Smoking and liver cancer in China: case-control comparison of 36,000 liver cancer deaths vs. 17,000 cirrhosis deaths

A Systematic Review of the Effects of Smoking on the Cardiovascular System and General Health

The main risk factor for atherosclerotic cardiovascular disease is smoking. Nicotine and carbon monoxide are two dangerous substances that are found in cigarette smoke. The increased heart rate can have an almost instantaneous impact on the heart and blood vessels. Smoking is well known to cause oxidative stress, endanger the lining of the arteries, and accelerate the accumulation of fatty plaque in the blood vessels. It raises the danger of sudden thrombotic events, inflammatory alterations, and low-density lipoprotein oxidation. The smoke's carbon monoxide decreases the blood's capacity to deliver oxygen, adding to the heart's stress. Notably, these risks increase when diabetes, hypertension, high cholesterol, and glucose intolerance are present. It has a detrimental effect on peripheral blood vessels, raising the possibility of thromboangiitis obliterans. Stroke risk is known to be increased by smoking. As compared to those who continue to smoke, those who give up smoking have a much longer life expectancy. Chronic cigarette smoking has been shown to affect the macrophages' ability to remove cholesterol. Abstinence from smoking enhances the function of high-density lipoproteins and cholesterol efflux, lowering the risk of plaque buildup. In this review, we present the most recent information regarding the causal relationship between smoking and cardiovascular health as well as the long-term advantages of quitting.

Urban and Rural Disparities in a WeChat-Based Smoking Cessation Intervention among Chinese Smokers

INTRODUCTION

Tobacco use, which is directly responsible for 10% of total deaths per year globally, remains consistently high, with approximately 20% of the population reporting regular consumption globally. Moreover, health disparities regarding tobacco consumption and smoking cessation are growing between rural and urban populations worldwide. Social media interventions for tobacco cessation may effectively reach both groups. The objective of this study was to evaluate the efficacy of a WeChat-delivered smoking cessation intervention among rural and urban Chinese smokers, and to assess moderating variables that may contribute to differential intervention efficacy.

METHODS

WeChat was used to recruit smokers into this intervention study between 1 July and 5 August 2019. Participants were randomized to one of three intervention schedules: participants in the Standard Group and the Enhanced Group received 20 smoking-related messages over 2 weeks, whereas participants in the Enhanced Group received an extra 6 oral health-related messages for one week. Participants in the control group received 20 smoking-related messages after the post-intervention assessment. Participants completed questionnaires at baseline and at 4 weeks follow-up. Our primary outcome was smoking cessation stage of change and secondary outcome was 24-h point prevalence abstinence (PPA). Urban and rural areas were based on self-reported living areas. Chi-squared test, Fisher's exact test, ANOVA test, linear regression, and logistic regression were used for analysis.

RESULTS

Overall, 403 participants completed the intervention (233 rural, 107 suburban, 63 urban). Compared to urban participants, rural participants were more likely to have progressed to a later stage of change (β = 0.40, 95% CI: 0.13, 0.67) and to report higher 24-h PPA rates at follow-up (aOR = 3.23, 95% CI: 1.36, 7.68). After stratification by living area, the intervention effects in stage of change and 24-h PPA rate at follow-up were only found in the urban subgroup.

DISCUSSION

Smokers who lived in rural areas reported better smoking cessation outcomes compared with urban smokers; however, the efficacy of a WeChat-based smoking cessation intervention was only found for participants living in an urban area. WeChat based smoking cessation interventions should be used to promote smoking cessation in urban, suburban, and rural areas.

Pretreatment age and serum lactate dehydrogenase as predictors of synchronous second primary cancer in patients with nasopharyngeal carcinoma

OBJECTIVES

Nasopharyngeal carcinoma (NPC) is a common cancer and is treated primarily by chemotherapy and radiotherapy. However, NPC with synchronous second primary cancer (SSPC) is very rare and its risk factors, treatment and prognosis remain unclear. In this study, we aimed to analyze patients with NPC and SSPC, and attempt to find potential predictors for these patients.

MATERIALS AND METHODS

We retrospectively collected 681 patients with NPC from 2006 to 2018. Patients in this study were divided into two groups: those patients with SSPC and those without SSPC. We then analyzed the demographic data and survival of these two groups. Independent predictors of SSPC were determined by multivariate regression analysis. A comprehensive review of the literature was also performed.

RESULTS

We identified 17 NPC patients with SSPC in our case series and 13 cases in the literatures, and the most common SSPC is lung (16.1%). In univariate analysis, NPC patients with SSPC had older age (P < 0.001) and higher serum lactate dehydrogenase (LDH) (P = 0.008), compared with those without SSPC. In multivariate analysis, old age (P = 0.001) and high serum LDH (P = 0.023) remained independent predictors of SSPC, and a predictive equation model was established. NPC patients with SSPC had a significantly lower 5-year disease-specific survival rate compared with patients without SSPC (34.0% vs. 77.6%, P < 0.001) CONCLUSION: This study demonstrated that pretreatment age and serum LDH were independent predictors for SSPC in NPC patients. These independent factors can be used for early detection, and better facilitate the design of more appropriate treatment by medical professionals.

Nicotine Promotes WRL68 Cells Proliferation Due to the Mutant p53 Gain-of-Function by Activating CDK6-p53-RS-PIN1-STAT1 Signaling Pathway

The liver is an important organ with many tasks, such as dealing with drugs, alcohol and other toxins to remove them from the body. Nicotine is the more abundant component in cigarette smoking, which is first metabolized in liver and increases the risk of developing hepatocellular carcinoma (HCC). Also, genotoxic potential of nicotine has been extensively studied in vitro. However, the carcinogenic action of nicotine on the HCC needs to be elucidated. The current study demonstrated that chronic exposure to nicotine significantly promotes human normal fetal hepatic cell line (WRL68 cells) proliferation in a time- and concentration-dependent manner resulting from G0/G1-S-phase transition. Also remarkably, nicotine induced the level of p53 mutation at Ser249 (p53-RS). Note as well that the level of STAT1 protein was increased along with p53-RS owing to the prolonged half-life of STAT1. Furthermore, it is suggested that CDK6-dependent binding between phosphorylation of p53-RS at Ser249 and PIN1 by nicotine treatment leads to the nucleus translocation, followed by interacting with STAT1 and subsequent activation of STAT1 via the improvement of its stability, which is involved in cellular growth and colony formation after nicotine treatment. Simply put, these findings indicated that nicotine induces mutant p53 gain-of function (GOF), activating CDK6-p53-RS-PIN1-STAT1 signaling pathway and promoting cell proliferation, which could contribute to HCC for smokers.

Solid fuels for cooking and tobacco use and risk of major chronic liver disease mortality: a prospective cohort study of 0.5 million Chinese adults

BACKGROUND

Harmful substances in solid fuel and tobacco smoke are believed to enter the bloodstream via inhalation and to be metabolized in the liver, leading to chronic liver damage. However, little is known about the independent and joint effects of solid fuel use and smoking on risks of chronic liver disease (CLD) mortality.

METHODS

During 2004-08, ∼0.5 million adults aged 30-79 years were recruited from 10 areas across China. During a 10-year median follow-up, 2461 CLD deaths were recorded. Multivariable Cox regression yielded adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for the individual associations of self-reported long-term cooking fuel and tobacco use with major CLD death.

RESULTS

Overall, 49% reported solid fuel use and 26% smoked regularly. Long-term solid fuel use for cooking and current smoking were associated with higher risks of CLD deaths, with adjusted HRs of 1.26 (95% CI, 1.02-1.56) and 1.28 (1.13-1.44), respectively. Compared with never-smoking clean fuel users, the HRs were 1.41 (1.10-1.82) in never-smoking solid fuel users, 1.55 (1.17-2.06) in regular-smoking clean fuel users and 1.71 (1.32-2.20) in regular-smoking solid fuels users. Individuals who had switched from solid to clean fuels (1.07, 0.90-1.29; for median 14 years) and ex-regular smokers who stopped for non-medical reasons (1.16, 0.95-1.43; for median 10 years) had no evidence of excess risk of CLD deaths compared with clean fuel users and never-regular smokers, respectively.

