Reduced coffee consumption among individuals with primary sclerosing cholangitis but not primary biliary cirrhosis

Prevalence and clinical profiles of primary sclerosing cholangitis in China: Data from electronic medical records and systematic literature retrieval

BACKGROUND & AIMS

Epidemiology of primary sclerosing cholangitis (PSC) is lacking in China. We aimed to estimate the period prevalence and depict the clinical features of PSC in China.

METHODS

We identified and included PSC cases between 2000 and 2023 from two sources: electronic medical records (EMR) and systematical literature retrieval (SLR). The period prevalence of PSC was estimated by the multiplier method. Rate ratios (RRs) for PSC prevalence in relation to macroeconomic indicators were calculated by the negative binomial regression model.

RESULTS

A total of 1358 PSC cases were retrieved from 299 hospitals (162 from EMR and 1196 from SLR). Males accounted for 55.7 % of the PSC cases and 25.7 % had concomitant inflammatory bowel disease (IBD). The estimated period prevalence of PSC from 2000 to 2023 was 2.36 (95 % CI: 1.82, 3.34) per 100,000. Males had a numerically higher PSC prevalence than females (2.56, 95 % CI: 1.97, 3.63 vs. 2.14, 95 % CI: 1.65, 3.04 per 100,000). The highest prevalence of PSC was in East China at 4.87 (95 % CI: 3.44, 7.18) per 100,000, followed by North China at 2.94 (95 % CI: 2.33, 3.74) per 100,000, and the lowest in South China at 0.92 (95 % CI: 0.66, 1.30) per 100,000. Regional per capita GDP (RR 1.65, 95 % CI: 1.03, 2.65) and healthcare expenditure (RR 1.94, 95 % CI: 1.13, 3.38) were identified to be associated with PSC prevalence.

CONCLUSION

Our study showed the estimated PSC prevalence varied within China, but was generally lower than that in Western countries.

Coffee, adenosine, and the liver

A variety of observational studies have demonstrated that coffee, likely acting through caffeine, improves health outcomes in patients with chronic liver disease. The primary pharmacologic role of caffeine is to act as an inhibitor of adenosine receptors. Because key liver cells express adenosine receptors linked to liver injury, regeneration, and fibrosis, it is plausible that the biological effects of coffee are explained by effects of caffeine on adenosinergic signaling in the liver. This review is designed to help the reader make sense of that hypothesis, highlighting key observations in the literature that support or dispute it.

The microbiota and the gut-liver axis in primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) offers unique opportunities to explore the gut-liver axis owing to the close association between liver disease and colonic inflammation. It is well established that the gut microbiota in people with PSC differs from that of healthy individuals, but details of the microbial factors that demarcate PSC from inflammatory bowel disease (IBD) without PSC are poorly understood. In this Review, we aim to provide an overview of the latest literature on the gut microbiome in PSC and PSC with IBD, critically examining hypotheses on how microorganisms could contribute to the pathogenesis of PSC. A particular emphasis will be put on pathogenic features of the gut microbiota that might explain the occurrence of bile duct inflammation and liver disease in the context of IBD, and we postulate the potential existence of a specific yet unknown factor related to the gut-liver axis as causative in PSC. Available data are scrutinized in the perspective of therapeutic approaches related to the gut-liver axis.

Missing Causality and Heritability of Autoimmune Hepatitis

BACKGROUND

Autoimmune hepatitis has an unknown cause and genetic associations that are not disease-specific or always present. Clarification of its missing causality and heritability could improve prevention and management strategies.

AIMS

Describe the key epigenetic and genetic mechanisms that could account for missing causality and heritability in autoimmune hepatitis; indicate the prospects of these mechanisms as pivotal factors; and encourage investigations of their pathogenic role and therapeutic potential.

METHODS

English abstracts were identified in PubMed using multiple key search phases. Several hundred abstracts and 210 full-length articles were reviewed.

