Association of chronic viral hepatitis B with insulin resistance

The interplay between chronic hepatitis B and diabetes mellitus: A narrative and concise review

Type 2 diabetes mellitus (T2DM) is a prevalent metabolic disorder among individuals with chronic hepatitis B (CHB), contributing to additional adverse impacts on both hepatic and extrahepatic systems. Existing evidence suggests a potential positive association between CHB and the development of insulin resistance and T2DM. The presence of T2DM in CHB patients is associated with an increased risk of liver fibrosis, cirrhosis, decompensation, and hepatocellular carcinoma (HCC) occurrence. Moreover, it elevates the risk of non-liver cancers and all-cause mortality in this population. T2DM also serves as the key element in metabolic dysfunction-associated steatotic liver disease, which is prevalent in the CHB population. Although specific guidelines for managing T2DM in CHB patients have not been proposed, some studies indicated that intensive glycemic control may benefit the prognosis of these patients. Additionally, specific antidiabetic agents, such as metformin and thiazolidinediones, promise to reduce HCC risk. However, unresolved questions, including the optimal glycemic control target and the selection of antidiabetic agents for CHB patients, remain and thus warrant further investigations through well-designed prospective trials. Implementing a standardized protocol encompassing regular monitoring, risk stratification, and early intervention using a multidisciplinary framework may improve the outcomes of diabetic CHB patients.

Concomitant Diseases and Co-contribution on Progression of Liver Stiffness in Patients with Hepatitis B Virus Infection

BACKGROUND

The association between hepatitis B and concomitant diseases, such as fatty liver, T2DM, MetS, and Hp infection, remains unclear.

AIM

The present study was to illustrate the association and explore the co-contribution on abnormal transaminase and progression of liver stiffness.

METHODS

A total of 95,998 participants underwent HBsAg screening in West China Hospital from 2014 to 2017. Multivariable logistic regression was used to determine the adjusted odds ratios.

RESULTS

The prevalence of HBsAg-positive rate was 8.30% of our included study population. HBsAg positive was associated with negative risk of fatty liver (odds ratio [OR] 0.71, 95% confidence interval [CI] 0.65-0.78, p < 0.001) and MetS (OR 0.74, 95% CI 0.67-0.84, p < 0.001), and with positive risk of Hp infection (OR 1.09, 95% CI 1.02-1.17, p = 0.012) and T2DM (OR 1.18, 95% CI 1.01-1.40, p = 0.043). Besides, HBsAg-positive patients with T2DM had higher risk of elevated ALT (OR 2.09, 95% CI 1.69-2.83, p < 0.001 vs OR 1.59, 95% CI 1.51-1.68, p < 0.001), AST (OR 2.69, 95% CI 1.98-3.65, p < 0.001 vs OR 1.89, 95% CI 1.76-2.02, p < 0.001) than HBV alone. In addition to HBV, T2DM also can increase the risk of liver fibrosis (OR 3.23, 95% CI 1.35-7.71, p = 0.008) and cirrhosis (OR 4.31, 95% CI 1.41-13.20, p = 0.010).

CONCLUSION

Hepatitis B patients have a lower risk of fatty liver and MetS, and a higher risk of T2DM and Hp infection. Besides, T2DM might be possibly associated with abnormal liver transaminase and fibrosis progression in HBsAg-positive patients.

Hepatitis C is associated with more adverse pregnancy outcomes than hepatitis B: A 7-year national inpatient sample study

Prior international studies have shown mixed results regarding the association of hepatitis B and hepatitis C with adverse pregnancy outcomes. We performed an updated evaluation of the prevalence of associated adverse pregnancy outcomes and evaluated trends over time of diagnosis of chronic hepatitis B (HBV) and chronic hepatitis C (HCV) in pregnant women in a national database. All pregnant women with HBV and HCV were identified from the National Inpatient Sample database 2012 to 2018. Multivariate logistic regression analyses were performed to compare pregnancy‐related complications, including rates of preeclampsia/eclampsia, gestational diabetes, intrauterine growth restriction, antepartum/intrapartum hemorrhage, preterm labor, and Cesarean section. We evaluated all‐cause in‐hospital mortality, length of stay, and total cost of hospitalizations. A total of 28.7 million pregnancy‐related hospitalizations that met our eligibility criteria were identified, including 51,200 with HBV and 131,695 with HCV. In comparison with the uninfected controls, the HBV group was significantly more likely to develop gestational diabetes (12.94% vs. 6.94%, p < 0.001). The HCV group was more likely to have preterm labor (9.63% vs. 6.27%, p < 0.001), intrauterine growth restriction (6.04% vs. 2.89%, p < 0.001), longer length of stay (3.4 days vs. 2.7 days, p < 0.001), and higher hospitalization cost (15,052 dollars vs. 14,258 dollars, p < 0.001). These findings should inform counseling of women who are found to have HBV or HCV during pregnancy regarding the risk of adverse pregnancy outcomes and support the need for an interdisciplinary approach to optimize maternal and neonatal outcomes.

Association of serum 25-hydroxyvitamin D3 levels and insulin resistance with viral load and degree of liver fibrosis in Egyptian chronic HBV patients: a case-control study

Aim of the study

To assess serum 25-hydroxyvitamin D₃ level and insulin resistance (IR) in hepatitis B virus (HBV) patients compared with controls and to evaluate the correlation with HBV viral load, severity of liver disease and degree of liver fibrosis.

Material and methods

A case-control study. Sixty HBV patients and 60 controls were enrolled. Chemiluminescence was used to determine 25-hydroxyvitamin D₃ levels. Insulin resistance was evaluated using the homeostasis model assessment method. Polymerase chain reaction was used to quantify HBV viral loads. Severity of liver disease was assessed by Child-Pugh scores. Transient elastography was used to evaluate the degree of liver fibrosis.

Results

25-Hydroxyvitamin D₃ deficiency is more prevalent among HBV patients compared to controls. 25-Hydroxyvitamin D₃ levels declined considerably as viral load rose (p < 0.001). 25-Hydroxyvitamin D₃ level declined as liver fibrosis progressed (34.0 ±0.0 ng/ml in F1 vs. 12.67 ±8.0 ng/ml in F4) and the severity of the disease increased (22.75 ±6.36 ng/ml in Child A vs. 5.50 ±0.58 ng/ml in Child C). Insulin resistance is more prevalent among HBV patients compared to controls and it appeared to deteriorate progressively with boosting of the viral load, degree of fibrosis and severity of liver disease (p < 0.001).

