Craig Lammert

Relationship between daily dose of oral medications and idiosyncratic drug‐induced liver injury: Search for signals

Idiosyncratic drug‐induced liver injury (DILI) is traditionally thought not to be dose‐related. However, it has been pointed out that most medicines that were withdrawn from marketing or received a black‐box warning because of hepatotoxicity were prescribed at daily doses greater than 50 mg/day. To examine the relationship between daily dose of medications and idiosyncratic DILI, we conducted a study with two aims. First, using two pharmaceutical databases, we examined the relationship between daily dose of commonly prescribed medicines in the United States and reported frequency of their selected hepatic adverse events. Second, we examined serious DILI cases reported to the Swedish Adverse Drug Reactions Advisory Committee (1970‐2004) for any signals supporting the relationship between daily dose and idiosyncratic DILI. Medications were categorized into ≤10 mg/day, 11‐49 mg/day, and ≥50 mg/day groups. Among US prescription medicines, a statistically significant relationship was observed between daily dose of oral medicines and reports of liver failure (P = 0.009), liver transplantation (P < 0.001), and death caused by DILI (P = 0.004) but not alanine aminotransferase (ALT) > 3 × upper limit of normal (P = 0.10) or jaundice (P = 0.16). Of 598 eligible Swedish DILI cases, 9% belonged to the ≤10 mg/day group, 14.2% to the 11‐49 mg/day group, and 77% of cases were caused by medications given at dose ≥50 mg/day. A statistically significant relationship was noted between daily dose and poor outcome (death or liver transplantation) of Swedish DILI cases (2%, 9.4%, and 13.2% in ≤10, 11‐49, and ≥50 mg/day groups, respectively, P = 0.03). Conclusion: These data suggest a relationship between daily doses of oral prescription medications and idiosyncratic DILI. More studies are needed to validate these observations and to explore their implications. (HEPATOLOGY 2008.)

Oral medications with significant hepatic metabolism at higher risk for hepatic adverse events.

Reactive metabolites generated by hepatic metabolism are thought to play an important role in the pathogenesis of drug‐induced liver injury (DILI), but supporting data are limited. If this is true, then compounds with significant hepatic metabolism should cause more DILI than those without it. We conducted a study to examine the relationship between hepatic metabolism and DILI of prescription medications. We systematically extracted the metabolism characteristics of 207 of the most widely prescribed oral medications in the United States. Compounds with >50% hepatic metabolism were characterized as those with significant hepatic metabolism (n = 149). Hepatic adverse events of interest were alanine aminotransferase >3 times the upper limit of normal, jaundice, liver failure, liver transplantation, or fatal DILI. Compared with compounds with lesser hepatic metabolism, compounds belonging to the significant hepatic metabolism group had significantly higher frequency of alanine aminotransferase >3 times the upper limit of normal (35% versus 11%, P = 0.001), liver failure (28% versus 9%, P = 0.004), and fatal DILI (23% versus 4%, P = 0.001), but not jaundice (46% versus 35%, P = 0.2) or liver transplantation (9% versus 2%, P = 0.11). Twelve compounds with no hepatic metabolism had no reports of liver failure, liver transplantation, or fatal DILI. When the relationship between hepatic adverse events and combination of hepatic metabolism and daily dose was examined, compounds with both significant hepatic metabolism and daily dose >50 mg (n = 50) were significantly more hepatotoxic than compounds belonging to other groups. Compared with medications without biliary excretion, compounds with biliary excretion (n = 50) had significantly higher frequency of jaundice (74% versus 40%, P = 0.0001). Conclusion: Our study finds an important relationship between a compounds metabolism profile and reports of hepatic adverse events. (HEPATOLOGY 2009.)

Immunochip analyses identify a novel risk locus for primary biliary cirrhosis at 13q14, multiple independent associations at four established risk loci and epistasis between 1p31 and 7q32 risk variants

To further characterize the genetic basis of primary biliary cirrhosis (PBC), we genotyped 2426 PBC patients and 5731 unaffected controls from three independent cohorts using a single nucleotide polymorphism (SNP) array (Immunochip) enriched for autoimmune disease risk loci. Meta-analysis of the genotype data sets identified a novel disease-associated locus near the TNFSF11 gene at 13q14, provided evidence for association at six additional immune-related loci not previously implicated in PBC and confirmed associations at 19 of 22 established risk loci. Results of conditional analyses also provided evidence for multiple independent association signals at four risk loci, with haplotype analyses suggesting independent SNP effects at the 2q32 and 16p13 loci, but complex haplotype driven effects at the 3q25 and 6p21 loci. By imputing classical HLA alleles from this data set, four class II alleles independently contributing to the association signal from this region were identified. Imputation of genotypes at the non-HLA loci also provided additional associations, but none with stronger effects than the genotyped variants. An epistatic interaction between the IL12RB2 risk locus at 1p31and the IRF5 risk locus at 7q32 was also identified and suggests a complementary effect of these loci in predisposing to disease. These data expand the repertoire of genes with potential roles in PBC pathogenesis that need to be explored by follow-up biological studies.