RESULTS

Environmental induction of epigenetic changes is the prime candidate for explaining the missing causality of autoimmune hepatitis. Environmental factors (diet, toxic exposures) can alter chromatin structure and the production of micro-ribonucleic acids that affect gene expression. Epistatic interaction between unsuspected genes is the prime candidate for explaining the missing heritability. The non-additive, interactive effects of multiple genes could enhance their impact on the propensity and phenotype of autoimmune hepatitis. Transgenerational inheritance of acquired epigenetic marks constitutes another mechanism of transmitting parental adaptations that could affect susceptibility. Management strategies could range from lifestyle adjustments and nutritional supplements to precision editing of the epigenetic landscape.

CONCLUSIONS

Autoimmune hepatitis has a missing causality that might be explained by epigenetic changes induced by environmental factors and a missing heritability that might reflect epistatic gene interactions or transgenerational transmission of acquired epigenetic marks. These unassessed or under-evaluated areas warrant investigation.

Caffeine and rheumatoid arthritis: A complicated relationship

The current ideal goal of rheumatoid arthritis (RA) management is to resolve joint and systemic inflammation by using pharmacological interventions, assuming this will correspondingly lead to overall well-being. Nonetheless, it has emerged that a substantial number of RA patients do not reach optimal disease control. Thus suggesting the holistic management of subjective symptoms might be overlooked. This poses significant medical challenges; hence the proposal of incorporating lifestyle interventions as part of a multidimensional approach. Among these aspects, both patients and physicians perceive the important role of nutrition. This review shall examine how caffeine, one of the most studied bioactive components of the most widely consumed beverages, may potentially interfere with RA management. In particular, the mechanism by which caffeine affects RA pathogenesis, as a trigger for RA onset or flare, including its influence on rheumatic drug metabolism and the most common RA comorbidities and constitutional symptoms are outlined, highlighting important knowledge gaps and unmet research needs.

High-Resolution Exposomics and Metabolomics Reveals Specific Associations in Cholestatic Liver Diseases

Progress in development of prognostic and therapeutic options for the rare cholestatic liver diseases, primary sclerosing cholangitis (PSC) and primary biliary cholangitis (PBC), is hampered by limited knowledge of their pathogeneses. In particular, the potential role of hepatotoxic and/or metabolism-altering environmental chemicals in the pathogenesis of these diseases remains relatively unstudied. Moreover, the extent to which metabolic pathways are altered due to ongoing cholestasis and subsequent liver damage or possibly influenced by hepatotoxic chemicals is poorly understood. In this study, we applied a comprehensive exposomics-metabolomics approach to uncover potential pathogenic contributors to PSC and PBC. We used untargeted high-resolution mass spectrometry to characterize a wide range of exogenous chemicals and endogenous metabolites in plasma and tested them for association with disease. Exposome-wide association studies (EWAS) identified environmental chemicals, including pesticides, additives and persistent pollutants, that were associated with PSC and/or PBC, suggesting potential roles for these compounds in disease pathogenesis. Metabolome-wide association studies (MWAS) found disease-associated alterations to amino acid, eicosanoid, lipid, co-factor, nucleotide, mitochondrial and microbial metabolic pathways, many of which were shared between PSC and PBC. Notably, this analysis implicates a potential role of the 5-lipoxygenase pathway in the pathogenesis of these diseases. Finally, EWAS × MWAS network analysis uncovered linkages between environmental agents and disrupted metabolic pathways that provide insight into potential mechanisms for PSC and PBC. Conclusion: This study establishes combined exposomics-metabolomics as a generalizable approach to identify potentially pathogenic environmental agents and enumerate metabolic alterations that may impact PSC and PBC, providing a foundation for diagnostic and therapeutic strategies.

Patients with Autoimmune Hepatitis Report Lower Lifetime Coffee Consumption

BACKGROUND

Coffee drinking has been associated with decreased risk of some autoimmune diseases as well liver disease and outcomes. Environmental factors, such as coffee consumption, are yet to be assessed among patients with autoimmune hepatitis (AIH).