Conclusions

HBV patients had significantly lower 25-hydroxyvitamin D₃ levels compared to healthy individuals and HBV infection is associated with IR. 25-Hydroxyvitamin D₃ deficiency and IR were associated with HBV viral loads, severity of liver disease, and degree of liver fibrosis.

[Hepatitis B and C: mechanisms of virus-induced liver pathogenesis and tumorigenesis]

Worldwide, the hepatitis B and hepatitis C viruses (HBV, HCV) are the most relevant causative viral agents of a chronic hepatitis (inflammation of the liver). At present, more than 250 million people suffer from a chronic HBV infection globally, resulting in 0.8 million deaths per year. A chronic HCV infection accounts for about 70 million cases worldwide, leading to a death toll of about 1 million per year. An approved vaccine is only available against an HBV infection. Both HBV and HCV infections result in a highly increased risk of developing liver fibrosis, cirrhosis, and a hepatocellular carcinoma (HCC).This review aims to describe mechanisms of the HBV- and HCV-associated pathogenesis. The focus is on the interplay between a chronic infection with intracellular signaling transduction, metabolic pathways with an emphasis on lipid metabolism, the establishment of liver fibrosis and cirrhosis during a chronic infection, and the mechanisms of the onset of a virally induced HCC.Despite there being great advances in the characterization of viral life cycles and the development of robust antiviral strategies, significant hurdles persist: gaining a better understanding of the mechanisms that drive virus-associated pathogenesis as well as increasing insights regarding different viral genotypes having impacts on alternate pathogeneses.

HBV infection is a risk factor for chronic kidney disease: Systematic review and meta-analysis

BACKGROUND

The activity of hepatitis B virus (HBV) as a risk factor for the incidence and progression of chronic kidney disease (CKD) has not been clarified.

AIM

We evaluated the impact of infection with HBV on the risk of CKD in the general population.

MATERIAL AND METHODS

We carried out a systematic review of the published medical literature to assess whether a relationship between hepatitis B infection and an increased risk of CKD in the adult general population occurs. We adopted the random effects model of DerSimonian and Laird to provide a summary estimate of the risk of chronic kidney disease (defined by lowered glomerular filtration rate and/or detectable proteinuria) with HBV infection across the published studies. Meta-regression and stratified analyses were also performed.

RESULTS

We retrieved 33 studies (n = 7,849,849 patients) published in 26 different articles, and separate meta-analyses were performed according to the outcome. Pooling results from cohort studies (11 studies, n = 1,056,645 patients) demonstrated a relationship between positive HBV serologic status and increased incidence of CKD, the summary estimate for adjusted HR with HBV across the surveys, 1.40 (95% CI, 1.16-1.69) (P < .001). Between-study heterogeneity was noted (Q value, 49.5, P < .0001). No relationship between HBV and prevalence of CKD was noted in the subset of cross-sectional studies (10 studies; n = 3,222,545 patients), adjusted OR, 1.04 (95% IC 0.90-1.218; P = .5). Meta-regression analysis reported a relationship between positive HBsAg status and incidence of CKD in the general population (P < .015).

CONCLUSIONS

It appears that exposure to HBV infection seems to be associated with an increased risk of developing CKD in the adult general population. Studies aimed to understand the mechanisms responsible of such association are under way.

Glucose Homeostasis Is Dysregulated in Ducks Infected with Duck Hepatitis B Virus

INTRODUCTION

The association between hepatitis B virus (HBV) infection and the development of diabetes remains controversial. This study examined the effect of HBV infection on glucose homeostasis using a duck HBV (DHBV) model.

METHODS

Plasma DHBV DNA was detected by quantitative polymerase chain reaction (PCR). Tissue infection of DHBV was determined by detecting DHBV covalently closed circular DNA (cccDNA) with a method of rolling circle amplification combined with cross-gap PCR, and verified by fluorescence in situ hybridization assay. An intravenous injection glucose tolerance test (GTT) was used to analyze the effect of DHBV infection on glucose tolerance.

RESULTS

Of the finally included 97 domestic ducks, 53 (54.6%) were congenitally infected by DHBV. The positive rate of DHBV cccDNA in the liver, kidney, pancreas, and skeletal muscle of the infected ducks was 100, 75.5, 67.9, and 47.2%, respectively. The DHBV-infected ducks had higher blood glucose levels at 15 and 30 min post-load glucose (p < 0.01 and p < 0.001, respectively) in the GTT, much more individuals with greater glucose area under curve (p < 0.01), and a 57% impaired glucose tolerance (IGT) rate, as compared with noninfected controls. In addition, the subgroups of the infected ducks with DHBV cccDNA positive in skeletal muscle maintained the higher blood glucose level up to 2 h post-load glucose during the GTT and had a 76% IGT rate.

CONCLUSION

These results suggest that DHBV intrahepatic and extrahepatic infection impairs glucose tolerance, and thus evidence the association of DHBV infection with the dysregulation of glucose metabolism.

Evaluation of the Relationship between Insulin Resistance and HBV DNA Level in Patients with HBeAg-negative Chronic HBV Infection (Natural Course Phase 3)

Background and aims

Chronic hepatitis B (CHB) infection is an important cause of morbidity and mortality worldwide with an increased risk of liver failure, cirrhosis, and hepatocellular carcinoma. Hepatitis B virus (HBV) DNA level, the marker of viral load in the host, is a parameter affected by host factors. In this study, we investigated the relationship between HBV DNA level and insulin resistance as a host factor.

Methods

In this study, 146 patients diagnosed with “HBeAg-negative chronic HBV infection” (natural course phase 3, inactive carrier) according to the European Association for the Study of the Liver (EASL) 2017 guidelines were retrospectively analyzed and demographic, anthropometric, histopathological, radiological and laboratory data of the patients were recorded. Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) levels of the patients were calculated, and according to the value, the patients were divided into two groups as insulin resistant and non-insulin resistant. All parameters, including HBV DNA, were evaluated and compared between the two groups.