CONCLUSIONS

Among Chinese adults, long-term solid fuel use for cooking and smoking were each independently associated with higher risks of CLD deaths. Individuals who had stopped using solid fuels or smoking had lower risks.

Extended Analysis and Evidence Integration of Chloroprene as a Human Carcinogen

β-Chloroprene is used in the production of polychloroprene, a synthetic rubber. In 2010, Environmental Protection Agency (EPA) published the Integrated Risk Information System "Toxicological Review of Chloroprene," concluding that chloroprene was "likely to be carcinogenic to humans." This was based on findings from a 1998 National Toxicology Program (NTP) study showing multiple tumors within and across animal species; results from occupational epidemiological studies; a proposed mutagenic mode of action; and structural similarities with 1,3-butadiene and vinyl chloride. Using mouse data from the NTP study and assuming a mutagenic mode of action, EPA calculated an inhalation unit risk (IUR) for chloroprene of 5 × 10^-4 per µg/m³ . This is among the highest IURs for chemicals classified by IARC or EPA as known or probable human carcinogens and orders of magnitude higher than the IURs for carcinogens such as vinyl chloride, benzene, and 1,3-butadiene. Due to differences in pharmacokinetics, mice appear to be uniquely responsive to chloroprene exposure compared to other animals, including humans, which is consistent with the lack of evidence of carcinogenicity in robust occupational epidemiological studies. We evaluated and integrated all lines of evidence for chloroprene carcinogenicity to assess whether the 2010 EPA IUR could be scientifically substantiated. Due to clear interspecies differences in carcinogenic response to chloroprene, we applied a physiologically based pharmacokinetic model for chloroprene to calculate a species-specific internal dose (amount metabolized/gram of lung tissue) and derived an IUR that is over 100-fold lower than the 2010 EPA IUR. Therefore, we recommend that EPA's IUR be updated.

The Incidence of Hepatocellular Carcinoma in Iran from 1996 to 2016: a Systematic Review and Meta-analysis

PURPOSE

Hepatocellular carcinoma or liver cancer (LC) is one of most important cancer around the world. There are several reports about LC incidence from various Iranian locations with conflicting results. The present study aimed to accomplish a systematic review to estimate the accurate incidence rate of LC among Iranian people.

METHODS

This systematic review was performed based on the preferred reporting items for systematic reviews and meta-analyses (PRISMA) checklist in 2018. A literature search was conducted using international databases (Medline/PubMed, Scopus, ScienceDirect, and Google Scholar) for English papers and national databases (Scientific Information Database, MagIran, IranMedex, and IranDoc) for Persian papers which estimated incidence rate of LC in any geographical area of Iran. The incidence rate of LC was calculated using random effect model.

RESULTS

Of 171 papers in the primary searches, 15 studies were included by advanced screening and refinement. The age-standardized rate (ASR) of LC was 1.66 (95% CI 1.49-1.83) for males and 1.25 (95% CI 1.12-1.38) for females.

CONCLUSIONS

The incidence rate of LC in Iran was lower in comparison to other countries. Afterwards, more studies are necessary to outline the accurate incidence rate and the trend of LC among Iranian population.

Advancing Age and Comorbidity in a US Insured Population-Based Cohort of Patients With Chronic Hepatitis B

Chronic hepatitis B (CHB) comorbidity data are limited. Using insurance claims databases, our aims were to determine the prevalence and incidence of nonliver comorbidities in CHB patients over time and the predictors of select comorbidities in CHB patients. Patients were adults with continuous coverage (commercial/Medicare or Medicaid) 6 months prior to and after the first CHB diagnosis and matched non-CHB patients. Deyo-Charlson Comorbidity Index (DCCI) and comorbidities were analyzed (cardiovascular disease [CVD], carcinoma, diabetes mellitus [DM], obesity, hypertension [HTN], hyperlipidemia, alcohol use, renal impairment, chronic kidney disease [CKD], and osteoporosis/fracture [OF]). The study population included 44,026 CHB cases and 121,568 matched controls. CHB patient mean age increased from 48.1 ± 11.9 years in 2006 to 51.8 ± 12.4 years in 2015 for commercial/Medicare and from 44.1 ± 11.1 years to 50.2 ± 10.2 years for Medicaid (P < 0.001 for both). The Medicaid CHB cohort was the sickest (DCCI, 2.6, P < 0.001). The commercial/Medicare 2006 CKD prevalence rate was 36.1/1,000 in CHB patients and 10.2/1,000 in controls, increasing to 97.6 and 38.8 in 2015, respectively. The 2006 CKD incidence (per 1,000 person-years) was 10.3 and 4.8 and 15.2 and 11.3 by 2015, respectively (P < 0.05 for all). The strongest predictors for CKD were DM (hazard ratio [HR], 2.48), HTN (HR, 3.29), and CVD (HR, 2.61) (all P < 0.0001). Similar prevalence and incidence changes were observed for OF. The strongest predictors for OF were female gender (HR, 2.22), alcohol use (HR, 2.02), and viral coinfection (HR, 1.37) (all P < 0.0001). Conclusion: Insured CHB patients were older, had more comorbidities, and experienced higher incidence and prevalence of CKD and OF than controls.

Hepatocellular Carcinoma in Asia: A Challenging Situation

Amongst the primary tumors of the liver, hepatocellular carcinoma (HCC) is the most common. It is also one of the most prevalent types of cancers in Asia. Mostly, HCC occurs on a background of chronic liver disease and liver cirrhosis; however, de novo HCCs can also arise in apparently normal looking livers on imaging. There are multiple risk factors for HCC, including hepatitis B and C infections, diabetes mellitus, alcohol, and nonalcoholic steatohepatitis. Other common risk factors which are known to be involved in the pathogenesis of HCC are obesity, food contaminated with aflatoxin and hemochromatosis. Many of these factors are commonly found in this part of the world, hence the high burden of disease. Besides these, smoking and familial predisposition to HCC also seem to have an important role to play in its development. Majority of HCC are missed at an early stage despite the emphasis on adequate screening and surveillance strategies. Therefore, most of the time these tumors are diagnosed at a fairly advanced stage, when palliative treatment is the only therapeutic option left. Hence, prevention of HCC by controlling and minimizing the possible risk factors is the need of the hour. How to cite this article: Jafri W, Kamran M. Hepatocellular Carcinoma in Asia: A Challenging Situation. Euroasian J Hepatogastroenterol 2019; 9(1):27-33.

Association between cotinine-verified smoking status and risk of nonalcoholic fatty liver disease

BACKGROUND & AIMS

The relationship between cigarette smoking and nonalcoholic fatty liver disease (NAFLD) has been controversial. Most relevant studies have relied on self-reported questionnaires. We aimed to elucidate the association between smoking status and NAFLD using an objective biomarker of tobacco exposure (urinary cotinine) and self-reported questionnaire.

METHODS

A cross-sectional study was conducted on 160 862 asymptomatic examinees who underwent abdominal ultrasonography and urinary cotinine measurements between April 2011 and December 2015. Cotinine-verified current smokers were defined as participants with urinary cotinine levels ≥50 ng/mL.

