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Featured researches published by Willem J. Lammers.


Gut | 2016

Stratification of hepatocellular carcinoma risk in primary biliary cirrhosis: a multicentre international study

Palak J. Trivedi; Willem J. Lammers; Henk R. van Buuren; Albert Parés; Annarosa Floreani; Harry L.A. Janssen; Pietro Invernizzi; Pier Maria Battezzati; Cyriel Y. Ponsioen; Christophe Corpechot; Raoul Poupon; Marlyn J. Mayo; Andrew K. Burroughs; Frederik Nevens; Andrew L. Mason; Kris V. Kowdley; Ana Lleo; Llorenç Caballería; Keith D. Lindor; Bettina E. Hansen; Gideon M. Hirschfield

Objective Hepatocellular carcinoma (HCC) is an infrequent yet critical event in primary biliary cirrhosis (PBC); however, predictive tools remain ill-defined. Our objective was to identify candidate risk factors for HCC development in patients with PBC. Design Risk factor analysis was performed in over 15 centres from North America and Europe spanning >40 years observation period using Cox proportional hazards assumptions, logistic regression, and Kaplan-Meier estimates. Results Of 4565 patients with PBC 123 developed HCC, yielding an incidence rate (IR) of 3.4 cases/1000 patient-years. HCC was significantly more common in men (p<0.0001), and on univariate analysis factors at PBC diagnosis associated with future HCC development were male sex (unadjusted HR 2.91, p<0.0001), elevated serum aspartate transaminase (HR 1.24, p<0.0001), advanced disease (HR 2.72, p=0.022), thrombocytopenia (HR 1.65, p<0.0001), and hepatic decompensation (HR 9.89, p<0.0001). As such, non-treatment with ursodeoxycholic acid itself was not associated with cancer development; however, 12-month stratification by biochemical non-response (Paris-I criteria) associated significantly with future risk of HCC (HR 4.52, p<0.0001; IR 6.6 vs 1.4, p<0.0001). Non-response predicted future risk in patients with early stage disease (IR 4.7 vs 1.2, p=0.005), advanced disease (HR 2.79, p=0.02; IR 11.2 vs 4.4, p=0.033), and when restricting the analysis to only male patients (HR 4.44, p<0.001; IR 18.2 vs 5.4, p<0.001). On multivariable analysis biochemical non-response remained the most significant factor predictive of future HCC risk (adjusted HR 3.44, p<0.0001). Conclusions This uniquely powered, internationally representative cohort robustly demonstrates that 12-month biochemical non-response is associated with increased future risk of developing HCC in PBC. Such risk stratification is relevant to patient care and development of new therapies.


The American Journal of Gastroenterology | 2018

Major Hepatic Complications in Ursodeoxycholic Acid-Treated Patients With Primary Biliary Cholangitis: Risk Factors and Time Trends in Incidence and Outcome

Maren H. Harms; Willem J. Lammers; Douglas Thorburn; Christophe Corpechot; Pietro Invernizzi; Harry L.A. Janssen; Pier Maria Battezzati; Frederik Nevens; Keith D. Lindor; Annarosa Floreani; Cyriel Y. Ponsioen; Marlyn J. Mayo; George N. Dalekos; Tony Bruns; Albert Parés; Andrew L. Mason; Xavier Verhelst; Kris V. Kowdley; Jorn C Goet; Gideon M. Hirschfield; Bettina E. Hansen; Henk R. van Buuren