Results

77 patients (52.7%) were insulin resistant with a HOMA-IR value of 2.5 or more. The remaining 69 patients (47.3%) whose HOMA-IR value less than 2.5 were non-insulin resistant. The median HBV DNA was 410 IU in the insulin-resistant group and 350 IU in the other group, and there was no statistical significance between the two groups (p: 0.537). HBV DNA level was only positive correlated with HBsAg level and negatively correlated with anti-Hbs level and age (p < 0.005). Compared to the non-insulin resistant group, body mass index (BMI), presence of hepatosteatosis on ultrasonography (USG), fasting blood sugar, fasting insulin, total protein, gamma glutamyl transferase (GGT), triglyceride (TG), very-low-density lipoprotein (VLDL), uric acid level, triglyceride/high-density lipoprotein (HDL) ratio were significantly higher and HDL levels were significantly lower in the insulin-resistant group (p < 0.005). GGT levels and TG/HDL ratio were found to be higher in patients with hepatosteatosis on ultrasonography than in patients without hepatosteatosis (p < 0.005). TG/HDL ratio was found to be an independent factor in predicting insulin resistance and every 1 unit increase of this ratio increases the risk of developing insulin resistance 2.1 times.

Conclusion

In this study, no significant relationship was found between insulin resistance and HBV DNA levels in chronic inactive HBV carriers. In addition, insulin resistance was observed more frequently in these patients compared to the general population, and insulin resistance was found to be associated with high BMI, hepatosteatosis rate, VLDL, TG, GGT, total protein, uric acid, TG/HDL ratio, and low HDL. TG/HDL ratio was found to be successful in predicting insulin resistance.

How to cite this article

Senoymak MC, Ozkan H. Evaluation of the Relationship between Insulin Resistance and HBV DNA Level in Patients with HBeAg-negative Chronic HBV Infection (Natural Course Phase 3). Euroasian J Hepatogastroenterol 2020;10(2):85–91.

Serum concentrations of selected adipokines in virus-related liver cirrhosis and hepatocellular carcinoma

Aim of the study

Hepatotropic viruses cause metabolic disturbances such as insulin resistance and hepatosteatosis. Moreover, metabolic factors, such as insulin resistance, obesity, and type 2 diabetes mellitus, increase the risk for hepatocellular carcinoma (HCC) in patients with virus-related liver cirrhosis. Cytokines secreted by the adipose tissue (adipokines) may be implicated in these metabolic disturbances, but there is little evidence regarding the role of adipokines in virus-related cirrhosis and HCC. Thus, we studied whether serum concentrations of selected adipokines were altered in patients with virus-related liver cirrhosis, including patients with HCC.

Material and methods

We included 43 patients with liver cirrhosis due to chronic hepatitis B or chronic hepatitis C. Of these patients, 36 had HCC and 7 did not have any malignant lesions. In addition to routine clinical and laboratory variables, we analyzed serum concentrations of betatrophin, insulin, vaspin, visfatin, and irisin.

Results

Compared with healthy controls, patients with HCC had significantly increased vaspin concentrations and significantly reduced irisin concentrations. Compared with controls, patients with virus-related cirrhosis, with or without HCC, had significantly increased concentrations of insulin and betatrophin. The serum visfatin concentration was non-significantly higher in patients with virus-related cirrhosis than in controls. None of the studied adipokines was a significant predictor of HCC. Serum concentrations of the studied adipokines were not related to cirrhosis severity or HCC stage.

Conclusions

Metabolic parameters, including serum adipokine concentrations, are altered in patients with virus-related liver cirrhosis. Adipokines might be related to the HCC risk in these patients.

HBV infection is a risk factor for chronic kidney disease: Systematic review and meta-analysis

BACKGROUND

The activity of hepatitis B virus (HBV) as a risk factor for the incidence and progression of chronic kidney disease (CKD) has not been clarified.

AIM

We evaluated the impact of infection with HBV on the risk of CKD in the general population.

MATERIAL AND METHODS

We carried out a systematic review of the published medical literature to assess whether a relationship between hepatitis B infection and an increased risk of CKD in the adult general population occurs. We adopted the random effects model of DerSimonian and Laird to provide a summary estimate of the risk of chronic kidney disease (defined by lowered glomerular filtration rate and/or detectable proteinuria) with HBV infection across the published studies. Meta-regression and stratified analyses were also performed.

RESULTS

We retrieved 33 studies (n=7,849,849 patients) published in 26 different articles, and separate meta-analyses were performed according to the outcome. Pooling results from cohort studies (11 studies, n=1,056,645 patients) demonstrated a relationship between positive HBV serologic status and increased incidence of CKD, the summary estimate for adjusted HR with HBV across the surveys, 1.40 (95% CI, 1.16-1.69) (P<.001). Between-study heterogeneity was noted (Q value, 49.5, P<.0001). No relationship between HBV and prevalence of CKD was noted in the subset of cross-sectional studies (10 studies; n=3,222,545 patients), adjusted OR, 1.04 (95% IC 0.90-1.218; P=.5). Meta-regression analysis reported a relationship between positive HBsAg status and incidence of CKD in the general population (P<.015).

CONCLUSIONS

It appears that exposure to HBV infection seems to be associated with an increased risk of developing CKD in the adult general population. Studies aimed to understand the mechanisms responsible of such association are under way.

Systematic review: chronic viral hepatitis and metabolic derangement

BACKGROUND

The liver has a critical role in the metabolism of glucose and lipids. Chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infection leads to a spectrum of liver disease including chronic hepatitis, cirrhosis and hepatocellular carcinoma. Metabolic syndrome (MetS) has a rising incidence owing to an epidemic of type 2 diabetes mellitus (T2DM) and obesity. Non-alcoholic fatty liver disease is a liver manifestation of MetS and has become the most common cause of chronic liver disease worldwide.

AIM

To summarise the interplay among hepatitis viruses, MetS and its components.

METHODS

We searched the literature about HBV, HCV infection, MetS, fatty liver and its components from PubMed.

RESULTS

With respect to the viral replication cycle, lipids are important mediators between viral entry and hepatocyte in HCV infection, but not in HBV infection. Thus, HCV infection is inversely associated with hyperlipidaemia and lipid rebound occurs following sustained viral response induced by interferon-based therapy or direct antiviral agents. In addition, HCV infection is positively associated with insulin resistance, hepatic steatosis, MetS and the risk of T2DM and atherosclerosis. In contrast, HBV infection may protect infected subjects from the development of MetS and hepatic steatosis. Accumulating evidence suggests that HBV infection is inversely associated with lipid metabolism, and exhibits no conclusive association with insulin resistance or the risk of T2DM and arteriosclerosis.