RESULTS

The mean age of the study population was 36.1 years, and the proportion of men was 51.7%. The proportions of self-reported and cotinine-verified current smokers were 17.6% and 17.7% respectively. After adjusting for confounding factors, self-reported current smoking was associated with an increased risk of NAFLD (adjusted odds ratio [AOR], 1.10; 95% confidence interval [CI], 1.06-1.14). Moreover, among the current smokers, the risk of NAFLD increased with an increase in the amount of cigarette smoking (<10 and ≥10 pack-years vs never smokers; AOR, 1.04 and 1.11; 95% CI, 1.01-1.08 and 1.05-1.16 respectively). Cotinine-verified current smoking was also associated with an increased risk of NAFLD (AOR, 1.10; 95% CI, 1.06-1.14).

CONCLUSIONS

Cotinine-verified current smoking and self-reported current smoking were independent risk factors for NAFLD. Further longitudinal studies are needed to more clearly elucidate the impact of smoking on the development of NAFLD.

The trends and projections in the incidence and mortality of liver cancer in urban Shanghai: a population-based study from 1973 to 2020

Background

In 2012, liver cancer ranked as the fifth and eighth most common cancer in men and women, respectively, in urban Shanghai. This study aims to present the trend and projection of age-specific incidence and mortality of liver cancer in Shanghai.

Methods

We extracted data of liver cancer incident cases and deaths between 1973 and 2012. An age-period-cohort model was used to analyze the data.

Results

A total of 47,344 men and 18,692 women were diagnosed with liver cancer from 1973 to 2012. The overall age-standardized incidence was 26.89 and 8.89 per 100,000 for men and women, respectively. Correspondingly, a total of 44,355 and 18,084 men and women died from liver cancer during this period. The overall age-standardized death rate was 25.34 per 100,000 in men and 9.39 per 100,000 in women. Between 1973 and 2012, liver cancer incidence and mortality in all age groups, except people aged 0-19 years, experienced a significant decline. Similar temporal patterns were detected in liver cancer mortality in both sexes when compared with incidence. Liver cancer incidence and mortality are expected to further decline among all age groups in 2013-2020 in both sexes, though the numbers of incident cases will remain stable.

Conclusion

Incidence and mortality of liver cancer in urban Shanghai have decreased by about 40% and 50%, respectively, over the past four decades. This decline is expected to continue in the near future. However, the population is aging, which is reflected in the increasing crude rates and decreasing age-adjusted rates.

Association between smoking and non-alcoholic fatty liver disease: A systematic review and meta-analysis

Background/aims

Non-alcoholic fatty liver disease is one of the most common chronic liver diseases. Some risk factors are known to influence the development of non-alcoholic fatty liver disease, but the effect of tobacco smoking on the progression of non-alcoholic fatty liver disease is controversial. The main goal of this systematic review and meta-analysis is to investigate the association between smoking and non-alcoholic fatty liver disease.

Method

Electronic databases (PubMed, Scopus, and ISI Web of Science) were searched to find published articles on non-alcoholic fatty liver disease and smoking until December 2016. All relevant studies were screened by inclusion and exclusion criteria and compatible studies were chosen. The Newcastle-Ottawa Scale was used to assess the methodological quality of eligible articles. Subsequently, information was gathered based on the following: author, publication year, keywords, country, inclusion and exclusion criteria, main results, study design, conclusion, and confounder variables (age, body mass index, gender, ethnicity, and diabetes). Finally, analyses were performed using Comprehensive Meta-Analysis Software.

Results

Data were extracted from 20 observational studies (9 cross-sectional, 6 case-control, 4 cohort studies, and 1 retrospective cohort study). A significant association was observed between smoking and non-alcoholic fatty liver disease with a pooled odds ratio of 1.110 (95% confidence interval, 1.028-1.199), p-value = 0.008. The statistical heterogeneity was medium with an I2 of 40.012%, p-heterogeneity = 0.074. Also there was a significant relation between non-alcoholic fatty liver disease and passive smoking with a pooled odds ratio of 1.380 (95% confidence interval, 1.199-1.588; p-value = 0.001; I2 = 59.41; p-heterogeneity = 0.117).

Conclusion

Our meta-analysis demonstrated that smoking is significantly associated with non-alcoholic fatty liver disease. Further prospective studies exploring the underlying mechanisms of this association should be pursued. Also passive smoking increases the risk of non-alcoholic fatty liver disease about 1.38-fold. The effects of smoking cigarettes on active smokers (current smoker, former smoker, and total smoker) are less than passive smokers. Further studies are needed to compare the of effects of passive and active smoking on non-alcoholic fatty liver disease.

Effect of smoking on survival of patients with hepatocellular carcinoma

BACKGROUND & AIMS

Lifestyle factors such as smoking, obesity and physical activity have gained interest in the field of hepatocellular carcinoma. These factors play a significant role in the development of hepatocellular carcinoma. Several studies revealed the impact of tobacco consumption on the development of hepatocellular carcinoma and its synergistic effects with viral etiologies (hepatitis B and C). The effects of smoking on survival in patients with a diagnosed hepatocellular carcinoma have not yet been investigated in a Western cohort where hepatitis C infection is a major risk factor.

METHODS

Using data from a prospective cohort of patients with hepatocellular carcinoma who were followed at the University Hospital of Bern, Switzerland, survival was compared by Kaplan-Meier analysis in smokers and nonsmokers, and multivariate Cox regression was applied to control for confounding variables.

RESULTS

Of 238 eligible hepatocellular carcinoma patients, 64 were smokers at the time of inclusion and 174 were nonsmokers. Smokers had a significant worse overall survival than nonsmokers (hazard ratio 1.77, 95% confidence interval: 1.22-2.58, P=.003). Analysis of patients according to their underlying liver disease, revealed that smoking, and not nonsmoking, affected survival of hepatitis B virus and C virus-infected patients only. In this subgroup, smoking was an independent predictor for survival (hazard ratio 2.99, 95% confidence interval: 1.7-5.23, P<.001) and remained independently predictive when adjusted for confounding variables.

CONCLUSIONS

This study shows that smoking is an independent predictor of survival in hepatitis B virus/hepatitis C virus-infected patients with hepatocellular carcinoma.

Cigarette smoking as a risk factor for the development of and mortality from hepatocellular carcinoma: An updated systematic review of 81 epidemiological studies

BACKGROUND AND AIMS

Hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide and its incidence has increased during the past decade. While hepatitis B and C virus infections and alcohol were established risk factors, the impact of smoking on the incidence and mortality of HCC was needed to be confirmed.

METHODS

We reviewed cohort and case-control studies evaluating the association between cigarette smoking and incidence and mortality of HCC from MEDLINE and Google Scholar. We also checked reference lists of original studies and review articles manually for cross-references up to February 2016. We extracted the relevant information on participant characteristics and study outcomes, as well as information on the methodology of the studies. We also assessed the quality of the included trials using critical appraisal skills program checklists. Meta-analysis was performed by using RevMan 5.3 software.

RESULTS

A total of 81 studies were included in the systematic review. Pooled OR for HCC development with current smokers was 1.55 (95% CI: 1.46 to 1.65; P < 0.00001). Pooled OR for HCC development with former smokers was 1.39 (95% CI: 1.26 to 1.52; P < 0.00001) and pooled OR for HCC development with heavy smokers was 1.90 (95% CI: 1.68 to 2.14; P < 0.00001). Pooled OR for the mortality of current smokers with HCC was 1.29 (95% CI: 1.23 to 1.34; P < 0.00001); and for former smokers with HCC, it was 1.20 (95% CI: 1.00 to 1.42; P = 0.04).

CONCLUSIONS

Cigarette smoking increases the incidence and mortality of HCC. Further studies are needed to evaluate possible impact of quitting smoking on decreasing this risk.

Serum lipid profile as a marker of liver impairment in hepatitis B Cirrhosis patients

BACKGROUND

Chronic HBV infection is a major cause of Cirrhosis and an important risk factor to develop hepatocellular carcinoma. The study is conducted to find out the changes in the lipid metabolism of HBV-cirrhosis patients.