AIM

We sought to investigate the relationship between coffee consumption and risk of AIH utilizing the Genetic Repository of Autoimmune Liver Disease and Contributing Exposures (GRACE) database.

METHODS

Lifetime coffee drinking was collected from 358 AIH patients (cases) and 564 volunteers (controls) from primary care visits. Groups were compared utilizing the Wilcoxon rank sum test for continuous variables and the Chi-square test for discrete variables. Logistic regression was used to analyze the effects of different coffee parameters (time, frequency, and cups) after adjusting for age, sex, education, smoking status, BMI, and daily activity.

RESULTS

24.6% of AIH patients never drank coffee compared to 15.7% of controls (p < 0.001), and only 65.6% were current drinkers compared with 77% of controls (p < 0.001). Among "ever" coffee drinkers, AIH patients consumed fewer lifetime cups of coffee per month (45 vs. 47 for controls, p < 0.001) and spent less percentage of life drinking coffee (62.5% vs. 69.1% for controls, p < 0.001). Concurrent inflammatory bowel disease was higher among AIH patients than controls (5.7% vs. 1.2%, p < 0.001), yet did not significantly contribute to "never" coffee drinking status. The relationship between lower coffee consumption and AIH persisted even after controlling for covariates.

CONCLUSIONS

Coffee consumption is lower among patients with AIH compared to controls.

We Are Not Immune: Racial and Ethnic Disparities in Autoimmune Liver Diseases

Autoimmune liver diseases are attributed to a complex interplay of biologic, acquired, and environmental factors. Increased prevalence, later stage at presentation, worse response to standard therapy, and transplant-related disparities have all been reported in racial and ethnic minorities such as Black and Latinx patients with autoimmune liver diseases. While biology and inherited genetic predispositions may partly explain these disparities, definitive and universal genetic variations underlying these differences in outcomes have not been defined. Nonetheless, socioeconomic status, access to health care, environmental and societal factors, and implicit provider bias can all contribute to poor patient outcomes. There remains an unmet need to understand and mitigate the factors contributing to health inequity in autoimmune liver diseases. In this review, we summarize the data on racial and ethnic disparities in presentation, treatment response, and outcomes pertaining to autoimmune liver diseases in minority populations, on the premise that understanding disparities is the first step toward reaching health equity.

Environmental risk factors are associated with autoimmune hepatitis

BACKGROUND

Failure of immunologic homeostasis and resultant hepatocyte destruction in autoimmune hepatitis (AIH) is likely the result of environmental triggers within a permissive genetic architecture.

AIMS

We aimed to identify risk factors associated with AIH in a well-phenotyped AIH cohort.

METHODS

We prospectively collected environmental questionnaires from 358 AIH cases and 563 healthy controls. Response frequencies were compared using logistic regression, adjusting for age at recruitment, sex and education.

RESULTS

AIH cases were more likely to ever have a urinary tract infection (UTI) (53.6% vs 33.9%, P < .001) and recurrent UTI (more than 1 per year) (23.5% vs 15.9%, P = .002) compared to controls. Female cases more frequently had ever used oral contraceptives (83.0% vs 73.7%, P = .006), fewer pregnancies (median = 1 vs 3, P < .001) and less often used hormone replacement therapy compared to controls (28.5% vs 60.1%, P < .001). Current smoking was more prevalent in cases (18.9% vs 7.4%, P = .022), yet no difference according to historical smoking behaviours was observed. Finally, cases were less likely to have history of mumps (32.4% vs 53.1%, P = .011) and rheumatic fever (1.1% vs 4.4%, P = .028), but reported higher vaccination frequency to chicken pox (38% vs 28.1%), measles (66.5% vs 39.3%), mumps (58.7% vs 34.6%), rubella (55.3% vs 32.7%), pertussis (59.8% vs 40.1%) and pneumococcus (47.2% VS 39.4%) (P < .002).

CONCLUSIONS

Environmental factors are important in AIH pathogenesis. Replication of these findings and prospective examination may provide new insight into AIH onset and outcomes.