CONCLUSIONS

In patients with viral hepatitis and concurrent metabolic diseases, a multidisciplinary approach should be given rather than simply antiviral treatment.

Insulin Resistance Associated Disorders Pivoting Long-Term Hepatitis B Surface Antigen Decline During Entecavir Therapy

Insulin resistance associated disorders (IRAD), including prediabetes, type 2 diabetes mellitus (T2DM), and fatty liver are significant risk factors of liver-related death in chronic hepatitis B (CHB). However, their relationship remains unclear. We aimed to evaluate how IRAD influence the kinetics of serum hepatitis B surface antigen (HBsAg) in patients with CHB during long-term entecavir treatment. We enrolled 140 patients with CHB receiving at least 3 years of consecutive entecavir treatment in this retrospective study. A linear mixed effects model was adopted to examine the effects of variables and their interaction over time on the HBsAg trajectory. Furthermore, we acquired cytokine profiles and baseline fibrosis-4 index (FIB-4) scores for in-depth analysis. The median treatment time was 6.90 (4.47–9.01) years. Multivariate analysis revealed that older patients or those with prediabetes or T2DM had a significantly slower HBsAg decline over time (p = 0.0001 and p < 0.0001, respectively). Conversely, advanced fatty liver engendered a more rapid HBsAg decrease (p = 0.001). Patients with prediabetes or T2DM possessed higher IP-10 levels six years after entecavir therapy (p = 0.013). Compared to patients without prediabetes or T2DM, diabetic patients had more unfavorable features at the baseline, especially higher FIB-4 scores. Prediabetes or T2DM delays the clearance of HBsAg, but advanced hepatic fatty change counterbalances the effect. Additionally, IRAD could cause hepatic sequelae in CHB through immune-metabolic pathways.

Assessment of Hepatic Steatosis in Patients with Chronic Hepatitis B Using Fibroscan and its Relation to Insulin Resistance

Background & Aim:

Simple hepatic steatosis is a benign condition, but it may cause serious liver damage as it may lead to steatohepatitis, fibrosis and cirrhosis. The Controlled Attenuation Parameter (CAP) of fibroscan assesses hepatic steatosis. The aim of this work was to assess hepatic steatosis in patients with chronic hepatitis B infection using FibroScan and to detect its relation to insulin resistance.

Methods:

Seventy-seven patients with chronic HBV were enrolled in this study. Body mass index, complete lipid profile, fasting insulin, HOMA-IR, pelviabdominal ultrasound and fibroscan were assessed in all patients.

Results:

According to the presence of significant steatosis, seventy-seven patients enrolled in this study were divided into different groups, such as group I 47 patients (61.04%) with CHB virus infection with non-significant steatosis and group II 30 patients (38.96%) with CHB infection with significant steatosis. There was a statistically significant increase in fasting insulin and HOMA-IR in group II (p-value <0.001). CAP results ranged from 100-396 db/m with no significant difference in liver stiffness measurements in two studied groups (P value= 0.886). There was a significant positive correlation between the degree of hepatic steatosis measured by fibroscan and fasting insulin blood level, HOMA-IR, serum cholesterol and LDL. At cutoff > 222 db/m steatosis measured by fibroscan had a sensitivity of 63.33% and specificity of 82.35% for the detection of insulin resistance.

Conclusion:

In CHB infected patients, steatosis measurement by fibroscan was a strong predictor of Insulin Resistance (IR) and vice versa.

Effect of Non-alcoholic Fatty Liver Disease on Transaminase Levels and Transient Elastography in Patients with Chronic Hepatitis B

Objective To investigate the effects of non-alcoholic fatty liver disease on aminotransferase (ALT) levels and transient elastography in patients with chronic hepatitis B (CHB). Methods A cross-sectional study of 230 patients with CHB and ALT levels up to two times the upper limits of normal, of one-year duration, from June 2018 to May 2019. The demographic, clinical, and laboratory characteristics of each patient were collected. Transient elastography was performed to evaluate controlled attenuation parameter (CAP or steatosis) and liver stiffness (fibrosis). Results A total of 161 (70%) patients were overweight, with over two-thirds (166; 72.2%) having elevated ALT >35 U/L. Three-fourths of the patients (178; 77.4%) had a hepatitis B virus (HBV) deoxyribonucleic (DNA) level of less than 2000 IU/ml. Steatosis was detected in 166 (72.2%) patients while fibrosis of F2 or more in 88 (38.3%). Multivariate regression analysis showed that weight, homeostatic model assessment of insulin resistance (HOMA-IR), and elevated ALT levels of more than 35 were independently associated with higher CAP values (p= 0.019, 0.001, and 0.004, respectively). Age, insulin levels, and platelet counts were independently associated with liver elasticity (p=0.00, 0.002, and 0.028, respectively). HBV DNA levels did not show any significant association with CAP score, liver stiffness, and HOMA-IR or ALT level. Among those with an elevated ALT of 35 or above (n=166), 124 patients had HBV DNA levels less than 2000 IU/ml. Out of these, 97 (78.2%) patients had steatosis and 51 (41.1%) had F2 or more fibrosis. Conclusion A significant number of patients with CHB with mildly elevated ALT levels are overweight, have significant steatosis and fibrosis, but low HBV DNA levels. This aspect is important while making decisions regarding hepatitis B treatment.

Protective Effect of Hepatitis B Against Metabolic Syndrome in Patients with Nonalcoholic Fatty Liver Disease But Not in Normal Individuals

Background: Both hepatitis B (HB) and nonalcoholic fatty liver disease (NAFLD) are related to metabolic syndrome (MetS); however, this relationship remains controversial. In this study, we determined the effects of NAFLD and HB infection on the risk of MetS among elderly individuals. Methods: In total, 24,500 individuals aged >65 years were enrolled; they were classified into four groups: normal individuals (N), patients with only HB infection without abnormal echogenicity (HB-alone), patients with only abnormal echogenicity or fatty liver alone (FL-alone), and patients with both HB infection and abnormal echogenicity (HB-FL). Results: After adjustment for age, compared with group N, men and women with NAFLD (FL-alone and HB-FL) had a significantly higher risk of MetS, whereas no significant difference was observed in the incidence of MetS between groups HB-alone and N. However, group HB-FL had a lower risk of MetS than did group FL-alone. HB infection (HB-alone and HB-FL) was associated with a lower risk of high triglycerides (TGs) and fasting plasma glucose (FPG) than HB infection absence (groups N and FL-alone) in men and women. Lower risk of TG derangement was observed in group HB-alone than in group N. In addition, both men and women in group HB-FL had a lower risk of TG and FPG abnormalities than in group FL-alone, whereas a decrease in incidence of high waist circumference and blood pressure was observed only in men. Conclusion: HB infection protects against MetS development, only in patients with HB infection and NAFLD, but not in normal individuals. Additional studies are warranted to clarify the pathogenesis.