METHODS

In the present study, serum lipid profiles of patients with HBV-cirrhosis were assessed by utilizing micro-lab and gas chromatography, while risk factors for transmission of HBV-cirrhosis studied through the standard questionnaire.

RESULTS

The epidemiological and etiological risk factors strongly associated with HBV-cirrhosis patients compared to controls, included as family history, shave from the barber, blood transfusion (without proper screening), mutual sharing of household contents, positive surgery history, and dental treatment. The HBV-cirrhosis patients have significantly lower level (p < 0.001) of lipid profile including total cholesterol (96.65 mg/dl), TAG (82.85 mg/dl), VLDL-C (16.57 mg/dl), LDL-C (68.27 mg/dl), HDL-C (27 mg/dl) and total lipid (424.76 mg/dl) in comparison to controls, indicating hypolipidemia in patients. The MELD score indicated mild prognostic values of the hepatic function for the study group. The result of total fatty acid composition of HBV-cirrhotic patients with comparison of control subjects reveals that palmitic (24.54 g/100 g) and palmitoleic acid (4.65 g/100 g) were significantly (p < 0.05) higher whereas eicosatrienoic (0.09 g/100 g), arachidonic (3.57 g/100 g), linoleic (22.75 g/100 g) and α-linolenic acid (0.12 g/100 g) were significantly lower. Marker for stearoyl-CoA desaturase (SCD = ∆9-desaturase) activity i.e. palmitoleic: palmitic (0.2) and oleic: stearic acid (1.5) ratios, originated higher in HBV-cirrhotic patients, while PUFA: SFA (0.6) was lower in HBV-cirrhosis patients as compared with control subjects. The serum SFA and MUFA were increased while PUFA were reduced in both total and free form.

CONCLUSION

Present study concluded that hypolipidemia observed in HBV-cirrhosis patients, MELD were found to be independent predictors of survival and alteration in fatty acid composition, possibly due to impairment in fatty acid metabolism by enzymatic elongation and desaturation.

Management of the patient with SVR

In the current era of therapy with direct-acting antiviral (DAAs) drugs, achievement of a sustained virological response (SVR) is achievable in ⩾90% of hepatitis C-infected patients. SVR benefits are well-recognized with reductions in rates of liver complications, hepatocellular carcinoma and mortality. Additional benefits include reduced morbidity related to extrahepatic and systemic manifestations of hepatitis C such as renal, dermatologic, and metabolic complications. However, not all patients will derive all of these benefits and monitoring for progression is necessary, especially in those with more advanced fibrosis. To maximize the health benefits of SVR, counseling patients on best means to maintain good liver health and prevent reinfection are also important.

Hepatocellular carcinoma and lifestyles

The majority of hepatocellular carcinoma occurs over pre-existing chronic liver diseases that share cirrhosis as an endpoint. In the last decade, a strong association between lifestyle and hepatocellular carcinoma has become evident. Abundance of energy-rich food and sedentary lifestyles have caused metabolic conditions such as obesity and diabetes mellitus to become global epidemics. Obesity and diabetes mellitus are both tightly linked to non-alcoholic fatty liver disease and also increase hepatocellular carcinoma risk independent of cirrhosis. Emerging data suggest that physical activity not only counteracts obesity, diabetes mellitus and non-alcoholic fatty liver disease, but also reduces cancer risk. Physical activity exerts significant anticancer effects in the absence of metabolic disorders. Here, we present a systematic review on lifestyles and hepatocellular carcinoma.

Secondhand smoke induces hepatic apoptosis and fibrosis in hamster fetus

Secondhand smoke (SHS) is an important health issue worldwide. Inhaling SHS during pregnancy could cause abnormalities in the internal tissues of newborns, which may then impair fetal development and even cause severe intrauterine damage and perinatal death. However, the understanding of cytopathic mechanisms of SHS by maternal passive smoking on fetus liver during pregnancy is still limited. This study analyzed the effects of high-dose SHS (SHSH) on fetus liver using a maternal passive smoking animal model. Experiments showed that hepatic matrix metalloproteinase-9 activity and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling-positive cells were significantly increased in livers from fetuses of hamsters treated with SHSH. Similarly, expressions of both extrinsic and intrinsic apoptotic molecules were significantly higher in livers from fetuses of hamsters exposed to SHSH. Additionally, significantly increased inflammatory proteins, including transforming growth factor β, inducible nitric oxide synthase, and interleukin 1β, and fibrotic signaling molecules, including phosphorylated Smad2/3, SP1, and α-smooth muscle actin, were observed in the fetus livers from hamsters treated with SHSH. This study revealed that SHSH not only increased apoptosis through intrinsic and extrinsic pathways in the livers of fetuses from hamsters exposed to SHSH but also augmented hepatic fibrosis via Smad2/3 signaling.

Hepatocellular Carcinoma in Patients with a Sustained Response to Anti-Hepatitis C Therapy

Hepatocellular carcinoma (HCC) is a common, life-threatening complication of longstanding infection with the hepatitis C virus (HCV), likely a consequence of the direct oncogenic activity of the virus cooperating with liver cell inflammation in transforming the liver into a mitogenic and mutagenic environment. The achievement of a sustained virological response (SVR) to interferon-based therapies has been shown to benefit the course of hepatitis C in terms of reduced rates of liver-related complications and mortality from all causes. Interestingly, while achievement of an SVR is associated with a negligible risk of developing clinical decompensation over the years, the risk of HCC is not fully abrogated following HCV clearance, but it remains the dominant complication in all SVR populations. The factors accounting for such a residual risk of HCC in SVR patients are not fully understood, yet the persistence of the subverted architecture of the liver, diabetes and alcohol abuse are likely culprits. In the end, the risk of developing an HCC in SVR patients is attenuated by 75% compared to non-responders or untreated patients, whereas responders who develop an HCC may be stratified in different categories of HCC risk by a score based on the same demographic and liver disease-based variables, such as those that predict liver cancer in viremic patients. All in all, this prevents full understanding of those factors that drive HCC risk once HCV has been eradicated. Here, we critically review current understanding of HCC in SVR patients focusing on factors that predict residual risk of HCC among these patients and providing a glimpse of the expected benefits of new anti-HCV regimens based on direct antiviral agents.

Attributable causes of liver cancer mortality and incidence in china

OBJECTIVES

To estimate the proportion of liver cancer cases and deaths due to infection with hepatitis B virus (HBV), hepatitis C virus (HCV), aflatoxin exposure, alcohol drinking and smoking in China in 2005.

STUDY DESIGN

Systemic assessment of the burden of five modifiable risk factors on the occurrence of liver cancer in China using the population attributable fraction.

METHODS

We estimated the population attributable fraction of liver cancer caused by five modifiable risk factors using the prevalence data around 1990 and data on relative risks from meta-analyses, and large-scale observational studies. Liver cancer mortality data were from the 3rd National Death Causes Survey, and data on liver cancer incidence were estimated from the mortality data from cancer registries in China and a mortality/incidence ratio calculated.

RESULTS

We estimated that HBV infection was responsible for 65.9% of liver cancer deaths in men and 58.4% in women, while HCV was responsible for 27.3% and 28.6% respectively. The fraction of liver cancer deaths attributable to aflatoxin was estimated to be 25.0% for both men and women. Alcohol drinking was responsible for 23.4% of liver cancer deaths in men and 2.2% in women. Smoking was responsible for 18.7% and 1.0% . Overall, 86% of liver cancer mortality and incidence (88% in men and 78% in women) was attributable to these five modifiable risk factors.

CONCLUSIONS

HBV, HCV, aflatoxin, alcohol drinking and tobacco smoking were responsible for 86% of liver cancer mortality and incidence in China in 2005. Our findings provide useful data for developing guidelines for liver cancer prevention and control in China and other developing countries.