[Novel Insights of Primary Sclerosing Cholangitis and Primary Biliary Cholangitis]

Primary sclerosing cholangitis (PSC) and primary biliary cholangitis (PBC) are immune-mediated chronic liver diseases. PSC is a rare disorder characterized by multi-focal bile duct strictures and progressive liver diseases that ultimately results in the need for liver transplantation in most patients. Imaging studies, such as MRCP, have an essential role in the diagnosis of most cases of PSC. PSC is usually accompanied by inflammatory bowel disease, and there is a high risk of cholangiocarcinoma and colorectal cancer in PSC. No medical therapies have been proven to delay the progression of PSC. Endoscopic intervention for tissue diagnosis or biliary drainage is frequently required in cases of PSC with a dominant stricture, acute cholangitis, or clinically suspected cholangiocarcinoma. PBC is a chronic inflammatory autoimmune cholestatic liver disease, which, when untreated, will culminate in end-stage biliary cirrhosis requiring liver transplantation. A diagnosis is usually based on the presence of serum liver tests indicative of cholestatic hepatitis in association with circulating antimitochondrial antibodies. Patient presentation and course can be diverse in PBC, and risk stratification is important for ensuring that all patients receive a personalized approach to their care. Medical therapy using ursodeoxycholic acid or obeticholic acid has an important role in reducing the progression to end-stage liver disease in PBC.

Primary sclerosing cholangitis and the risk of cancer, cardiovascular disease, and all-cause mortality: a systematic review and meta-analysis of cohort studies

A diagnosis of primary sclerosing cholangitis (PSC) has been associated with increased risk of hepatobiliary cancers, colorectal cancer and all-cause mortality in several studies, while associations with cardiovascular disease have been inconsistent. We conducted a systematic review and meta-analysis of published cohort studies on the topic to summarize these associations. PubMed and Embase databases were searched up to January 13th, 2020. Cohort studies on PSC and risk of cancer, cardiovascular disease, or mortality were included. Summary relative risks (RRs) and 95% confidence intervals (95% CIs) were estimated using random effects models. The summary RR (95% CI) comparing persons with PSC to persons without PSC was 584.37 (269.42-1267.51, I² = 89%, n = 4) for cholangiocarcinoma (CCA), 155.54 (125.34-193.02, I² = 0%, n = 3) for hepatobiliary cancer, 30.22 (11.99-76.17, I² = 0%, n = 2) for liver cancer, 16.92 (8.73-32.78, I² = 88%, n = 4) for gastrointestinal cancer, 7.56 (2.42-23.62, I² = 0%, n = 3) for pancreatic cancer, 6.10 (4.19-8.87, I² = 14%, n = 7) for colorectal cancer (CRC), 4.13 (2.99-5.71, I² = 80%, n = 5) for total cancer, 3.55 (2.94-4.28, I² = 46%, n = 5) for all-cause mortality, and 1.57 (0.25-9.69, I² = 79%, n = 2) for cardiovascular disease. Strong positive associations were observed between PSC and risk of CCA, hepatobiliary cancer, liver cancer, gastrointestinal cancer, pancreatic cancer, CRC, total cancer, and all-cause mortality, but not for cardiovascular disease.

Preventative care in cholestatic liver disease: Pearls for the specialist and subspecialist

Cholestatic liver diseases (CLDs) encompass a variety of disorders of abnormal bile formation and/or flow. CLDs often lead to progressive hepatic insult and injury and following the development of cirrhosis and associated complications. Many such complications are clinically silent until they manifest with severe sequelae, including but not limited to life-altering symptoms, metabolic disturbances, cirrhosis, and hepatobiliary diseases as well as other malignancies. Primary sclerosing cholangitis (PSC) and primary biliary cholangitis (PBC) are the most common CLDs, and both relate to mutual as well as unique complications. This review provides an overview of PSC and PBC, with a focus on preventive measures aimed to reduce the incidence and severity of disease-related complications.