The Effects of Hepatic Steatosis on the Natural History of HBV Infection

Fatty liver prevalence is increasing and becoming a global health burden. Chronic hepatitis B infection (CHB) is one of the most common chronic viral infections. Steatosis in CHB patients increases risk of cirrhosis and hepatocellular carcinoma. Data from studies on the interaction between CHB and nonalcoholic fatty liver disease are not conclusive. Liver biopsy is the gold standard for diagnosis of fatty liver; however, noninvasive diagnostic tests have been developed to diagnose and predict fibrosis in CHB/NAFLD. Treatment guidelines are not clear.

Insulin resistance exhibits varied metabolic abnormalities in nonalcoholic fatty liver disease, chronic hepatitis B and the combination of the two: a cross-sectional study

BACKGROUND

Insulin resistance (IR) related metabolic disorders are associated with a worse prognosis of chronic hepatitis B virus (CHB) infection or nonalcoholic fatty liver disease (NAFLD). However, the relationships among CHB, steatosis, IR and metabolic factors remain controversial. The study aims to evaluate the impact of insulin resistance severity on metabolic profiles in patients with CHB, NAFLD and the coincidence of the two.

METHODS

We conducted a cross-sectional study between January 2011 and December 2018 that included 2768 consecutive Chinese subjects (healthy controls: 667, CHB: 970, NAFLD: 878, CHB with NAFLD: 253). IR was determined with the homeostasis model assessment for insulin resistance (HOMA-IR). Metabolic measures included fasting serum insulin, glucose, lipid profiles and uric acid.

RESULTS

The prevalence of IR was increased in CHB with NAFLD subjects compared with that in control subjects or subjects with CHB or NAFLD alone (41.5% vs 2.9%/11.9%/36.9%, respectively; P < 0.001). Within NAFLD and CHB with NAFLD group, the frequency of metabolic syndrome, hypertension and hyperuricemia increased as the HOMA-IR category increased (P for trend < 0.05). A higher risk for total cholesterol, low-density lipoprotein cholesterol and elevated alanine transaminase was observed with IR in the CHB with NAFLD group compared with that in the other groups, while no stepwise increase in hypertriglyceridemia was found in HOMA-IR in the CHB with NAFLD group.

CONCLUSION

Insulin resistance is highly prevalent in patients with CHB combined with NAFLD, and the increased metabolic risk, rather than hypertriglyceridemia, is driven by IR in CHB combined with NAFLD.

Association between chronic hepatitis B infection and metabolic syndrome

PURPOSE

The association between chronic hepatitis B (CHB) infection and metabolic syndrome (MetS) remains inconclusive. This study was designed to determine the association between CHB infection and MetS among the US population with updated data and adjustments for a comprehensive set of risk factors.

METHODS

Adults aged 18 years or older who were clinically assessed for Hepatitis B and MetS from the National Health and Nutrition Examination Survey (NHANES) 2003-2004, 2005-2006, 2007-2008, 2009-2010, 2011-2012, and 2013-2014 cycles were included in the study (N = 53,392,666). MetS was defined according to the NCEP/ATP III guideline. CHB was identified by the seropositivity of Hepatitis B surface antigen and core antibody in the absence of Hepatitis B surface antibody. Rao-Scott χ 2test and logistic regressions were employed in the analyses.

RESULTS

MetS was less prevalent among adults with CHB compared to adults without CHB (12.1% vs. 18.8%, p = 0.073). In adjusted analyses, adults with CHB were 48% less likely to have MetS compared to those without CHB (95% Confidence Interval [CI]: 0.29-0.94). Regarding individual component of MetS, CHB was inversely associated with high waist circumference (AOR = 0.32, 95% CI: 0.21-0.49) and hypoalphalipoproteinemia (AOR = 0.48, 95% CI: 0.25-0.91). No association between CHB and other metabolic components were found.

CONCLUSIONS

CHB was inversely associated with MetS, high waist circumference, and hypoalphalipoproteinemia. No significant association was found between CHB and other MetS components.

Serum leptin and homeostasis model assessment-IR as novel predictors of early liver fibrosis in chronic hepatitis B virus infection

BACKGROUND

The relationship between hepatitis B virus (HBV) infection, leptin and insulin resistance remains unclear. We hypothesised links between serum leptin and insulin resistance in non-diabetic patients with chronic viral hepatitis B infection and their relation to liver fibrosis.

METHODS

We recruited 190 untreated patients with chronic HBV infection and 72 healthy controls. Serum leptin, fasting glucose, insulin, liver function tests (LFTs), C-peptide and Homeostasis model assessment-IR (HOMA-IR) were measured/calculated by ELISA and standard techniques.

RESULTS

Serum leptin, C-peptide (both P < 0.001), HOMA-IR (P = 0.021) and several LFTs were increased in patients with chronic HBV-infection. In multivariate regression analysis, both HOMA-IR (P = 0.003) and leptin (P = 0.002) were significant independent predictors of HBV infection. There were significant positive correlations (P < 0.01) between leptin and HOMA-IR (r = 0.81), between serum leptin and METAVIR activity (r = 0.95), and between HOMA-IR and BMI (r = 0.75), fasting glucose (r = 0.005), and fasting insulin (r = 0.81). Several LFTs, glucose and insulin correlated modestly (r = 0.61-0.69, P < 0.05) with leptin.

CONCLUSION

Serum leptin may be related to the rate of fibrosis progression in nondiabetic patients with chronic HBV infection. Follow-up by serial measurement of serum leptin and HOMA-IR in non diabetic HBV-infected patients may be used as a non-invasive marker of early liver fibrosis.