Ambovex(®) as a novel immunological modulator drug for the treatment of hepatocellular carcinoma (HCC) in the liver: a Phase II clinical trial

Hepatocellular carcinoma (HCC) is a global public health problem, based on it being the fifth most common cancer and third leading cause of cancer-related mortality worldwide. The approved conventional treatment methods for HCC have shown life-threatening side effects with limited or negligible success, especially in multifocal HCC. As a consequence, new therapeutic approaches are being explored, including immunoregulatory molecules that may have the potential to treat or delay the progression of HCC. A novel pharmaceutical botanical drug - Ambovex(®), an immune-modulator molecule - was tested to treat or delay the progress of HCC. We conducted a 6-month randomized clinical trial with an additional 3-month washing period (no treatment) to evaluate the safety and efficacy of low-dose Ambovex oral spray in treating patients with HCC. The clinical study involved a total of 40 patients, with 33 in the treatment group and seven in the control group. The α-fetoprotein (AFP) levels were measured every month and ultrasound scans were performed at time zero and every 2 months thereafter. Computed tomography (CT) scans were performed for patients in the treatment group. Ambovex proved to be safe, as there were no significant side effects although some patients found that the drug has unpleasant taste. AFP analysis showed a significant decrease in its level (α=0.05; 95% confidence interval) in the treatment group when compared to the control group at 3 months (P=0.0031) and at 6 months (P=0.007). The ultrasound results showed improvement in the treated group, as evidenced by a significant decrease in the lesion numbers and sizes. The lesions in 38% of treated patients decreased from multiple to single with major improvements; 35% of patients exhibited a decrease from multiple lesions to multiple lesions with minor improvements, whereas 27% had stabilized lesions. CT scans in the treated group showed significant improvement, as there was complete disappearance of the lesions after 6 months of treatment with Ambovex in two patients. This clinical study showed the effective and promising results of Ambovex as an immunological modulator in treating HCC. Further exploration of Ambovex is recommended.

ACG clinical guideline: the diagnosis and management of focal liver lesions

Focal liver lesions (FLL) have been a common reason for consultation faced by gastroenterologists and hepatologists. The increasing and widespread use of imaging studies has led to an increase in detection of incidental FLL. It is important to consider not only malignant liver lesions, but also benign solid and cystic liver lesions such as hemangioma, focal nodular hyperplasia, hepatocellular adenoma, and hepatic cysts, in the differential diagnosis. In this ACG practice guideline, the authors provide an evidence-based approach to the diagnosis and management of FLL.

Microfluidic immunoassay for rapid detection of cotinine in saliva

A microfluidic immunoassay is successfully developed for rapid analysis of cotinine saliva samples, which is a metabolite of nicotine and is widely used as a biomarker to evaluate the smoking status and exposure to tobacco smoke. The core microfluidic chip is fabricated by polydimethylsiloxane (PDMS) with standard soft lithography. Each chip is capable of eight parallel analyses of cotinine samples. The analyses can be completed within 40 min with 12 μl sample consumption. The linear detection range is 1 ~ 250 ng/ml and the minimum detectable concentration is 1 ng/ml respectively. The correlation coefficient of the calibration curve established from standard samples is 0.9989. The immunoassay was also validated by real saliva samples, and the results showed good reproducibility and accuracy. All the results were confirmed with traditional ELISA measurements. The result from microfluidic chip device and ELISA kits showed good correspondence, and the correlation coefficients are higher than 0.99. Compared with traditional technique, this microfluidic immunoassay is more economic, rapid, simple and sensitive, perfect for on-site cotinine measurements as well as for the evaluation of the exposure to tobacco smoking. Moreover, this immunoassay has potential to be applied in the analysis of other biomarkers in human saliva samples.

Impact of cigarette smoking on outcome of hepatocellular carcinoma after surgery in patients with hepatitis B

BACKGROUND AND OBJECTIVES

Cigarette smoking is a potential risk factor for hepatocellular carcinoma (HCC) initiation, partially through interaction with hepatitis B virus (HBV). We examined the hypothesis that cigarette smoking might be associated with HBV-related HCC recurrence and patient survival after curative surgery.

PATIENTS AND METHODS

Data of 302 patients with HBV infection who had undergone curative resection for HCC were prospectively collected from 2008 to 2011. Smoking status and smoking quantity (pack-years, PY) were asked at admission. Factors affecting recurrence-free survival (RFS) were examined. RFS and liver-specific mortality (LSM) stratified by risk factors were compared with log-rank test.

RESULTS

109 were current smokers. Current smokers were not different from non-smokers in tumor burden and surgical procedure. Univariate and multivariate analysis identified that heavy smoking (PY ≥ 20) was the most significant factor associated with HBV-related HCC recurrence after curative surgical resection (p = 0.001), followed by anti-HBV treatment (p<0.01), current smoking (p = 0.028), surgical margin <1 cm (p = 0.048) and blood transfusion >600 ml (p = 0.028). The median RFS in non-smokers, ex-smokers and current smokers was 34 months, 24 months and 26 months, respectively (p = 0.033). Current smokers had significantly worse RFS rate and increased 5-year cumulative LSM than non-smokers (p = 0.024, and p<0.001, respectively). Heavy smokers had significantly worse RFS than non- and light smokers (0

CONCLUSIONS

Smoking history and quantity appears to be risk factors for HBV-related HCC recurrence and LSM of patients after surgery. For smokers, continued smoking postoperatively might accelerate tumor recurrence and patient death. Therefore, smoking abstinence should be strongly recommended to patients pre- and postoperatively.

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Key Words Collapse

MESH Headings

• Carcinoma, Hepatocellular/complications
• Carcinoma, Hepatocellular/physiopathology
• Carcinoma, Hepatocellular/surgery
• Female
• Hepatitis B/complications
• Humans
• Liver Neoplasms/complications
• Liver Neoplasms/physiopathology
• Liver Neoplasms/surgery
• Male
• Middle Aged
• Prognosis
• Recurrence
• Smoking/physiopathology
• Nicotiana

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Affiliation(s)

Xu-Feng Zhang Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, China
Tao Wei Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, China
Xue-Min Liu Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, China
Chang Liu Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, China
Yi Lv Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, China

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Chinese herbal medicine-derived compounds for cancer therapy: a focus on hepatocellular carcinoma

ETHNOPHARMACOLOGICAL RELEVANCE

Hepatocellular carcinoma (HCC) as the major histological subtype of primary liver cancer remains one of the most common malignancies worldwide. Due to the complicated molecular pathogenesis of HCC, the option for effective systemic treatment is quite limited. There exists a critical need to explore and evaluate possible alternative strategies for effective control of HCC. With a long history of clinical use, Chinese herbal medicine (CHM) is emerging as a noticeable choice for its multi-level, multi-target and coordinated intervention effects against HCC. With the aids of phytochemistry and molecular biological approaches, in the past decades many CHM-derived compounds have been carefully studied through both preclinical and clinical researches and have shown great potential in novel anti-HCC natural product development. The present review aimed at providing the most recent developments on anti-HCC compounds derived from CHM, especially their underlying pharmacological mechanisms.

MATERIALS AND METHODS

A systematic search of anti-HCC compounds from CHM was carried out focusing on literatures published both in English (PubMed, Scopus, Web of Science and Medline) and in Chinese academic databases (Wanfang and CNKI database).

RESULTS

In this review, we tried to give a timely and comprehensive update about the anti-HCC effects and targets of several representative CHM-derived compounds, namely curcumin, resveratrol, silibinin, berberine, quercetin, tanshinone II-A and celastrol. Their mechanisms of anti-HCC behaviors, potential side effects or toxicity and future research directions were discussed.

