Treatment response and clinical event-free survival in autoimmune hepatitis: A Canadian multicentre cohort study.

BACKGROUND & AIMS: Treatment outcomes for people living with autoimmune hepatitis (AIH) are limited by a lack of specific therapies, as well as limited well-validated prognostic tools and clinical trial endpoints. We sought to identify predictors of outcome for people living with AIH. METHODS: We evaluated the clinical course of people with AIH across 11 Canadian centres. Biochemical changes were analysed using linear mixed-effect and logistic regression. Clinical outcome was dynamically modelled using time-varying Cox proportional hazard modelling and landmark analysis. RESULTS: In 691 patients (median age 49 years, 75.4% female), with a median follow-up of 6 years (25th-75th percentile, 2.5-11), 118 clinical events occurred. Alanine aminotransferase (ALT) normalisation occurred in 63.8% of the cohort by 12 months. Older age at diagnosis (odd ratio [OR] 1.19, 95% CI 1.06-1.35) and female sex (OR 1.94, 95% CI 1.18-3.19) were associated with ALT normalisation at 6 months, whilst baseline cirrhosis status was associated with reduced chance of normalisation at 12 months (OR 0.52, 95% CI 0.33-0.82). Baseline total bilirubin, aminotransferases, and IgG values, as well as initial prednisone dose, did not predict average ALT reduction. At baseline, older age (hazard ratio [HR] 1.25, 95% CI 1.12-1.40), cirrhosis at diagnosis (HR 3.67, 95% CI 2.48-5.43), and elevated baseline total bilirubin (HR 1.36, 95% CI 1.17-1.58) increased the risk of clinical events. Prolonged elevations in ALT (HR 1.07, 95% CI 1.00-1.13) and aspartate aminotransferase (HR 1.13, 95% CI 1.06-1.21), but not IgG (HR 1.01, 95% CI 0.95-1.07), were associated with higher risk of clinical events. Higher ALT at 6 months was associated with worse clinical event-free survival. CONCLUSION: In people living with AIH, sustained elevated aminotransferase values, but not IgG, are associated with poorer long-term outcomes. Biochemical response and long-term survival are not associated with starting prednisone dose. IMPACT AND IMPLICATIONS: Using clinical data from multiple Canadian liver clinics treating autoimmune hepatitis (AIH), we evaluate treatment response and clinical outcomes. For the first time, we apply mixed-effect and time-varying survival statistical methods to rigorously examine treatment response and the impact of fluctuating liver biochemistry on clinical event-free survival. Key to the study impact, our data is 'real-world', represents a diverse population across Canada, and uses continuous measurements over follow-up. Our results challenge the role of IgG as a marker of treatment response and if normalisation of IgG should remain an important part of the definition of biochemical remission. Our analysis further highlights that baseline markers of disease severity may not prognosticate early treatment response. Additionally, the initial prednisone dose may be less relevant for achieving aminotransferase normalisation. This is important for patients and treating clinicians given the relevance and importance of side effects.

Ethnicity, disease severity, and survival in Canadian patients with primary biliary cholangitis.

BACKGROUND AND AIMS: We investigated associations between ethnicity, survival, and disease severity in a diverse Canadian cohort of patients with primary biliary cholangitis (PBC). APPROACH AND RESULTS: Patients with PBC were included from the Canadian Network for Autoimmune Liver Disease. Ethnicity was defined using a modified list adopted from Statistics Canada, and ethnicities with small samples were grouped. Clinical events were defined as liver decompensation, HCC, liver transplantation, or death. Clinical event-free and liver transplantation-free survival were analyzed using Cox regression. Trajectories of serum liver function tests were assessed over time using mixed-effects regression. Health-related quality of life was assessed using the Short Form 36, the PBC-40 questionnaire, and the 5-D Itch scale and analyzed using mixed-effects regression. The cohort included 1538 patients with PBC from six sites and was comprised of 82% White, 4.7% Indigenous, 5.5% East Asian, 2.6% South Asian, and 5.1% miscellaneous ethnicities. Indigenous patients were the only ethnic group with impaired liver transplant-free and event-free survival compared to White patients (HR, 3.66; 95% CI, 2.23-6.01; HR, 3.09; 95% CI, 1.94-4.92). Indigenous patients were more likely to have a clinical event before diagnosis (10%) than all other ethnic groups despite similar age at diagnosis. Indigenous patients presented with higher alkaline phosphatase, total bilirubin, and GLOBE scores than White patients; and these relative elevations persisted during follow-up. CONCLUSIONS: Indigenous Canadians with PBC present with advanced disease and have worse long-term outcomes compared to White patients.