Effect of hepatitis B virus on steatosis in hepatitis C virus co-infected subjects: A multi-centre study and systematic review

It remains unclear whether hepatitis B virus (HBV) infection may modify the severity of viral steatosis in patients coinfected with chronic hepatitis C virus (HCV). We examined the influence of coinfection with HBV on prevalence of steatosis in chronic hepatitis C in a multi-centre cohort of HBV-HCV subjects, and by performing a systematic review and meta-analysis of the literature. We centrally and blindly assessed steatosis prevalence and severity in a cohort of HBV-HCV coinfected subjects compared to HCV and HBV monoinfected controls and we performed a systematic review of studies addressing the prevalence of steatosis in HBV-HCV subjects compared to HCV controls. In the clinical cohort, we included 85 HBV-HCV, 69 HBV and 112 HCV subjects from 16 international centres. There was no significant difference in steatosis prevalence between the HBV-HCV and the HCV groups (33% vs 45%, P = .11). In subgroup analysis, lean HBV-HCV subjects with detectable HBV DNA had less steatosis than lean HCV subjects matched for HCV viremia (15% vs 45%, P = .02). Our literature search identified 5 additional studies included in a systematic review. Overall, prevalence of steatosis > 5% was similar in HBV-HCV infection compared to HCV (pooled odds ratio [OR] 0.91, 95% CI 0.53-1.6) although there was significant heterogeneity (I² 69%, P = .007). In conclusion, although the prevalence of steatosis is similar in HBV-HCV compared to HCV subjects, our analysis suggests that there may be an inhibitory effect of HCV-induced steatogenesis by HBV in certain subgroups of patients.

Insulin Resistance and Metabolic Syndrome: Clinical and Laboratory Associations in African Americans Without Diabetes in the Hemochromatosis and Iron Overload Screening Study

BACKGROUND

We sought to determine associations with insulin resistance (IR) and metabolic syndrome (MetS) in African Americans.

METHODS

We studied African American adults without diabetes in a postscreening examination. Participants included Cases: transferrin saturation (TS) >50% and serum ferritin (SF) >300 μg/L (M), and TS >45% and SF >200 μg/L (F), regardless of HFE genotype; and Controls: TS/SF 25th to 75th percentiles and HFE wt/wt (wild type). We excluded participants with fasting <8 h; fasting glucose >126 mg/dL; hepatitis B or C; cirrhosis; pregnancy; or incomplete datasets. We analyzed age; sex; Case/Control; body mass index (BMI); systolic and diastolic blood pressures; neutrophils; lymphocytes; alanine aminotransferase; aspartate aminotransferase; elevated C-reactive protein (CRP >0.5 mg/L); TS; and SF. We computed homeostasis model assessment of insulin resistance (HOMA-IR) using fasting serum glucose and insulin, and defined IR as HOMA-IR fourth quartile (≥2.42).

RESULTS

There were 312 Cases and 86 Controls (56.3% men). Ninety-one percent had HFE wt/wt. None had HFE p.C282Y. A significant increasing trend across HOMA-IR quartiles was observed for BMI only. Multivariable regression on HOMA-IR revealed significant positive associations: age; BMI; lymphocytes; SF; and CRP >0.5 mg/L; and significant negative associations: neutrophils and TS. Logistic regression on IR revealed BMI [odds ratio (OR) 1.3 (95% confidence interval 1.2-1.4)] and CRP >0.5 mg/L [OR 2.7 (1.2-6.3)]. Fourteen participants (3.5%) had MetS. Logistic regression on MetS revealed one association: IR [OR 7.4 (2.1-25.2)].

CONCLUSIONS

In African Americans without diabetes, IR was associated with BMI and CRP >0.5 mg/L, after adjustment for other variables. MetS was associated with IR alone.

Unawareness of Hepatitis B Virus Infection confers on Higher Rate of Metabolic Syndrome: A Community-based Study

The objective of this study was to determine whether awareness of hepatitis B virus (HBV) serostatus was discordant with metabolic syndrome (MetS) among people with chronic HBV infection. We conducted a community-based study in four Taiwanese districts. A total of 3493 adult participants were recruited. Participants who were hepatitis B surface antigen (HBsAg) seropositive and had self-reported HBV infection were considered aware of hepatitis B (aHB); those who denied a history of HBV infection were considered unaware of hepatitis B (uaHB). Among the 454 participants who were HBsAg seropositive, 275 (60.6%) were aHB and 179 (39.3%) were uaHB. Hypertriglyceridemia showed significant inverse association with HBsAg seropositive, especially among those who were aHB. Insulin resistance was significantly, positively associated with HBsAg seropositive, especially among participants who were uaHB. Those who were uaHB had a higher risk of central obesity, hyperglycemia, insulin resistance, and MetS than those who were aHB (odds ratio = 2.33, 1.64, 2.15, 1.85, respectively, all p < 0.05). The association among the prevalence of MetS, its individual components and HBsAg seropositivity varies according to awareness of HBV infection. It is important to recognize an individual's risk for MetS, especially who were unaware of HBV infection.

Serum HBV surface antigen positivity is associated with low prevalence of metabolic syndrome: A meta-analysis

Background and aim

As there is conflicting evidence for the relationship between hepatitis B virus surface antigen (HBsAg) positivity and the prevalence of metabolic syndrome (MetS), we performed a meta-analysis to investigate whether HBsAg positivity affects the incidence of MetS.

Methods

Observational studies on the relationship between HBsAg positivity and MetS were obtained from PubMed, Web of Science, and the Cochrane Library in April 2016. The pooled odds ratios (ORs) of MetS and its components (central obesity, increased fasting glucose, increased blood pressure, dyslipidemia) for subjects with or without HBsAg positivity were synthesized. The standardized mean difference of MetS components between HBsAg-positive participants and healthy controls was calculated. Heterogeneity was explored with subgroup analysis and sensitivity analysis. Publication bias was detected using Egger’s test and Begg’s test.

Results

Thirty studies were eligible for meta-analysis. The MetS OR for HBsAg-positive participants was significantly decreased compared with the controls [OR = 0.80, 95% confidence interval (CI), 0.70–0.90]. The negative effect of HBsAg positivity on elevated triglycerides (OR = 0.62, 95% CI, 0.59–0.64) was strong, while that for increased fasting blood glucose was weak (OR = 0.94, 95% CI, 0.90–0.98). The pooled ORs of central obesity (OR = 0.97, 95% CI, 0.91–1.04), reduced high-density lipoprotein cholesterol (OR = 0.98, 95% CI, 0.83–1.14), and elevated blood pressure (OR = 1.00, 95% CI, 0.80–1.25) for HBsAg-positive participants were all not significantly different compared with the controls. No publication bias was detected.