Effects of Caffeine Treatment on Hepatopulmonary Syndrome in Biliary Cirrhotic Rats

Hepatopulmonary syndrome (HPS) is a lethal complication of cirrhosis characterized by hypoxia and overt intrapulmonary shunting. In this study, we investigated the effect of caffeine in rats with common bile duct ligation (CBDL)-induced liver cirrhosis and HPS. CBDL rats were randomly allocated to receive caffeine or vehicle for 14 days. On the 28th day after CBDL, mortality rate, hemodynamics, liver, and renal biochemistry parameters and arterial blood gas analysis were evaluated. Lung and liver were dissected for the evaluation of inflammation, angiogenesis and protein expressions. In another series with parallel groups, the intrapulmonary shunting was determined. Caffeine significantly reduced portal pressure (caffeine vs. control: 10.0 ± 3.7 vs. 17.0 ± 8.1 mmHg, p < 0.05) in CBDL rats. The mortality rate, mean arterial pressure, biochemistry data and hypoxia were similar between caffeine-treated and control groups. Caffeine alleviated liver fibrosis and intrahepatic angiogenesis but intrapulmonary inflammation and angiogenesis were not ameliorated. The hepatic VEGF/Rho-A protein expressions were down-regulated but the pulmonary inflammation- and angiogenesis-related protein expressions were not significantly altered by caffeine. Caffeine did not reduce the intrapulmonary shunting, either. Caffeine has been shown to significantly improve liver fibrosis, intrahepatic angiogenesis and portal hypertension in cirrhotic rats, however, it does not ameliorate HPS.

Association between appendectomy and risk of primary sclerosing cholangitis: A systematic review and meta-analysis

BACKGROUND/OBJECTIVES

Recent epidemiologic studies have suggested that appendectomy could be a risk factor for primary sclerosing cholangitis (PSC) although the results were inconsistent. This systematic review and meta-analysis was conducted to summarize all available evidence.

METHODS

A comprehensive literature review was conducted using MEDLINE and EMBASE database through January 2018 to identify all studies that reported the risk of PSC among individuals who had appendectomy versus those with no history of appendectomy. Effect estimates from each study were extracted and combined together using the random-effect, generic inverse variance method of DerSimonian and Laird.

RESULTS

A total of 6 case-control studies with 2432 participants met the eligibility criteria and were included in the meta-analysis. The risk of PSC in individuals who had appendectomy was significantly higher than those with no history of appendectomy with the pooled odds ratio of 1.37 (95% CI: 1.15-1.63). The statistical heterogeneity was insignificant with an I2 of 0%.

CONCLUSIONS

A significantly increased risk of PSC among individuals who had a history of appendectomy was found in this study.

Autoimmune liver disease and the enteric microbiome

The human enteric microbiome is highly complex and has more than 150 times more genes within it than its host. The host and the microbiome have a commensurate relationship that can evolve over time. The typically symbiotic relationship between the two can become pathogenic. The microbiome composition in adults reflects their history of exposure to bacteria and environmental factors during early life, their genetic background, age, interactions with the immune system, geographical location, and, most especially, their diet. Similarly, these factors are thought to contribute to the development of autoimmune disease. It is possible that alterations in the intestinal microbiome could lead to liver disease. There is emerging data for the contribution of the microbiome in development of primary sclerosing cholangitis, primary biliary cholangitis, and autoimmune hepatitis; liver disorders associated with aberrant immune function in genetically susceptible individuals.

Leveraging Social Networking Sites for an Autoimmune Hepatitis Genetic Repository: Pilot Study to Evaluate Feasibility

Background

Conventional approaches to participant recruitment are often inadequate in rare disease investigation. Social networking sites such as Facebook may provide a vehicle to circumvent common research limitations and pitfalls. We report our preliminary experience with Facebook-based methodology for participant recruitment and participation into an ongoing study of autoimmune hepatitis (AIH).

Objective

The goal of our research was to conduct a pilot study to assess whether a Facebook-based methodology is capable of recruiting geographically widespread participants into AIH patient-oriented research and obtaining quality phenotypic data.