Objectives:In this era of near universal ursodeoxycholic acid (UDCA) treatment for primary biliary cholangitis (PBC), progression to cirrhosis still occurs in an important proportion of patients. The aim of this study was to describe the incidence of cirrhosis-associated complications in patients with PBC and assess risk factors and impact on survival.Methods:Cohorts of UDCA-treated patients from 16 European and North-American liver centers were included. We used Cox proportional hazards assumptions and Kaplan–Meier estimates.Results:During 8.1 years’ median follow-up, 278 of 3,224 patients developed ascites, variceal bleeding, and/or encephalopathy (incidence rate of 9.7 cases/1,000 patient years). The overall cumulative incidence was 9.1% after 10 years of follow-up, but decreased over time to 5.8% after the year 2000. Earlier calendar year of diagnosis (P<0.001), high aspartate aminotransferase to platelets ratio index (APRI; P<0.001) and biochemical non-response (P<0.001) were independently associated with future complications. Patients with both biochemical non-response and an APRI >0.54 after 12 months of UDCA had a 10-year complication rate of 37.4%, as compared to 3.2% in biochemical responders with an APRI ≤0.54. The 10-year transplantation-free survival after a complication was 9% (time-dependent hazard ratio 21.5; 20.1–22.8). Prognosis after variceal bleeding has improved over time.Conclusions:In this large international cohort, up to 15% of UDCA-treated PBC patients developed major non-neoplastic, cirrhosis-associated hepatic complications within 15 years, but cumulative incidence has decreased over time. Biochemical non-response to UDCA and APRI were independent risk factors for these complications. Subsequent long-term outcome after complications is generally poor, but has improved over the past decades.


Hepatology | 2018

Milder disease stage in patients with primary biliary cholangitis over a 44-year period : a changing natural history

Carla F. Murillo Perez; Jorn C Goet; Willem J. Lammers; Aliya Gulamhusein; Henk R. van Buuren; Cyriel Y. Ponsioen; Marco Carbone; Andrew L. Mason; Christophe Corpechot; Pietro Invernizzi; Marlyn J. Mayo; Pier Maria Battezzati; Annarosa Floreani; Albert Parés; Frederik Nevens; Kris V. Kowdley; Tony Bruns; George N. Dalekos; Douglas Thorburn; Gideon M. Hirschfield; Nicholas F. LaRusso; Keith D. Lindor; Kalliopi Zachou; Raoul Poupon; Palak J. Trivedi; Xavier Verhelst; Harry L.A. Janssen; Bettina E. Hansen

Changes over time in the presenting features and clinical course of patients with primary biliary cholangitis are poorly described. We sought to describe temporal trends in patient and disease characteristics over a 44‐year period across a large international primary biliary cholangitis cohort of 4,805 patients diagnosed between 1970 and 2014, from 17 centers across Europe and North America. Patients were divided into five cohorts according to their year of diagnosis: 1970‐1979 (n = 143), 1980‐1989 (n = 858), 1990‐1999 (n = 1,754), 2000‐2009 (n = 1,815), and ≥2010 (n = 235). Age at diagnosis, disease stage, response to ursodeoxycholic acid, and clinical outcomes were compared. Mean age at diagnosis increased incrementally by 2‐3 years per decade from 46.9 ± 10.1 years in the 1970s to 57.0 ± 12.1 years from 2010 onward (P < 0.001). The female to male ratio (9:1) and antimitochondrial antibody positivity (90%) were not significantly variable. The proportion of patients presenting with mild biochemical disease (according to Rotterdam staging) increased from 41.3% in the 1970s to 72.2% in the 1990s (P < 0.001) and remained relatively stable thereafter. Patients with a mild histological stage at diagnosis increased from 60.4% (1970‐1989) to 76.5% (1990‐2014) (P < 0.001). Correspondingly, response to ursodeoxycholic acid according to Paris‐I criteria increased; 51.7% in the 1970s and 70.5% in the 1990s (P < 0.001). Recent decades were also characterized by lower decompensation rates (18.5% in the 1970s to 5.8% in the 2000s, P < 0.001) and higher 10‐year transplant‐free survival (48.4%, 68.7%, 79.7%, and 80.1% for each respective cohort; P < 0.001). Conclusion: In recent decades, a pattern of primary biliary cholangitis presentation consistent with an older age at diagnosis alongside reduced disease severity has been noted; the observed trends may be explained by an increase in routine testing of liver function and/or a changing environmental trigger. (Hepatology 2018;67:1920‐1930).