Conclusions

Serum HBsAg positivity is inversely associated with the prevalence of MetS. Among the five components of MetS, elevated triglycerides had the strongest inverse relationship with HBsAg positivity.

Chronic hepatitis B virus infection status is more prevalent in patients with type 2 diabetes

Aims/Introduction

It has not been reported whether chronic hepatitis B virus infection (CHB) is associated with a specific type of diabetes. We sought to investigate the prevalence of CHB status in different diabetes subtypes among a Chinese population.

Materials and Methods

This was a cross‐sectional study. A total of 381 patients with adult‐onset autoimmune diabetes, 1,365 patients with type 2 diabetes and 1,365 non‐diabetic controls were recruited from June 2005 to February 2014. The exclusion criteria included: (i) hepatitis C virus antibody positive; (ii) hepatic cirrhosis; and (iii) malignant neoplasm and severe renal dysfunction (serum creatinine >450 μmol/L). Patients were grouped as hepatitis B virus‐negative and CHB status.

Results

Patients with type 2 diabetes had a higher prevalence of CHB than the controls in the overall population (13.5 vs 10.0%, P = 0.004) and among patients with normal hepatic function (13.3 vs 8.8%, P = 0.002). There was no difference in the prevalence of CHB status between patients with adult‐onset autoimmune diabetes and the controls. Multiple logistic regression analysis showed that the odds ratio of CHB increased by ~1.5‐fold in patients with type 2 diabetes than in the control group after adjustment for age, sex and body mass index, regardless of hepatic function status.

Conclusions

CHB status was more prevalent in patients with type 2 diabetes than in individuals with adult‐onset autoimmune diabetes and the controls among the Chinese population. Further research is required to ascertain whether CHB status increases the risk of developing type 2 diabetes, or whether type 2 diabetes, but not adult‐onset autoimmune diabetes, increases the risk of CHB.

Influence of hepatic steatosis on chronic hepatitis B

Worldwide, nonalcoholic fatty liver disease (NAFLD) has a high prevalence with the rising rates of overweight and/or obesity. Chronic hepatitis B (CHB) virus infection is another common cause of infectious liver diseases. In practice, the overlap between NAFLD and CHB is rather common. In this review, we summarize the relationship between NAFLD and CHB, the influence of NAFLD on CHB, and the role of the metabolic syndrome in the development of hepatic fibrosis, cirrhosis and hepatocellular carcinoma. Recent advances in understanding the reason CHB is prone to overlap NAFLD will be discussed. The adverse effects caused by NAFLD on the treatment and progression of CHB will be also elucidated. NAFLD overlapping CHB often raises a great challenge to the clinicians, in terms of diagnosis or treatment. Therefore, appropriate management of this complex situation is needed.

Relationship between chronic hepatitis B and metabolic syndrome: A structural equation modeling approach

OBJECTIVE

Investigate the nature of the relationship between chronic hepatitis B virus (HBV) infection and metabolic syndrome among nondiabetic adults.

METHODS

This was a cross-sectional analysis of 17,030 nondiabetic adults (7437 males and 9593 females; mean age, 36.0 ± 3.9 years) in northern Taiwan from 2008 to 2009. The associations of hepatitis B surface antigen (HBsAg) seropositivity with metabolic syndrome and cardio-metabolic parameters were assessed. A structural equation model was constructed to elucidate the pathways between chronic HBV infection and individual cardiometabolic risk factors.

RESULTS

A total of 2982 (17.5%) participants were HBsAg-seropositive. Of the seropositive and seronegative subjects, 15.5 and 16.9% had metabolic syndrome, respectively. The HBsAg-seropositive subjects had a lower odds of having metabolic syndrome compared with the seronegative subjects irrespective of gender and age (OR: 0.76, 95% CI: 0.68-0.85). The inverse associations remained significant after adjusting for body mass index and serum alanine aminotransferase levels. HBsAg seropositivity was inversely associated with hypertriglyceridemia (OR: 0.59, 95% CI: 0.52-0.66), and low serum levels of high-density lipoprotein cholesterol (OR: 0.86, 95% CI: 0.79-0.93) after adjustments. The structural equation model revealed chronic HBV infection had a significant negative effect on dyslipidemia both in males (B = -0.054) and females (B = -0.064).

CONCLUSIONS

The inverse relationship between chronic HBV infection and metabolic syndrome may be attributable to the net beneficial effects on lipid profiles.

Association between hepatitis B and metabolic syndrome: Current state of the art

Chronic hepatitis B (CHB) is a global health issue that increases the risk of liver cirrhosis and hepatocellular carcinoma in infected patients. Metabolic syndrome (MetS) is a disease endemic mostly to the developed countries. It is associated with high cardiovascular mortality and morbidity, diabetes mellitus as well as cancer. In this manuscript, we systematically review the published data on the relationship between MetS and CHB infection. Multiple studies have described highly variable correlations between CHB on one hand and MetS, non-alcoholic fatty liver disease and dyslipidemia on the other. No association between CHB and diabetes mellitus or atherosclerosis has been described as of now. The presence of MetS in patients infected with hepatitis B virus increases the risk of fibrosis, cirrhosis and hepatocellular carcinoma. Appropriate lifestyle, but also pharmacological interventions are needed to prevent the development of these complications.

Association between hepatitis B and metabolic syndrome: Current state of the art

Chronic hepatitis B (CHB) is a global health issue that increases the risk of liver cirrhosis and hepatocellular carcinoma in infected patients. Metabolic syndrome (MetS) is a disease endemic mostly to the developed countries. It is associated with high cardiovascular mortality and morbidity, diabetes mellitus as well as cancer. In this manuscript, we systematically review the published data on the relationship between MetS and CHB infection. Multiple studies have described highly variable correlations between CHB on one hand and MetS, non-alcoholic fatty liver disease and dyslipidemia on the other. No association between CHB and diabetes mellitus or atherosclerosis has been described as of now. The presence of MetS in patients infected with hepatitis B virus increases the risk of fibrosis, cirrhosis and hepatocellular carcinoma. Appropriate lifestyle, but also pharmacological interventions are needed to prevent the development of these complications.