CONCLUSION

Herbal compounds derived from CHM are of much significance in devising new drugs and providing unique ideas for the war against HCC. We propose that these breakthrough findings may have important implications for targeted-HCC therapy and modernization of CHM.

Is cancer risk still reduced if you give up smoking in later life?

SUMMARY This report summarizes the experimental and epidemiological evidence examining the ability of smoking cessation to influence cancer risk reduction in later life. Available evidence suggests that smoking cessation even in later years can significantly reduce mortality and yield risk reductions for many cancers including lung, oral, head and neck, and stomach cancer, among others. More research is necessary to accurately quantify the degree of cancer risk reduction for particular age groups and to calculate the minimum time of cessation necessary to produce a significant benefit for the patient. Smoking cessation is the only approach that has been shown to effectively reduce the risk of many cancers on a mass scale. Considering this, we recommend that healthcare providers communicate these benefits to patients at every opportunity and reinforce the notion that it is never too late to quit smoking.

A syndemic including cigarette smoking and sexual risk behaviors among a sample of MSM in Shanghai, China

OBJECTIVES

We explored possible correlates of cigarette smoking and their associations with levels of smoking among a sample of Chinese men who have sex with men (MSM). We also explored the syndemic associations of substance use and psychosocial problems on sexual risk behaviors.

METHODS

Cross-sectional data collection from 404 MSM in Shanghai, China.

RESULTS

MSM exhibit a high prevalence of smoking (66.3%). Both light and heavy smoking were associated with alcohol and drug use, depression, intimate partner violence, sexual attitudes, and gay identity (though the associations for light smokers were moderate compared to those for heavy smokers).

CONCLUSIONS

Our findings indicate the presence of a health syndemic among MSM, and suggest that smoking prevention and cessation and other substance abuse interventions should be integrated into efforts preventing sexual risk behaviors among MSM.

Causes of death in patients with hepatitis B: a natural history cohort study in the United States

The natural history of hepatitis B virus (HBV) infection in a U.S. population has not been well described. We identified the causes of death in 6,689 health plan members infected with HBV who were followed between March 1, 1996 and December 31, 2005. Causes of death were grouped into HBV-related (subdivided into decompensated cirrhosis [DCC] and hepatocellular carcinoma [HCC]), cancer, cardiovascular, and other/unknown. The study cohort included 3,244 females and 3,445 males; 68.3% were of Asian-Pacific Islander (API) descent, 11.8% were white (non-Hispanic), and 19.9% were of other or unknown race. Exposure to HBV antivirals and preexisting comorbidities were uncommon. Males had higher overall 10-year death rates than females, both for total deaths (8.9% versus 4.1%) and for HBV-related deaths (4.8% versus 1.2%). The death rate rose markedly with increasing age, and approximately 40% of all deaths in subjects over the age of 40 were HBV related. The death rate from HCC was twice that of DCC. HCC deaths represented 70% of cancer deaths in males and 37% in females. On multivariable analysis, when subjects with antecedent HCC and DCC were excluded, the only significant predictor of HBV mortality in both sexes was age.

CONCLUSION

HBV was the cause of death in over 40% of those who died during the study, and the mortality increased markedly with increasing age over 40 in males and over 50 in females. HBV-related mortality was four times more common in males than in females and was as common in non-Asians as in those of API origin. HBV-related deaths were twice as common from HCC as from DCC.

A novel perspective and approach to intestinal octreotide absorption: sinomenine-mediated reversible tight junction opening and its molecular mechanism

In this work, we assessed the effects of sinomenine (SN) on intestinal octreotide (OCT) absorption both in Caco-2 cell monolayers and in rats. We also investigated the molecular mechanisms of tight junction (TJ) disruption and recovery by SN-mediated changes in the claudin-1 and protein kinase C (PKC) signaling pathway. The data showed that exposure to SN resulted in a significant decrease in the expression of claudin-1, which represented TJ weakening and paracellular permeability enhancement. Then, the recovery of TJ after SN removal required an increase in claudin-1, which demonstrated the transient and reversible opening for TJ. Meanwhile, the SN-mediated translocation of PKC-α from the cytosol to the membrane was found to prove PKC activation. Finally, SN significantly improved the absolute OCT bioavailability in rats and the transport rate in Caco-2 cell monolayers. We conclude that SN has the ability to enhance intestinal OCT absorption and that these mechanisms are related at least in part to the important role of claudin-1 in SN-mediated, reversible TJ opening via PKC activation.

Etiological and molecular profile of hepatocellular cancer from India

Hepatocellular carcinoma (HCC) cases are underreported in India. Our study was designed to investigate the etiological profile of HCC cases in India and compare with global incidence. The study included 348 HCC and 375 chronic liver disease cases without HCC as controls. Samples were screened for hepatitis B virus (HBV)/hepatitis C virus (HCV) infections using enzyme-linked immunosorbent assay and polymerase chain reaction (PCR). HBV-DNA and HCV-RNA genotyping was performed by PCR-restriction fragment length polymorphism. All cases were also assessed for other possible risk factors of HCC. Among HCC cases, 62.6% were positive for HBV, 26.7% for HCV and 3.2% had coinfection. Around 17% of HCC cases had aflatoxin-B1 exposure. HBV genotype D (odds ratio, OR = 1.76) and mixed genotypes (OR = 6.86) had higher risk of HCC development. The risk of HCC was twofold (OR = 2.26) in patients with high HBV-DNA levels. Moreover, our findings were unable to establish a clear differential effect of HCV genotype (OR = 1.48) and high viral load (OR = 1.21) on HCC development. In India, HBV is the major risk factors, whereas alcohol, smoking and diabetes are nonsignificantly associated. Asian countries such as Hong Kong and Taiwan also had high incidence of HBV-related HCC. Contrarily, countries from Europe and USA reported HCV as predominant cause of HCC. Further, aflatoxin could be a possible risk of HCC in the population. However, in comparison to the countries such as China and Taiwan (high Aflatoxin exposure), the aflatoxin level is relatively low in our patients. High HBV-DNA levels and HBV/D increased the risk of HCC. However, neither genotype nor virus loads of HCV affected prognosis of HCC patients in our study.

New therapeutic paradigm for patients with cirrhosis

Cirrhosis is a major health problem, being the 5th cause of death in the U.K. and 12th in the U.S., but 4th in the 45 to 54 age group. Until recently cirrhosis was considered a single and terminal disease stage, with an inevitably poor prognosis. However, it is now clear that 1-year mortality can range from 1% in early cirrhosis to 57% in decompensated disease. As the only treatment for advanced cirrhosis is liver transplantation, what is urgently needed is strategies to prevent transition to decompensated stages. The evidence we present in this review clearly demonstrates that management of patients with cirrhosis should change from an expectant algorithm that treats complications as they occur, to preventing the advent of all complications while in the compensated phase. This requires maintaining patients in an asymptomatic phase and not significantly affecting their quality of life with minimal impairment due to the therapies themselves. This could be achieved with lifestyle changes and combinations of already licensed and low-cost drugs, similar to the paradigm of treating risk factors for cardiovascular disease. The drugs are propranolol, simvastatin, norfloxacin, and warfarin, which in combination would cost £128/patient annually-equivalent to U.S. $196/year. This treatment strategy requires randomized controlled trials to establish improvements in outcomes. In the 21st century, cirrhosis should be regarded as a potentially treatable disease with currently available and inexpensive therapies.

KASL Clinical Practice Guidelines: Management of chronic hepatitis B

The guideline on the management of chronic hepatitis B (CHB) was first developed in 2004 and revised in 2007 by the Korean Association for the Study of the Liver (KASL). Since then there have been many developments, including the introduction of new antiviral agents and the publications of many novel research results from both Korea and other countries. In particular, a large amount of knowledge on antiviral resistance--which is a serious issue in Korea--has accumulated, which has led to new strategies being suggested. This prompted the new guideline discussed herein to be developed based on recent evidence and expert opinion.

