclusively non-alcoholic steatohepatitis (NASH), the progressive form of NAFLD. Pathogenetic models encompass altered hepatic lipid partitioning and adipokine action, increased oxidative stress, free fatty acid lipotoxicity. On this basis, lifestyle-, drug- or surgically induced weight loss, insulin sensitizers, antioxidants, lipid-lowering drugs have been evaluated in NAFLD/NASH. Most trials are small, of short duration, nonrandomized, without histological end points, thus limiting assessment of long-term safety and efficacy of proposed treatments. All NAFLD patients should be evaluated for their metabolic, cardiovascular and liver-related risk. Liver biopsy remains the gold standard for staging NAFLD, but non-invasive methods are under intense development. Weight loss through lifestyle intervention is the initial approach, because of established efficacy on NAFLD-associated cardiometabolic abnormalities, and to emerging benefits on necroinflammation and overall disease activity in NASH. Bariatric surgery warrants further evaluation before it can be routinely considered in morbidly obese NASH. Larger- and longer-duration randomized trials assessing safety and benefits of drugs on patient-oriented outcomes are needed before pharmacological treatment can be routinely recommended for NASH.

Pharmacological and non-pharmacological treatment of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) comprises a disease spectrum ranging from simple steatosis and steatohepatitis to cirrhosis. Based on its strongest risk factors namely visceral obesity and insulin resistance, NAFLD is thought to be the hepatic manifestation of the metabolic syndrome and is considered to be the most common liver disorder in Western countries. Pathophysiological mechanisms include an enlarged pool of fatty acids, subclinical inflammation, oxidative stress and imbalances of various adipocytokines such as adiponectin. Accordingly, targets for therapeutic interventions are miscellaneous: amelioration of obesity by pharmacological, surgical or lifestyle intervention has been evaluated with success in numerous, but not all studies. Some efficacy was reported for metformin and short-term glitazone treatment. In a large recently reported trial, vitamin E supplementation improved biochemical and histological markers in subjects with non-alcoholic steatohepatitis. Blockade of the endocannabinoid system has been proposed to be a promising target in NAFLD; however, very recently the cannabinoid receptor blocker rimonabant has been withdrawn because of central nervous system toxicity. Cytoprotective therapies and statins have been mainly ineffective in NAFLD. New but so far insufficiently studied therapeutic approaches include inhibitors of the renin-angiotensin system as well as incretin mimetics respectively.

Review article: omega-3 fatty acids - a promising novel therapy for non-alcoholic fatty liver disease

BACKGROUND

Non-alcoholic fatty liver disease affects 10-35% of the adult population worldwide; there is no consensus on its treatment. Omega-3 fatty acids have proven benefits for hyperlipidaemia and cardiovascular disease, and have recently been suggested as a treatment for non-alcoholic fatty liver disease.

AIMS

To review the evidence base for omega-3 fatty acids in non-alcoholic fatty liver disease and critically appraise the literature relating to human trials.

METHODS

A Medline and PubMed search was performed to identify relevant literature using search terms 'omega-3', 'N-3 PUFA', 'eicosapentaenoic acid', 'docosahexaenoic acid', 'non-alcoholic fatty liver disease' and 'NAFLD'.

RESULTS

Omega-3 fatty acids are important regulators of hepatic gene transcription. Animal studies demonstrate that they reduce hepatic steatosis, improve insulin sensitivity and reduce markers of inflammation. Clinical trials in human subjects generally confirm these findings, but have significant design inadequacies.

CONCLUSIONS

Omega-3 fatty acids are a promising treatment for non-alcoholic fatty liver disease which require to be tested in randomized placebo-controlled trials.

Irbesartan has no short-term effect on insulin resistance in hypertensive patients with additional cardiometabolic risk factors (i-RESPOND)

AIMS

Intervention studies have shown that angiotensin receptor blockers (ARB) may reduce the incidence of type 2 diabetes mellitus. It is currently unclear whether short-term therapy with ARBs affects metabolic parameters.

METHODS

i-RESPOND, a randomised, controlled, multicentre, double-blind study evaluated the effect of 16 weeks of irbesartan vs. hydrochlorothiazide (HCTZ) on insulin resistance as well as on lipid and inflammatory parameters in hypertensive subjects with metabolic syndrome. Patients received irbesartan (150 mg/d; n = 211) or HCTZ (12.5 mg/d; n = 215), titrated to 300 mg/day and 25 mg/day respectively. In a second part of the study (weeks 16-28), patients initially randomised to irbesartan received additional HCTZ and vice versa.

RESULTS

At week 16 both irbesartan and HCTZ had no effect on insulin resistance measured by the Matzuda index and beta-cell function. Similarly, in the second part of the study (week 16-28) no differences between irbesartan and HCTZ with respect to glucose metabolism were observed. However, irbesartan induced beneficial changes in high-sensitivity-C-reactive protein (hs-CRP) (irbesartan: -5.5 +/- 5.2%; HCTZ + 19.9 +/- 6.5%, p = 0.0024) and in urinary albumin/creatinine ratio (ACR) (irbesartan: -13%; HCTZ + 9%; p = 0.0041) compared with HCTZ despite a similar decrease in blood pressure in both treatment groups. Irbesartan and HCTZ were well tolerated and adverse events were comparable.

CONCLUSION

Irbesartan did not show significant favourable effects on insulin resistance compared with HCTZ in this study; however, may have beneficial effects on inflammation and microalbuminuria in hypertensive patients with metabolic syndrome.