An Update to the Kaiser Permanente Inpatient Risk Adjustment Methodology Accurately Predicts In-Hospital Mortality: a Retrospective Cohort Study.

BACKGROUND: Methods to accurately predict the risk of in-hospital mortality are important for applications including quality assessment of healthcare institutions and research. OBJECTIVE: To update and validate the Kaiser Permanente inpatient risk adjustment methodology (KP method) to predict in-hospital mortality, using open-source tools to measure comorbidity and diagnosis groups, and removing troponin which is difficult to standardize across modern clinical assays. DESIGN: Retrospective cohort study using electronic health record data from GEMINI. GEMINI is a research collaborative that collects administrative and clinical data from hospital information systems. PARTICIPANTS: Adult general medicine inpatients at 28 hospitals in Ontario, Canada, between April 2010 and December 2022. MAIN MEASURES: The outcome was in-hospital mortality, modeled by diagnosis group using 56 logistic regressions. We compared models with and without troponin as an input to the laboratory-based acute physiology score. We fit and validated the updated method using internal-external cross-validation at 28 hospitals from April 2015 to December 2022. KEY RESULTS: In 938,103 hospitalizations with 7.2% in-hospital mortality, the updated KP method accurately predicted the risk of mortality. The c-statistic at the median hospital was 0.866 (see Fig. 3) (25th-75th 0.848-0.876, range 0.816-0.927) and calibration was strong for nearly all patients at all hospitals. The 95th percentile absolute difference between predicted and observed probabilities was 0.038 at the median hospital (25th-75th 0.024-0.057, range 0.006-0.118). Model performance was very similar with and without troponin in a subset of 7 hospitals, and performance was similar with and without troponin for patients hospitalized for heart failure and acute myocardial infarction. CONCLUSIONS: An update to the KP method accurately predicted in-hospital mortality for general medicine inpatients in 28 hospitals in Ontario, Canada. This updated method can be implemented in a wider range of settings using common open-source tools.

Real-world use of glucocorticoids and clinical outcomes in adults hospitalized with community-acquired pneumonia on medical wards.

BACKGROUND: Little is known about the real-world use of systemic glucocorticoids to treat patients hospitalized with community-acquired pneumonia (CAP) outside of the intensive care unit (ICU). METHODS: This retrospective cohort study included 11,588 hospitalizations for CAP without chronic pulmonary disease at seven hospitals in Ontario, Canada. We report physician-level variation in the use of glucocorticoids and trends over time. We investigated the association between glucocorticoid prescriptions and clinical outcomes, using propensity score overlap weighting to account for confounding by indication. RESULTS: Glucocorticoids were prescribed in 1283 (11.1%) patients, increasing over time from 10.0% in 2010 to 11.9% in 2020 (p = .008). Physician glucocorticoid prescribing ranged from 2.9% to 34.6% (median 10.0%, inter quartile range [IQR]: 6.7%-14.6%). Patients receiving glucocorticoids tended to be younger (median age 73 vs. 79), have higher Charlson comorbidity scores (score of 2 or more: 42.4% vs. 31.0%), more cancer (26.6% vs. 13.2%), more renal disease (11.5% vs. 6.6%), and less dementia (7.8% vs. 14.8%). Patients treated with glucocorticoids had higher rates of in-hospital mortality (weighted Risk Difference = 1.72, 95% confidence interval [95% CI]: 0.16-3.3, p = .033). Glucocorticoid use was not associated with ICU admission, hospital length-of-stay, or 30-day readmission. CONCLUSION: Glucocorticoids were prescribed in 11.1% of patients hospitalized with CAP outside of ICU and one in four physicians prescribed glucocorticoids in more than 14% of patients. Glucocorticoid use was associated with greater in-hospital mortality, although these findings are limited by large selection effects. Clinicians should exercise caution in prescribing glucocorticoids for nonsevere CAP, and definitive trials are needed in this population.