Methods

We established a Facebook community, the Autoimmune Hepatitis Research Network (AHRN), in 2014 to provide a secure and reputable distillation of current literature and AIH research opportunities. Quarterly advertisements for our ongoing observational AIH study were posted on the AHRN over 2 years. Interested and self-reported AIH participants were subsequently enrolled after review of study materials and completion of an informed consent by our study coordinator. Participants returned completed study materials, including epidemiologic questionnaires and genetic material, to our facility via mail. Outside medical records were obtained and reviewed by a study physician.

Results

We successfully obtained all study materials from 29 participants with self-reported AIH within 2 years from 20 different states. Liver biopsy results were available for 90% (26/29) of participants, of which 81% (21/29) had findings consistent with AIH, 15% (4/29) were suggestive of AIH with features of primary biliary cholangitis (PBC), and 4% (1/29) had PBC alone. A total of 83% (24/29) had at least 2 of 3 proposed criteria: positive autoimmune markers, consistent histologic findings of AIH on liver biopsy, and reported treatment with immunosuppressant medications. Self-reported and physician records were discrepant for immunosuppressant medications or for AIH/PBC diagnoses in 4 patients.

Conclusions

Facebook can be an effective ancillary tool for facilitating patient-oriented research in rare diseases. A social media-based approach transcends established limitations in rare disease research and can further develop research communities.

Coffee and autoimmunity: More than a mere hot beverage!

Coffee is one of the world's most consumed beverage. In the last decades, coffee consumption has attracted a huge body of research due to its impact on health. Recent scientific evidences showed that coffee intake could be associated with decreased mortality from cardiovascular and neurological diseases, diabetes type II, as well as from endometrial and liver cancer, among others. In this review, on the basis of available data in the literature, we aimed to investigate the association between coffee intake and its influence on the immune system and the insurgence of the most relevant autoimmune diseases. While some studies reported conflicting results, general trends have been identified. Coffee consumption seems to increase the risk of developing rheumatoid arthritis (RA) and type 1 diabetes mellitus (T1DM). By contrast, coffee consumption may exert a protective role against multiple sclerosis, primary sclerosing cholangitis, and ulcerative colitis. Concerning other autoimmune diseases such as systemic lupus erythematosus, psoriasis, primary biliary cholangitis and Crohn's disease, no significant association was found. In other studies, coffee consumption was shown to influence disease course and management options. Coffee intake led to a decrease in insulin sensitivity in T1DM, in methotrexate efficacy in RA, and in levothyroxine absorption in Hashimoto's disease. Further, coffee consumption was associated with cross reactivity with gliadin antibodies in celiac patients. Data on certain autoimmune diseases like systemic sclerosis, Sjögren's syndrome, and Behçet's disease, among others, are lacking in the existent literature. As such, further research is warranted.

Epigenetics in the Primary Biliary Cholangitis and Primary Sclerosing Cholangitis

Epigenomics, the study of modifications to genetic material that do not alter the underlying DNA sequence, is generating increasing interest as a means to help clarify disease pathogenesis and outcomes. Although genome-wide association studies have identified several potential candidate genes that may be implicated in primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC), it is estimated that these genes explain less than 20% of the heritability of these diseases. Thus, to date, the origins of “missing heritability” for PBC and PSC remain elusive. The epigenome may provide a potentially elegant solution to this phenomenon, as it can be modified by both internal and external exposures (coined the “exposome”). This may explain differences in disease presentation, treatment response, and rates of progression between individuals. Epigenetic changes may also provide a framework for discovering potential biomarkers for diagnosis and screening of PBC and PSC. Importantly, because the epigenome is modifiable, it may also highlight novel pathways for therapeutic discovery and interventions of these diseases.

Coffee consumption protects against progression in liver cirrhosis and increases long-term survival after liver transplantation

BACKGROUND

Therapeutic options to treat progression of end-stage liver disease (ESLD) or improve long-term survival after liver transplantation remain scarce. We investigated the impact of coffee consumption under these conditions.