Frequency, clinical presentation, and outcomes of drug-induced liver injury after liver transplantation†‡

Drug‐induced liver injury (DILI) is increasingly being recognized as a common cause of acute hepatitis. The clinical impact of DILI after liver transplantation (LT) is not known. The aim of this study was to describe the frequency, clinical presentation, and outcomes of DILI in LT recipients. LT recipients with possible DILI were identified with electronic pathology records and clinical note database retrieval tools. Diagnostic criteria were applied to identify cases of DILI. Twenty‐nine of 1689 LT recipients (1.7%) were identified with DILI. The mean age was 52 years, and 52% were women. The major indications for LT were primary sclerosing cholangitis (28%), cholangiocarcinoma (14%), and hepatocellular carcinoma (14%). The severity of DILI was mild or moderate in 92% of the cases. Nausea or diarrhea (31%), jaundice (24%), and pruritus (10%) were the most common symptoms at the time of diagnosis. The mean biochemistry values were as follows: alanine aminotransferase, 204 ± 263 U/L; aspartate aminotransferase, 108 ± 237 U/L; alkaline phosphatase, 469 ± 689 U/L; and total bilirubin, 1.9 ± 10.3 mg/dL. The median duration of medication use until the diagnosis of DILI was 57 days, and the major agent classes were antibiotics (48%), immunosuppressive agents (14%), and antihyperlipidemic drugs (7%). Trimethoprim‐sulfamethoxazole was the most common implicated agent (n = 11). Serum liver enzymes improved within a median time of 34 days (range = 5‐246 days) after drug withdrawal. Hepatic retransplantation or death did not occur. Among the 50 cases with possible DILI explained by other causes, 13 individuals (26%) had no alternative diagnosis despite histological findings compatible with DILI. In conclusion, DILI is a rare yet underrecognized event among LT recipients. The majority of cases are not clinically severe, and they resolve after drug cessation without hepatic retransplantation or death. Liver Transpl, 2012.

Questionnaire based assessment of risk factors for primary biliary cirrhosis

BACKGROUND Primary biliary cirrhosis is a cholestatic liver disease characterized by immune-mediated destruction of bile ducts. Its pathogenesis is largely unknown, although complex interactions between environment and genetic predisposition are proposed. AIMS Identify disease risk factors using a detailed patient questionnaire and compare study findings to 3 published reports. METHODS Questionnaire data were prospectively collected from 522 cases and 616 controls of the Mayo Clinic Primary Biliary Cirrhosis Genetic Epidemiology Registry. Case and control responses were compared using logistic regression, adjusting for recruitment age, sex, and education level. RESULTS Cases reported ever regularly smoking cigarettes more frequently than controls (P < 0.001). History of urinary tract infection was similar between groups; however, cases reported multiple urinary tract infections more commonly than controls (P < 0.001). Frequency of other autoimmune disease was higher in cases than controls (P < 0.001). As well, prevalence of primary biliary cirrhosis among first-degree relatives was higher in case families than control families (P < 0.001). CONCLUSIONS Our study confirms prior reported risk factors associated with disease risk. Given the potential importance of gene and environment interactions, further examination of environmental risk factors considering genetic background may provide new insight into primary biliary cirrhosis pathogenesis.

Reduced Coffee Consumption Among Individuals With Primary Sclerosing Cholangitis but Not Primary Biliary Cirrhosis