Development and external validation of tools for categorizing diagnosis codes in international hospital data.

BACKGROUND: The Clinical Classification Software Refined (CCSR) is a tool that groups many thousands of International Classification of Diseases 10th Revision (ICD-10) diagnosis codes into approximately 500 clinically meaningful categories, simplifying analyses. However, CCSR was developed for use in the United States and may not work well with other country-specific ICD-10 coding systems. METHOD: We developed an algorithm for semi-automated matching of Canadian ICD-10 codes (ICD-10-CA) to CCSR categories using discharge diagnoses from adult admissions at 7 hospitals between Apr 1, 2010 and Dec 31, 2020, and manually validated the results. We then externally validated our approach using inpatient hospital encounters in Denmark from 2017 to 2018. KEY RESULTS: There were 383,972 Canadian hospital admissions with 5,186 distinct ICD-10-CA diagnosis codes and 1,855,837 Danish encounters with 4,612 ICD-10 diagnosis codes. Only 46.6% of Canadian codes and 49.4% of Danish codes could be directly categorized using the official CCSR tool. Our algorithm facilitated the mapping of 98.5% of all Canadian codes and 97.7% of Danish codes. Validation of our algorithm by clinicians demonstrated excellent accuracy (97.1% and 97.0% in Canadian and Danish data, respectively). Without our algorithm, many common conditions did not match directly to a CCSR category, such as 96.6% of hospital admissions for heart failure. CONCLUSION: The GEMINI CCSR matching algorithm (available as an open-source package at https://github.com/GEMINI-Medicine/gemini-ccsr) improves the categorization of Canadian and Danish ICD-10 codes into clinically coherent categories compared to the original CCSR tool. We expect this approach to generalize well to other countries and enable a wide range of research and quality measurement applications.

Analysis of Resident and Attending Physician End-of-Rotation Changeover Days and Association With Patient Length of Stay.

Importance: End-of-rotation resident physician changeover is a key part of postgraduate training but could lead to discontinuity in patient care. Objective: To test whether patients exposed to end-of-rotation resident changeover have longer hospital stays and whether this association is mitigated by separating resident and attending changeover days. Design, Setting, and Participants: This retrospective cohort analysis included adult patients admitted to general internal medicine. The changeover day was the same day (first Monday of month) for both resident and attending physicians until June 30, 2013 (preseparation period), and then intentionally staggered by 1 or more days after July 1, 2013 (postseparation period). This was a multicenter analysis at 4 teaching hospitals in Ontario, Canada, from July 1, 2010, to June 30, 2019. Data analysis was conducted from July 2022 to January 2023. Exposures: Patients were classified as changeover patients if the first Monday was a resident changeover day and as control patients if the first Monday was not a resident changeover day. Main Outcomes and Measures: The primary outcome was length of hospital stay. Secondary outcomes were transfer to critical care, in-hospital death, and rate of discharge per 100 patients on the index day. Results: Of 95 282 patients. 22 773 (24%; mean [SD] age, 67.8 [18.8] years; 11 156 [49%] female patients) were exposed to resident changeover, and 72 509 (76%; mean [SD] age, 67.8 [18.7] years; 35 293 [49%] female patients) were not exposed to resident changeover. Exposure to resident changeover day was associated with a slightly longer hospital stay compared with control days (0.20 [95% CI, 0.09-0.30] days; P < .001) and decreased relative risk of patient discharge on the index day (relative risk, 0.92; 95% CI, 0.86-1.00; P = .047). These associations were similar in the preseparation and postseparation periods. Resident changeover was not associated with an increased risk of transfer to critical care or in-hospital death. Conclusions and Relevance: In this study, a small positive association between exposure to resident physician changeover and length of hospital stay as well as reduced rate of discharge was found. These findings suggest that separating changeover days for resident and attending physicians may not significantly change these associations.