Digestive Diseases | 2015

Surrogate Endpoints for Optimal Therapeutic Response to UDCA in Primary Biliary Cholangitis

Henk R. van Buuren; Willem J. Lammers; Maren H. Harms; Bettina E. Hansen

Background: Ursodeoxycholic acid (UDCA) is the standard treatment for primary biliary cholangitis (PBC), as it can delay histological progression, improve long-term outcome and is extremely safe and well tolerated. However, UDCA is not always sufficient and the prognosis of patients inadequately responding to treatment is worse compared with the general population. Reliable identification of so-called non-responders is of key importance, not only for selecting patients who could benefit from additional, second-line therapy, but also for identifying those individuals who are at low risk of developing end-stage disease and in whom UDCA mono-therapy can be safely continued. Several laboratory surrogate endpoints for the long-term response to UDCA have been proposed, including the Barcelona, Paris, Toronto and Rotterdam criteria. All these criteria have limitations and the superiority of one over the other has not been firmly established. Key Messages: Recently the Global PBC Study Group developed a new prognostic tool by studying a large, representative and multinational cohort of 4,119 UDCA-treated patients. In a random sample of 2,488 cases, a risk score - the GLOBE score - was developed, predictive of transplantation-free survival. This risk score comprises age, and bilirubin, albumin, alkaline phosphatase and platelet count obtained after 1 year therapy, and has a performance (C statistic 0.81, 95% CI 0.79-0.83) that is markedly better than that of previously proposed response criteria. Comparable performance was found in an independent validation cohort of 1,631 cases (C statistic 0.82, 95% CI 0.79-0.84). A web app will allow the easy use of the score in clinical practice.


Hepatology Communications | 2018

Clinical application of the GLOBE and United Kingdom‐primary biliary cholangitis risk scores in a trial cohort of patients with primary biliary cholangitis

Marco Carbone; Maren H. Harms; Willem J. Lammers; T. Marmon; Richard Pencek; Leigh MacConell; David Shapiro; David Jones; George F. Mells; Bettina E. Hansen

The GLOBAL Primary Biliary Cholangitis (PBC) Study Group and United Kingdom‐PBC (UK‐PBC) Consortium have demonstrated that dichotomous response criteria are not as accurate as continuous equations at predicting mortality or liver transplantation in PBC. The aim of this analysis was to assess the clinical utility of the GLOBE and UK‐PBC risk scores using data from POISE, a phase 3 trial investigating obeticholic acid (OCA) in patients with PBC. Data (N = 216) at baseline and month 12 were used to calculate the GLOBE and UK‐PBC risk scores to assess the projected change in risk with OCA versus placebo. Additionally, the benefit of OCA was assessed in patients not meeting the POISE primary endpoint. Both the GLOBE and UK‐PBC risk scores predicted a significant reduction in long‐term risk of death and liver transplantation after OCA treatment (P < 0.0001). The differences in the relative risk reduction from baseline in the 10‐year event risk after 1 year for OCA 10 mg versus placebo was 26% (GLOBE) and 37% (UK‐PBC). The scores also predicted a significantly decreased risk in patients treated with OCA who did not meet POISE response criteria after 1 year of treatment compared to an increased risk with placebo (P < 0.0001). Conclusion: This analysis demonstrates the use of the GLOBE and UK‐PBC risk scores to assess risk reduction of a cohort treated with OCA. While validation of this risk reduction in studies with clinical outcomes is needed, this study highlights the potential use of these scores in individualizing risk prediction in PBC both in clinical practice and therapeutic trials. (Hepatology Communications 2018;2:683‐692)


Gut | 2014

OC-030 Effective Stratification Of Hepatocellular Carcinoma Risk In Primary Biliary Cirrhosis: Results Of A Multi-centre International Study