TARGET POPULATION

The main targets of this guideline comprise patients who are newly diagnosed with CHB and those who are followed or treated for known CHB. This guideline is also intended to provide guidance for the management of patients under the following special circumstances: malignancy, transplantation, dialysis, coinfection with other viruses, pregnancy, and children.

Hepatitis B and C virus infection and hepatocellular carcinoma in China: a review of epidemiology and control measures

China has one of the highest carrier prevalences of hepatitis B virus (HBV) in the world: nearly 10% of the general population. The disease burden of HBV infection and hepatocellular carcinoma (HCC) is also believed to be among the world's largest, and that of hepatitis C virus (HCV) infection is likely to be substantial as well. However, the epidemiology and measures to control HBV and HCV infection in China remain relatively unknown outside the country. We review the epidemiology of HBV and HCV infection, the disease burden of and risk factors for HCC, and current control measures against HBV and HCV infection in China. We also discuss the relevant literature and implications for future studies of hepatitis and HCC in China.

Hepatitis B and C virus infection and hepatocellular carcinoma in China: a review of epidemiology and control measures

China has one of the highest carrier prevalences of hepatitis B virus (HBV) in the world: nearly 10% of the general population. The disease burden of HBV infection and hepatocellular carcinoma (HCC) is also believed to be among the world’s largest, and that of hepatitis C virus (HCV) infection is likely to be substantial as well. However, the epidemiology and measures to control HBV and HCV infection in China remain relatively unknown outside the country. We review the epidemiology of HBV and HCV infection, the disease burden of and risk factors for HCC, and current control measures against HBV and HCV infection in China. We also discuss the relevant literature and implications for future studies of hepatitis and HCC in China.

Role of aflatoxin B1 as a risk for primary liver cancer in north Indian population

OBJECTIVES

The present study was designed to determine whether aflatoxin B1 (AFB1) exposure has any role to play in hepatocellular carcinoma (HCC) patients from northern India.

DESIGN AND METHODS

A total of 266 HCC patients and 251 patients of chronic liver disease without-HCC were enrolled into the study. All samples were screened for serological markers for hepatitis B and C infections and levels of AFB1 in food and urine samples.

RESULTS

A threefold (OR=3.43) and five-fold (OR=5.47) increased risk of HCC was observed amongst HBV infection and AFB1-levels in food and urine samples, respectively. However, a non-significant risk was observed with respect to HCV infection (OR=1.27) and alcohol consumption (OR=1.18). A threefold (OR=3.15) increased risk of HCC was observed amongst cases of non-viral etiology with respect to urinary AFB1.

CONCLUSION

The data provides an exposure and disease risk information for establishing intervention studies to diminish the impact of aflatoxin exposure in Indian population.

Interaction between cigarette smoking and hepatitis B and C virus infection on the risk of liver cancer: a meta-analysis

INTRODUCTION

Chronic infection with hepatitis B (HBV) and C viruses (HCV) as well as cigarette smoking are established risk factors of hepatocellular carcinoma (HCC), but it is unclear whether an interaction exists between these factors in causing hepatocellular carcinogenesis. We conducted a meta-analysis to evaluate the interaction of HBV and HCV infection and cigarette smoking on the risk of HCC.

METHODS

We systematically searched the PUBMED and the China National Knowledge Infrastructure databases. A total of 16 eligible publications were identified. Cigarette smoking and chronic HBV and HCV infections were dichotomized into present or absent. Additive (S) and multiplicative interaction indexes (V) between smoking and each of the two infections and their 95% confidence intervals (95% CI) were calculated for each study and then combined in a meta-analysis.

RESULTS

We found a more than additive interaction between HBV infection and cigarette smoking (S=1.44; 95% CI, 1.00-2.06; nine studies) and a more than multiplicative interaction (V=1.60; 95% CI, 1.16-2.20; six studies) between HCV infection and cigarette smoking. No publication bias was detected.

CONCLUSION

Smoking seems to interact with both HBV and HCV in determining HCC risk. A pooled analysis of individual subject data, with appropriate adjustment with other risk factors, is warranted to confirm these results.

IMPACT

The results of this study imply the evidence of a synergistic effect between smoking and HBV or HCV infection on the risk of HCC. Thus, chronic carriers of HBV or HCV are recommended to avoid smoking.

Case-spouse control design in practice: an experience in estimating smoking and chronic obstructive pulmonary disease deaths in Chinese adults

BACKGROUND/PURPOSE

We assessed the effect of smoking on death from chronic obstructive pulmonary disease (COPD) in China by employing a large population-based, case-spouse control study design using data from a nationwide survey of mortality.

METHODS

During 1989-1991, a nationwide retrospective survey of mortality was conducted in China. For approximately 1,000,000 adults dying from all causes during 1986-1988, their surviving spouses or other informants provided detailed information about their own as well as the deceased person's smoking history. For this study, 183,393 individuals who died of COPD at age > or = 40 years were taken as cases, while 272,984 sex-matched surviving spouses of subjects who died from any cause were taken as controls.

RESULTS

COPD death rates for smokers were more than twice as high as those of non-smokers, with a dose-response risk pattern, despite the fact that COPD death rates varied widely by region and age. Tobacco accounted for 41.4% of COPD deaths in men, but only 13.5% of those in women, who had a lower rate of smoking.

CONCLUSION

A case-spouse control study, as an alternative design, is valid and feasible in utilizing information from population-based, retrospective mortality survey data for an analytical epidemiological study of disease etiology.

Using a population-based approach to prevent hepatocellular cancer in New South Wales, Australia: effects on health services utilisation

BACKGROUND

Australians born in countries where hepatitis B infection is endemic are 6-12 times more likely to develop hepatocellular cancer (HCC) than Australian-born individuals. However, a program of screening, surveillance and treatment of chronic hepatitis B (CHB) in high risk populations could significantly reduce disease progression and death related to end-stage liver disease and HCC. Consequently we are implementing the B Positive pilot project, aiming to optimise the management of CHB in at-risk populations in south-west Sydney. Program participants receive routine care, enhanced disease surveillance or specialist referral, according to their stage of CHB infection, level of viral load and extent of liver injury. In this paper we examine the program's potential impact on health services utilisation in the study area.

METHODS

Estimated numbers of CHB infections were derived from Australian Bureau of Statistics data and applying estimates of HBV prevalence rates from migrants' countries of birth. These figures were entered into a Markov model of disease progression, constructing a hypothetical cohort of Asian-born adults with CHB infection. We calculated the number of participants in different CHB disease states and estimated the numbers of GP and specialist consultations and liver ultrasound examinations the cohort would require annually over the life of the program.

RESULTS

Assuming a 25% participation rate among the 5,800 local residents estimated to have chronic hepatitis B infection, approximately 750 people would require routine follow up, 260 enhanced disease surveillance and 210 specialist care during the first year after recruitment is completed. This translates into 5 additional appointments per year for each local GP, 25 for each specialist and 420 additional liver ultrasound examinations.

CONCLUSIONS

While the program will not greatly affect the volume of local GP consultations, it will lead to a significant increase in demand for specialist services. New models of CHB care may be required to aid program implementation and up scaling the program will need to factor in additional demands on health care utilisation in areas of high hepatitis B sero-prevalence.

Behaviour does not fully explain the high risk of chronic liver disease in less educated men in Hungary

BACKGROUND

Hungary has among the highest mortality rates from chronic liver disease (CLD) and cirrhosis in Europe. Usually, conventional behavioural factors are hypothesized as the cause of the high risk of CLD.