BACKGROUND & AIMS Coffee consumption has been associated with decreased risk of liver disease and related outcomes. However, coffee drinking has not been investigated among patients with cholestatic autoimmune liver diseases, primary biliary cirrhosis (PBC), or primary sclerosing cholangitis (PSC). We investigated the relationship between coffee consumption and risk of PBC and PSC in a large North American cohort. METHODS Lifetime coffee drinking habits were determined from responses to questionnaires from 606 patients with PBC, 480 with PSC, and 564 healthy volunteers (controls). Patients (those with PBC or PSC) were compared with controls by using the Wilcoxon rank sum test for continuous variables and c(2) method for discrete variables. Logistic regression was used to analyze the estimate of the effects of different coffee parameters (time, frequency, and type of coffee consumption) after adjusting for age, sex, smoking status, and education level. RESULTS Patients with PBC and controls did not differ in coffee parameters. However, 24% of patients with PSC had never drunk coffee compared with 16% of controls (P < .05), and only 67% were current drinkers compared with 77% of controls (P < .05). Patients with PSC also consumed fewer lifetime cups per month (45 vs 47 for controls, P < .05) and spent a smaller percentage of their lifetime drinking coffee (46.6% vs 66.7% for controls, P < .05). These differences remained significant in a multivariate model. Among PSC patients with concurrent ulcerative colitis, coffee protected against proctocolectomy (hazard ratio, 0.34; P < .001). CONCLUSIONS Coffee consumption is lower among patients with PSC, but not PBC, compared with controls.

Investigation Gone Viral: Application of the Social Mediasphere in Research

The research paradigm in the United States remains burdened by numerous obstacles impeding the progress of scientific investigation.1 Barriers to effective and efficient conduct of academic research include growing costs, delayed results, adequate staffing, and regulatory encumbrances.2–5 Beyond these system constraints, patient recruitment in research studies can be time-intensive, costly, and limited by minimal participant diversity.6,7 The social mediasphere, an intertwining universe of online social media applications, may represent a new model in research methodology that will bridge current research challenges in all medical fields. Investigators and study staff will require a fundamental appreciation of social media structure, existing methodology, and advantages and limitations in order to effectively conduct research with this novel strategy.

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.

Management of Autoimmune Hepatitis Patients Refractory to or Intolerant of Standard Therapies

Purpose of ReviewAutoimmune hepatitis is a progressive T cell-dependent inflammatory process characterized by elevated autoantibodies, serum globulins, and interface hepatitis. Pharmacologic treatment focuses on achievement of complete biochemical remission. The goal of this paper is to describe the unique features that guide treatment in difficult-to-control cases of autoimmune hepatitis.Recent FindingsRecently published retrospective reviews have noted the efficacy of multiple second- and third-line agents in the treatment of autoimmune hepatitis. There has been no widely accepted approach regarding which agents to use in specific patient populations.SummaryThis paper attempts to summarize recent evidence regarding treatment efficacy of second- and third-line therapies and addresses patient-specific considerations when deciding which therapies to choose.

Extrahepatic Autoimmune Diseases are Prevalent in Autoimmune Hepatitis Patients and their First-Degree Relatives (Preprint)

Background Concurrent autoimmune illnesses contribute to increased medical burden and reduced quality of life in patients with autoimmune hepatitis (AIH). The frequency of coexisting autoimmune conditions among North American patients with AIH and their families remains incomplete. Challenges associated with disease capture in the electronic medical record, high study costs, and geographic spread of patients are formidable barriers to understanding the extent of concurrent autoimmune conditions in these groups. Objective This objective of this study was to examine the frequency of extrahepatic autoimmune diseases (EHAD) among AIH cases and healthy controls as well as their first-degree relatives using social networking sites (SNS). Methods We developed a 53-question survey detailing the history of autoimmune diseases. A survey link was posted at routine intervals within specific Web-based cohorts on SNS. Healthy controls, without self-reported autoimmune liver disease, were recruited from Amazon’s Mechanical Turk. Continuous variables were summarized using medians and P values obtained with the Wilcoxon rank-sum test. Categorical variables were compared using the chi-square test. Results Compared with controls (n=1162), cases (n=306) were more likely to be older (median age: 49 vs 33 years), female (284/306, 92.81% vs 955/1162, 82.18%), and have an EHAD (128/306, 41.83% vs 218/1162, 18.76%; P=.001). The most frequent EHADs among cases were thyroid disease (49/306, 16.01% ), Sjögren syndrome (27/306, 8.82%), Raynaud phenomenon (23/306, 7.52%), and psoriasis (22/306, 7.19%). Overall, 55.88% (171/306) of cases and 35.71% (1601/4484) of controls reported at least 1 first-degree relative (FDR) with a history of EHAD (P=.001). Cases had a significantly higher risk of EHAD than controls after the adjustment for age, sex, race, and body mass index: odds ratio 2.46 (95% CI 1.8-3.3); P=.001. Conclusions Patients with AIH report higher prevalence of coexistent EHAD than healthy controls, and their FDRs are also more likely to have autoimmune disorders.