Palak J. Trivedi; Willem J. Lammers; H.R. van Buuren; Harry L.A. Janssen; P. Invernizzi; Pier Maria Battezzati; Annarosa Floreani; Albert Parés; Cyriel Y. Ponsioen; Christophe Corpechot; Raoul Poupon; Marlyn J. Mayo; J. Talwalkar; Andrew K. Burroughs; Frederik Nevens; Andrew L. Mason; Tony Bruns; K.-K. Li; Kris V. Kowdley; Teru Kumagi; Angela C. Cheung; Ana Lleo; N Cazagon; I. Franceschet; Llorenç Caballería; Kirsten Boonstra; E. de Vries; Mohamad Imam; Giulia Pieri; Pushpjeet Kanwar

Introduction Hepatocellular carcinoma (HCC) is an important but infrequent outcome in primary biliary cirrhosis (PBC). Improved risk evaluation is an important goal for stratified surveillance. Methods Risk-factor analysis of the ‘Global PBC Study Group’ comprising 15 centres across North America and Europe spanning >40-years follow-up was performed using Cox proportional hazards model, logistic regression and Kaplan-Meier estimates (SPSSv21). Results Of 3546 patients with PBC (med. follow-up 8.6 yrs; IQR 4.4–14.1), 131 developed HCC. Excluding those who developed HCC within 12 months of PBC diagnosis (n = 23), median time to HCC was 12.7 yrs (6.9–16.8) and subsequent survival 1.1 yrs. (0.2–2.7). At diagnosis, factors associated with HCC development were male gender (adj. HR: 4.4;1.4–12.2, p = 0.014) and thrombocytopenia (adj. HR: 4.5;1.4–14.8, p = 0.012). Use of ursodeoxycholic acid per-se was not associated with future risk of HCC, but stratification of risk by biochemical response at 12 months was effective by Rotterdam (adj. HR: 8.9;2.1–37.3, P = 0.003), Paris-I (adj. HR: 7.6;2.0–29.0, p = 0.003) or Toronto criteria (HR: 5.6;1.6–18.8, P = 0.006). Five (4.6 vs. 0.2%) and 10-year (13%vs.1.9%) HCC incidence was significantly increased for biochemical non-responders (p = 2.2 × 10–9), and by multivariate analysis non-response remained the only significant risk factor. Conclusion Our uniquely powered cohort allows robust demonstration that 12-month biochemical non-response is associated with an increased risk of developing HCC in PBC. Routine surveillance in those achieving biochemical response is unlikely cost-effective. Disclosure of Interest None Declared.


Journal of Hepatology | 2013

941 ALKALINE PHOSPHATASE VALUES ARE A SURROGATE MARKER IN PREDICTION OF TRANSPLANT FREE SURVIVAL IN PATIENTS WITH PRIMARY BILIARY CIRRHOSIS – AN INTERNATIONAL, COLLABORATIVE ANALYSIS

Willem J. Lammers; H.R. van Buuren; Gideon M. Hirschfield; Albert Parés; Teru Kumagi; Llorenç Caballería; P. Invernizzi; Ana Lleo; Pier Maria Battezzati; Christophe Corpechot; Annarosa Floreani; N. Cazzagon; Marlyn J. Mayo; J. Talwalkar; Mohamad Imam; Andrew K. Burroughs; Giulia Pieri; Frederik Nevens; Andrew L. Mason; Raoul Poupon; H.L.A. Janssen; Keith D. Lindor; Bettina E. Hansen