METHODS

We recorded coffee consumption habits of 379 patients with ESLD awaiting liver transplantation and 260 patients after liver transplantation. Survival was analyzed based on coffee intake.

RESULTS

One hundred ninety-five patients with ESLD consumed coffee on a daily basis, while 184 patients did not. Actuarial survival was impaired (P = 0.041) in non-coffee drinkers (40.4 ± 4.3 months, 95% confidence interval [CI]: 32.0-48.9) compared with coffee drinkers (54.9 ± 5.5 months, 95% CI: 44.0-65.7). In subgroup analysis, the survival of patients with alcoholic liver disease (ALD; P = 0.020) and primary sclerosing cholangitis (PSC; P = 0.017) was increased with coffee intake while unaffected in patients with chronic viral hepatitis (P = 0.517) or other liver disease entities (P = 0.652). Multivariate analysis showed that coffee consumption of PSC and ALD patients retained as an independent risk factor (odds ratio [OR]: 1.94; 95% CI: 1.15-3.28; P = 0.013) along with MELD score (OR: 1.13; 95% CI: 1.09-1.17; P = 0.000). Following liver transplantation, long-term survival was longer in coffee drinkers (coffee: 61.8 ± 2.0 months, 95% CI: 57.9-65.8) than non-drinkers (52.3 ± 3.5 months, 95% CI: 45.4-59.3; P = 0.001).

CONCLUSIONS

Coffee consumption delayed disease progression in ALD and PSC patients with ESLD and increased long-term survival after liver transplantation. We conclude that regular coffee intake might be recommended for these patients.

The Autoimmune Ecology

Autoimmune diseases (ADs) represent a heterogeneous group of disorders that affect specific target organs or multiple organ systems. These conditions share common immunopathogenic mechanisms (i.e., the autoimmune tautology), which explain the clinical similarities they have among them as well as their familial clustering (i.e., coaggregation). As part of the autoimmune tautology, the influence of environmental exposure on the risk of developing ADs is paramount (i.e., the autoimmune ecology). In fact, environment, more than genetics, shapes immune system. Autoimmune ecology is akin to exposome, that is all the exposures - internal and external - across the lifespan, interacting with hereditary factors (both genetics and epigenetics) to favor or protect against autoimmunity and its outcomes. Herein, we provide an overview of the autoimmune ecology, focusing on the immune response to environmental agents in general, and microbiota, cigarette smoking, alcohol and coffee consumption, socioeconomic status (SES), gender and sex hormones, vitamin D, organic solvents, and vaccines in particular. Inclusion of the autoimmune ecology in disease etiology and health will improve the way personalized medicine is currently conceived and applied.

Coffee and Caffeine Are Associated With Decreased Risk of Advanced Hepatic Fibrosis Among Patients With Hepatitis C

BACKGROUND & AIMS

Coffee or caffeine has been proposed to protect against hepatic fibrosis, but few data are available on their effects in patients with chronic hepatitis C virus (HCV) infection.

METHODS

We conducted a cross-sectional study of veterans with chronic HCV infection to evaluate the association between daily intake of caffeinated and decaffeinated coffee, tea, and soda, and level of hepatic fibrosis, based on the FibroSURE test (BioPredictive, Paris, France) (F0-F3, mild [controls] vs. F3/F4-F4, advanced). Models were adjusted for multiple potential confounders including age, alcohol abuse, and obesity.

RESULTS

Among 910 patients with chronic HCV infection, 98% were male and 38% had advanced hepatic fibrosis. Daily intake of caffeinated coffee was higher among controls than patients with advanced fibrosis (1.37 vs. 1.05 cups/d; P = .038). In contrast, daily intake of caffeinated tea (0.61 vs. 0.56 cups/d; P = .651) or soda (1.14 vs. 0.95 cans/d; P = .106) did not differ between the groups. A higher percentage of controls (66.0%) than patients with advanced fibrosis (57.9%) consumed 100 mg or more of caffeine daily from all sources (P = .014); controls also received a larger proportion of their caffeine from coffee (50.2% vs. 43.0%; P = .035). Hepatoprotective effects of an average daily intake of 100 mg or more of caffeine (adjusted odds ratio, 0.71; 95% confidence interval, 0.53-0.95; P = .020) and 1 cup or more of caffeinated tea by non-coffee drinkers (adjusted odds ratio, 0.56; 95% confidence interval, 0.34-0.94; P = .028) persisted after adjustment for confounders, including insulin resistance.