HBV-related chronic liver disease and insulin resistance

The liver is the major organ regulating glucose metabolism. When liver injury occurs, glucose metabolism disturbance and insulin resistance (IR) may develop, which can even cause the development of hepatogenic diabetes. The correlation between viral hepatitis, liver cirrhosis and diabetes has become a hot research topic in recent years. This paper reviews the progress in research of hepatitis B virus (HBV) infection and early predictors of diabetes. We give a brief introduction to the concept of IR and its causes, and discuss the relationship of HBV infection, HBV and HCV coinfection, and hepatitis associated cirrhosis with IR. We also describe the possible mechanisms for IR in HBV infected people. Besides, we discuss the impact of IR on prognosis of HBV related chronic liver diseases, mainly fatty, liver fibrosis, and liver cancer. The clinical treatment of patients with HBV infection and IR is also discussed.

Systematic review: Preventive and therapeutic applications of metformin in liver disease

Metformin, a biguanide derivative, is the most commonly prescribed medication in the treatment of type 2 diabetes mellitus. More recently, the use of metformin has shown potential as a preventive and therapeutic agent for a broad spectrum of conditions, including liver disease and hepatic malignancies. In this systematic review, we critically analyze the literature behind the potential use of metformin across the spectrum of liver disease and malignancies. The PubMed and Ovid MEDLINE databases were searched from 2000 to March 2015, using a combination of relevant text words and MeSH terms: metformin and mammalian target of rapamycin, hepatitis B virus (HBV), hepatitis B virus (HCV), non-alcoholic fatty liver disease (NAFLD), hepatocellular carcinoma (HCC) or cholangiocarcinoma. The search results were evaluated for pertinence to the issue of metformin in liver disease as well as for quality of study design. Metformin has a number of biochemical effects that would suggest a benefit in treating chronic liver diseases, particularly in the context of insulin resistance and inflammation. However, the literature thus far does not support any independent therapeutic role in NAFLD or HCV. Nonetheless, there is Level III evidence for a chemopreventive role in patients with diabetes and chronic liver disease, with decreased incidence of HCC and cholangiocarcinoma. The use of metformin seems to be safe in patients with cirrhosis, and provides a survival benefit. Once hepatic malignancies are already established, metformin does not offer any therapeutic potential. In conclusion, there is insufficient evidence to recommend use of metformin in the adjunctive treatment of chronic liver diseases, including NAFLD and HCV. However, there is good evidence for a chemopreventive role against HCC among patients with diabetes and chronic liver disease, and metformin should be continued in patients even with cirrhosis to provide this benefit.

Identifying patients with chronic hepatitis B at high risk of type 2 diabetes mellitus: a cross-sectional study with pair-matched controls

BACKGROUND

The presence of diabetes mellitus (DM) is associated with increased liver morbidity and mortality risk in patients with chronic hepatitis B (CHB). Aim of this study was to identify factors associated with type 2 diabetes mellitus (T2DM) in CHB patients.

METHODS

A cross-sectional study with pair-matched controls was conducted in Nantong Third People's Hospital, Nantong University, China. From January 2008 to December 2012, a total of 1783 CHB patients were screened for study subjects, among whom 207 patients with T2DM were enrolled as cases and 207 sex- and age-matched non-DM patients as controls. Demographic, anthropometric, lifestyle, clinical, and laboratory data were obtained from each subject.

RESULTS

In the univariate model, thirteen variables showed marked differences between the DM group and non-DM group. Patients with longer duration of CHB (≥15 years) and alcoholic steatosis showed the highest likelihood of T2DM (odds ratio = 5.39 and 4.95; 95% confidence intervals 2.76-10.53 and 1.65-14.91). In the multivariate adjusted analysis, three CHB-related factors, namely high viral load, long duration of illness, and presence of cirrhosis, contributed to substantially increase the likelihood of T2DM, in addition to the other five risk factors including family history of DM, low education level, elevated triglycerides (TG), gamma-glutamyl transferase (GGT) levels, and presence of alcoholic steatosis.

CONCLUSIONS

Our findings suggest that high viral load, long duration of CHB, presence of cirrhosis, alcoholic steatosis and several other factors may be potential risk factors for development of T2DM in CHB patients. It is of vital importance to monitor glucose in high-risk CHB patients and aggressively intervene on modifiable risk factors.

Hepatitis B virus infection and metabolic syndrome: fact or fiction?

Although hepatitis C virus infection is known to be linked with insulin resistance, dyslipidemia, and hepatic steatosis, the relationship between hepatitis B virus (HBV) infection and metabolic factors remains unclear. HBV infection is a health problem worldwide, especially in endemic regions such as Asia and Africa. It induces liver decompensation, cirrhosis, hepatocellualr carcinoma, and premature mortality. The prevalence of metabolic syndrome continues to increase in parallel with the epidemic of obesity, which is closely associated with the development of diabetes, cardiovascular disease, or even cancer. The systemic review shows that chronic HBV infection protects against instead of promotes fatty liver. The mechanism is possibly due to a lower frequency of dyslipidemia profile in patients with chronic HBV infection. The association of HBV with metabolic syndrome, insulin resistance, and the risk of arteriosclerosis is still inconclusive. In addition, obesity, diabetes, and metabolic syndrome may accelerate the progression of liver disease in patients with chronic HBV infection and synergistically induce cirrhosis or even hepatocellualr carcinoma development.

A meta-analysis of the association between gestational diabetes mellitus and chronic hepatitis B infection during pregnancy

BACKGROUND

Chronic hepatitis B (CHB) infection during pregnancy is associated with insulin resistance. A meta-analytic technique was used to quantify the evidence of an association between CHB infection and the risk of gestational diabetes (GDM) among pregnant women.

METHODS

We searched PubMed for studies up to September 5th 2013. Additional studies were obtained from other sources. We selected studies using a cohort-study design and reported a quantitative association between CHB infection during pregnancy and risk of GDM. A total of 280 articles were identified, of which fourteen publications involving 439,514 subjects met the inclusion criteria. A sequential algorithm was used to reduce between-study heterogeneity, and further meta-analysis was conducted using a random-effects model.

RESULTS

Ten out of the fourteen studies were highly homogeneous, indicating an association of 1.11 [the adjusted odds ratio, 95% confidence interval 0.96-1.28] between CHB infection during pregnancy and the risk of developing GDM. The heterogeneity of the additional four studies may be due to selection bias or possible aetiological differences for special subsets of pregnant women.

CONCLUSIONS

These results indicate that CHB infection during pregnancy is not associated with an increased risk of developing GDM among pregnant women except those from Iran.