METHODS

A case-control study was performed with 287 cases and 892 controls to study the relationship between socio-economic and behavioural factors and the risk of CLD. Liver disease was verified by physical examination and blood tests. Blood samples were collected for detecting hepatitis B, C and E virus infection. Information on exposure factors was recorded by the participating physicians and by self-administered questionnaire. Simple regression analysis was used to study the relationship between CLD/cirrhosis and potential risk factors as alcohol intake (amount and source), problem drinking, cigarette smoking, physical activity, viral hepatitis infections, socio-economic factors (education, financial and marital status). Multiple regression analysis was used to identify whether the effect of socio-economic factors is fully mediated by health behaviour (smoking, alcohol consumption, physical activity).

RESULTS

The univariate analysis showed that heavy alcohol consumption, problem drinking, former and heavy cigarette smoking, single, separated or divorced marital status, bad or very bad perceived financial status and lower education significantly increased the risk of CLD/cirrhosis. The effect of marital status and of education did not change after adjustment for behavioural factors, but the effect of perceived financial status disappeared.

CONCLUSIONS

The effect of low socio-economic status on the risk of CLD/cirrhosis is only partially explained by conventional behavioural risk factors in Hungary.

Estimation of cancer incidence and mortality attributable to smoking in China

BACKGROUND

Tobacco smoking, as a cause of cancer, is common in China. Few studies have been conducted to assess the burden of tobacco-related cancer in the Chinese population.

METHODS

We calculated the proportion of cancers attributable to tobacco smoking to estimate the burden of tobacco-related cancer. Population attributable fraction was calculated based on the assumption of total avoidance of smoking. Data on smoking prevalence were from two large-scale national surveys of representative samples of the Chinese population. Data on relative risk were derived from the meta-analyses and large-scale studies. Cancer mortality and incidence were originated from the third national death cause survey and cancer registries in China.

RESULTS

We estimated that a total of 405,112 deaths of cancer were attributable to smoking in China in 2005, including 372,264 among men (32.7% of all cancer deaths) and 32,848 among women (5.0%). A total of 495,221 cancer cases were attributable to smoking, including 454,785 among men (30.0% of all cancer cases) and 40,436 among women (3.9%). Involuntary smoking was responsible for 11,507 lung cancer deaths (11.1%) among non-smoking women.

CONCLUSION

Tobacco smoking is responsible for one-third of the total cancer deaths among men. Involuntary smoking is an important individual risk factor for lung cancer among non-smoking women. There is a need to continue and strengthen tobacco-control programs and initiatives to reduce smoking-related cancer burden in China.

Cigarette smoking and serum liver enzymes: the role of alcohol and inflammation

BACKGROUND AND AIMS

Smoking may affect the liver through inflammatory pathways and may aggravate the pathogenic effects of alcohol on the liver. We have examined the relationship between cigarette smoking and liver enzymes and the role of alcohol and C-reactive protein (CRP), a marker of inflammation.

METHODS

The subjects consisted of 4595 men aged 40-59 y with no history of coronary heart disease drawn from general practices in 24 British towns.

RESULTS

Cigarette smoking was significantly associated with increased levels of gamma-glutamyl transferase (GGT) and alkaline phosphatase (ALP) (P < 0.0001) and was inversely associated with increased aspartate aminotransferase (AST) after adjustment for alcohol intake, body mass index and physical activity. Compared with never smokers, heavy cigarette smokers (> or =40/day) were associated with increased odds of elevated GGT (> or =23 IU/L) (adjusted odds ratio [OR] 1.56 [1.08, 2.27]), which was abolished after adjustment for CRP (adjusted OR 1.27 [0.87, 1.86]). There was a significant interaction between smoking and alcohol on GGT. In the absence of heavy drinking, there was no association between smoking and GGT after adjustment for CRP. Among heavy drinkers, smoking was associated with increased levels of GGT independent of CRP. Smoking was associated with increased odds of elevated ALP (> or =11 IU/L) (adjusted OR 3.95 [2.77, 5.62]), which persisted after adjustment for CRP and white cell count (adjusted OR 2.90 [1.99-4.23]), possibly reflecting increased bone cell activity.

CONCLUSION

The findings suggest that cigarette smoking does not cause liver injury, but may enhance the effects of alcohol on liver cell injury in heavy drinkers.

Sulfur dioxide and benzo(a)pyrene modulates CYP1A and tumor-related gene expression in rat liver

Sulfur dioxide (SO(2)) and benzo(a)pyrene (B(a)P) are common industrial and environmental contaminants. However, few data are available on the effects of SO(2) on proto-oncogenes and tumor suppressor genes, as well as the interactions between SO(2) and other xenobiotics regulating proto-oncogenes or tumor suppressor genes expression. To investigate the interactions between SO(2) and B(a)P, male Wistar rats were exposed to intratracheally instilled with B(a)P or SO(2) inhalation alone or together. We detected mRNA expression of CYP1A1 and 1A2, 7-ethoxyresorufin O-deethylase (EROD), and methoxyresorufin O-demethylase (MROD) activities in livers. The mRNA and protein levels of several cancer-related genes were analyzed in livers by real-time RT-PCR and Western blot, respectively. The EROD/MROD activities and CYP1A1/2 expression were down-regulated by SO(2) but up-regulated by B(a)P alone. Exposure of SO(2) alone induced c-fos, c-jun, c-myc, H-ras, and p53 expression, and depressed p16 and Rb expression in livers. The effects of B(a)P on the above gene were similar to SO(2) except c-fos expression. Furthermore, SO(2) + B(a)P exposure increased the expression of c-fos, c-jun, c-myc, and p53, and decreased p16 and Rb expression in livers compared with exposed to SO(2) or B(a)P alone. However, no synergistic effects were observed on H-ras and CYP1A1/2 after SO(2) + B(a)P exposure. Our findings indicate that multiple cell cycle regulatory proteins play key roles in the toxicity of SO(2) and B(a)P in livers. It might involve the activation of c-fos, c-jun, c-myc, and p53. And p16-Rb pathway might also participate in the progress. Although the gene products we studied are classed as oncogenes and tumor suppressor genes, their functions actually relate to more general processes of control of cell proliferation, survival, and/or apoptosis.

Smoking is associated with steatosis and severe fibrosis in chronic hepatitis C but not B

OBJECTIVE

The results of retrospective studies suggest an association between smoking, insulin resistance, steatosis and fibrosis in patients with chronic hepatitis C (CHC); no data are available for chronic hepatitis B (CHB). The purpose of this study was to evaluate the relationship, if any, of such factors on liver fibrosis in a cohort of patients with CHB and CHC.

MATERIAL AND METHODS

The study prospectively included 271 consecutive patients with CHB (n=95) or CHC (n=176) who had undergone liver biopsies. Each patient completed a questionnaire on smoking habits; anthropometric measurements and laboratory examinations were carried out and histological lesions were recorded.

RESULTS

In CHC patients, severe fibrosis was independently associated with a higher body mass index (BMI) (OR: 1.180, 95% CI: 1.028-1.354; p=0.019), heavy smoking (OR: 3.923, 95% CI: 1.356-11.348; p=0.012), higher alanine aminotransferase (ALAT) levels (OR: 1.010, 95% CI: 1.003-1.017; p=0.005) and alkaline phosphatase (ALP) levels (OR: 1.016, 95% CI: 1.001-1.030; p=0.03) and presence of necroinflammation (OR: 11.165, 95% CI: 1.286-96.970; p=0.029). Moreover, steatosis was independently associated with high gamma-glutamyl transpeptidase (GGT) values, heavy smoking and presence of necroinflammation. In CHB patients, no association between smoking habits and fibrosis or steatosis was noted.

CONCLUSIONS

Heavy smoking is associated with severe fibrosis in CHC but not CHB. Heavy smoking is also significantly associated with steatosis in CHC and this could be the link between smoking and fibrosis progression.