CONCLUSIONS

A modest daily caffeine intake (as little as 100 mg) may protect against advanced hepatic fibrosis in men with chronic HCV infection. Additional research is needed to confirm these findings in women and in people with other chronic liver diseases.

Primary sclerosing cholangitis: a clinical update

INTRODUCTION

Primary sclerosing cholangitis (PSC) is a progressive cholestatic disorder that ultimately can lead to cirrhosis, liver failure, malignancy and death. It is strongly associated with inflammatory bowel disease (IBD), and though a rare disease, its incidence is increasing. There are no proven medical therapies for PSC.

SOURCES OF DATA

Ovid Medline was utilised to search for articles with keywords 'sclerosing cholangitis' and 'cholangiocarcinoma' and containing titles 'primary sclerosing cholangitis', and references of these papers were cross-referenced for further relevant manuscripts.

AREAS OF AGREEMENT

PSC is a rare disease, and there is a strong association with risk loci within the major histocompatibility complex and other genes common to other autoimmune diseases. PSC is a premalignant condition, associated with higher rates of hepatobiliary and colorectal cancer in patients with ulcerative colitis (UC).

AREAS OF CONTROVERSY

The pathogenesis is unclear, and competing theories exist surrounding toxic bile acids, enhanced homing of particular T cells from the gut to the liver and increased passage of toxins to the liver through a permeable bowel wall. It is unclear whether the higher rate of colonic cancer in PSC/UC occurs in PSC/Crohn's disease. Ursodeoxycholic acid therapy reduces liver enzymes but has not been shown to improve survival. It may reduce the prevalence of bowel cancer.

GROWING POINTS

Recent genetic studies have revealed new risk loci, pointing to the importance of the immune system and its interaction with the biome.

AREAS TIMELY FOR DEVELOPING RESEARCH

On the basis of the genetic studies discussed earlier, novel agents are being developed and trialled in the treatment of PSC.

A comprehensive assessment of environmental exposures among 1000 North American patients with primary sclerosing cholangitis, with and without inflammatory bowel disease

BACKGROUND

The relationships between primary sclerosing cholangitis (PSC) and the environment are largely unknown.

AIM

To validate associations reported in previous studies and to identify novel environmental exposures among PSC patients.

METHODS

We performed a multicenter, case-control analysis utilising self-administered questionnaires. Responses between cases (n = 1000) and controls (n = 663) were compared using multivariable logistic regression adjusted for age and gender. The model was further stratified based on inflammatory bowel disease (IBD) status (with IBD n = 741 without IBD n = 259).

RESULTS

Smoking was associated with PSC only when IBD was present (OR, 0.5; 95% CI 0.4-0.7) but not among those PSC patients without IBD (OR, 0.9; 95% CI 0.7-1.2). Compared to controls, women with PSC (irrespective of the presence of IBD) were less likely to have received hormone replacement therapy (HRT; OR, 0.5; 95% CI 0.4-0.7) and were more likely to have recurrent urinary tract infections (OR, 1.6; 95% CI 1.2-2.3). PSC patients regardless of gender or IBD status were less likely to eat fish (OR, 0.4; 95% CI 0.3-0.6) and grilled/barbecued meat (OR, 0.8; 95% CI 0.7-0.9). In contrast, PSC patients with and without IBD were more likely to consume steak/burgers that were more well done (OR, 1.3; 95% CI 1.2-1.5).

CONCLUSIONS

IBD (rather than PSC) is associated with smoking. Women with PSC are more likely to have recurrent urinary tract infections and less likely to receive HRT. Dietary intake and methods of food preparation differ in PSC patients when compared to controls.