Internal medicine hospitalisations and liver disease: a comparative disease burden analysis of a multicentre cohort.

BACKGROUND: Liver disease is an increasing burden on population health globally. AIMS: To characterise burden of liver disease among general internal medicine inpatients at seven Toronto-area hospitals and compare it to other common medical conditions. METHODS: Data from April 2010 to October 2017 were obtained from hospitals participating in the GEMINI collaborative. Using these cohort data from hospital information systems linked to administrative data, we defined liver disease admissions using most responsible discharge diagnoses categorised according to international classification of diseases, 10th Revision-enhanced Canadian version (ICD-10-CA). We identified admissions for heart failure, chronic obstructive pulmonary disease (COPD) and pneumonia as comparators. We calculated standardised mortality ratios (SMRs) as the ratio of observed to expected deaths. RESULTS: Among 239 018 discharges, liver disease accounted for 1.7% of most responsible discharge diagnoses. Liver disease was associated with marked premature mortality, with SMR of 8.84 (95% CI 8.06-9.67) compared to 1.06 (95% CI 0.99-1.12) for heart failure, 1.05 (95% CI 0.96-1.15) for COPD and 1.28 (95% CI 1.20-1.37) for pneumonia. The majority of deaths were among patients younger than 65 years (57.7%) compared to 3.3% in heart failure, 5.6% in COPD and 10.7% in pneumonia. Liver disease patients presented with worse Laboratory-Based Acute Physiology Scores, were more frequently admitted to the intensive care unit (14.4%), incurred higher average total costs (median $6723 CAD), had higher in-hospital mortality (11.4%), and were more likely to be a readmission from 30 days prior (19.8%). Non-alcoholic fatty liver disease admissions increased from 120 in 2011-2012 to 215 in 2016-2017 (P < 0.01). CONCLUSION: In Canada's largest urban centre, liver disease admissions resulted in premature morbidity and mortality with higher resource use compared to common cardio-respiratory conditions. Re-evaluation of approaches to caring for inpatients with liver disease is timely and justified.

Real-World Effectiveness of Obeticholic Acid in Patients with Primary Biliary Cholangitis.

Patients with primary biliary cholangitis (PBC) with incomplete response to ursodeoxycholic acid are at risk of disease progression and need additional therapy. Obeticholic acid (OCA) was approved in Canada in May 2017, but its effectiveness in a real-world setting has not been described. We sought to describe our experience with OCA in a Canadian cohort. OCA-naive patients treated at two Canadian centers were included. Clinical and biochemical data were collected at OCA initiation and during follow-up. Primary outcomes were changes in serum alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), and total bilirubin (TB) over the duration of therapy. Secondary outcomes were changes in alanine aminotransferase (ALT), aspartate aminotransferase (AST), immunoglobulin M (IgM), platelets, and albumin; and achievement of the primary endpoint of the original phase 3 study that led to OCA approval (A Placebo-Controlled Trial of Obeticholic Acid in Primary Biliary Cholangitis [POISE]), dose reductions, discontinuations, and tolerability. Repeated-measures models were used to assess changes in biochemistry over time. Sixty-four patients were included; 4 carried a diagnosis of overlap with autoimmune hepatitis. Mean age was 54.6 years, median ALP was 250 U/L, TB was 13 µmol/L, platelet count was 225 × 109/L, and 24% had liver stiffness measurements ≥16.9 kPa. There was a significant reduction in mean ALP of 55 U/L (P < 0.001), GGT of 138 U/L (P < 0.001), ALT of 11.9 U/L (P < 0.001), AST of 5.7 U/L (P < 0.05), and IgM of 0.70 g/L (P < 0.001) over 12 months; TB remained stable (P = 0.98). Forty-four patients met POISE-inclusion criteria, 39% (n = 17) of whom had 12-month biochemical measurements. In this subset, 18% (n = 3/17) met the 12-month POISE primary endpoint, but considering follow-up to 19 months, 43% achieved this target (n = 9/21). Pruritus was the most commonly reported complaint. Conclusion: Use of OCA was associated with improvement in biochemical surrogates of outcome in PBC in a real-world setting.