941 ALKALINE PHOSPHATASE VALUES ARE A SURROGATE MARKER IN PREDICTION OF TRANSPLANT FREE SURVIVAL IN PATIENTS WITH PRIMARY BILIARY CIRRHOSIS – AN INTERNATIONAL, COLLABORATIVE ANALYSIS W.J. Lammers, H.R. van Buuren, G.M. Hirschfield, A. Pares, T. Kumagi, L. Caballeria, P. Invernizzi, A. Lleo, P.M. Battezzati, C. Corpechot, A. Floreani, N. Cazzagon, M.J. Mayo, J.A. Talwalkar, M. Imam, A.K. Burroughs, G. Pieri, F. Nevens, A.L. Mason, R. Poupon, H.L.A. Janssen, K.D. Lindor, B.E. Hansen, Global PBC Study Group. Gastroenterology and Hepatology, Erasmus MC University Medical Center, Rotterdam, The Netherlands; Liver Centre, Toronto Western Hospital, Toronto, ON, Canada; Centre for Liver Research and NIHR Institute of Biomedical Research, University of Birmingham, Birmingham, UK; Liver Unit, Hospital Cĺinic, CIBERehd, IDIBAPS, Barcelona, Spain; Center for Autoimmune Liver Diseases, Humanitas Clinical and Research Center, Rozzano, Italy; Dept of Medicine, Surgery and Dentistry, Universita degli Studi di Milano, Milan, Italy; Service d’Hepatologie, Hopital Saint-Antoine, APHP, UPMC, Paris, France; Department of Surgical, Oncological and Gastroenterological, University of Padova, Padova, Italy; Digestive and Liver disease, UT Southwestern Medical Centre, Dallas, TX, Gastroenterology and Hepatology, Mayo Clinic, Rochester, MA, USA; The Sheila Sherlock Liver Centre, The Royal Free Hospital, London, UK; Hepatology, University Hospitals Leuven, UKLeuven, Leuven, Belgium; Divison of Gastroenterology and Hepatology, University of Alberta, Edmonton, AB, Canada; Health Solutions, Arizona State University, Phoenix, AZ, USA E-mail: [email protected]


Gastroenterology | 2014

Levels of Alkaline Phosphatase and Bilirubin Are Surrogate End Points of Outcomes of Patients With Primary Biliary Cirrhosis: An International Follow-up Study

Willem J. Lammers; Henk R. van Buuren; Gideon M. Hirschfield; Harry L.A. Janssen; Pietro Invernizzi; Andrew L. Mason; Cyriel Y. Ponsioen; Annarosa Floreani; Christophe Corpechot; Marlyn J. Mayo; Pier Maria Battezzati; Albert Parés; Frederik Nevens; Andrew K. Burroughs; Kris V. Kowdley; Palak J. Trivedi; Teru Kumagi; Angela Cheung; Ana Lleo; Mohamad Imam; Kirsten Boonstra; N. Cazzagon; I. Franceschet; Raoul Poupon; Llorenç Caballería; Giulia Pieri; Pushpjeet Kanwar; Keith D. Lindor; Bettina E. Hansen


Gastroenterology | 2015

Development and Validation of a Scoring System to Predict Outcomes of Patients with Primary Biliary Cirrhosis Receiving Ursodeoxycholic Acid Therapy

Willem J. Lammers; Gideon M. Hirschfield; Christophe Corpechot; Frederik Nevens; Keith D. Lindor; Harry L.A. Janssen; Annarosa Floreani; Cyriel Y. Ponsioen; Marlyn J. Mayo; Pietro Invernizzi; Pier Maria Battezzati; Albert Parés; Andrew K. Burroughs; Andrew L. Mason; Kris V. Kowdley; Teru Kumagi; Maren H. Harms; Palak J. Trivedi; Raoul Poupon; Angela Cheung; Ana Lleo; Llorenç Caballería; Bettina E. Hansen; Henk R. van Buuren


Annals of Hepatology | 2014

Predicting outcome in primary biliary cirrhosis

Willem J. Lammers; Kris V. Kowdley; Henk R. van Buuren

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Bettina E. Hansen

Erasmus University Rotterdam

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Marlyn J. Mayo

University of Texas Southwestern Medical Center

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Frederik Nevens

Katholieke Universiteit Leuven

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