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Crowther, Mark Andrew

0000-0003-4986-4873

Mayo Clinic

McMaster University

Citations 7

The 2023 ACR / EULAR Antiphospholipid Syndrome Classification Criteria
Barbhaiya, Medha , Zuily, Stéphane , Naden, Ray, Hendry, Alison , Manneville, Florian , Amigo, Mary‐Carmen , Amoura, Zahir , Andréoli, Laura , Artım-Esen, Bahar , Atsumi, Tatsuya , Avčin, Tadej , Branch, D. Ware , Carvalheiras, Graziela , Cohen, Hannah , Jesús, Guilherme Ramires de , Desai, Sheetal , Sancho, Maria De, Küçükkaya, Reyhan Diz , Françès, Camille, García, David , Jordan, Natasha, Leaf, Rebecca Karp , Kello, Nina , Laskin, Carl A. , Lee, Alfred Ian , Legault, Kimberly, Levine, Steve, Limper, Maarten , Lockshin, Michael D. , Mayer-Pickel, K , Musial, Jack, Orsolini, Giovanni , Ortel, Thomas L. , Petri, Michelle , Gómez‐Puerta, José A. , Raimboug, Quentin, Roubey, Robert, Seshan, Surya V. , Tektonidou, Maria G. , Wahl, Denis , Willis, Rohan , Zuily, Catherine, Costenbader, Karen H. , Erkan, Doruk , Collaborators, the ACR/EULAR APS Classification Criteria, Andreoli, Laura , Avcin, Tadej , de Jesus, Guilherme , Duarte-García, Alí , Petri, Michelle , Pons-Estel, Guillermo , Gomez-Puerta, Jose A , Sciascia, Savino , Tektonidou, Maria G , Yelnik, Cecile , Costenbader, Karen , Erkan, Doruk , Cohen, Hannah , Andrade, Danieli , Belmont, H. Michael , Bertolaccini, Maria Laura , Casini, Alessandro , Cervera, Ricard , Costedoat-Chalumeau, Nathalie , Crowther, Mark Andrew , Delluc, Aurélien , Devreese, Katrien M.J. , Duarte‐García, Alí , Françès, C. , Gris, Jean‐Christophe , Knight, Jason S , Levy, Roger A. , Meroni, PierLuigi , Pengo, Vittorio , Pons‐Estel, Guillermo , Sanna, Giovanni , Sciascia, Savino , Tincani, Anǵela , Guillemin, Francis , Collaborators, the ACR/EULAR APS Classification Criteria

Arthritis & Rheumatology | August 28, 2023 | Volume: 75 | Issue: 10 | Pages: 1687-1702

10.1002/art.42624 Get It

Objective To develop new antiphospholipid syndrome (APS) classification criteria with high specificity for use in observational studies and trials, jointly supported by the American College of Rheumatology (ACR) and EULAR. Methods This international multidisciplinary initiative included 4 phases: 1) Phase I, criteria generation by surveys and literature review; 2) Phase II, criteria reduction by modified Delphi and nominal group technique exercises; 3) Phase III, criteria definition, further reduction with the guidance of real‐world patient scenarios, and weighting via consensus‐based multicriteria decision analysis, and threshold identification; and 4) Phase IV, validation using independent adjudicators’ consensus as the gold standard. Results The 2023 ACR/EULAR APS classification criteria include an entry criterion of at least one positive antiphospholipid antibody (aPL) test within 3 years of identification of an aPL‐associated clinical criterion, followed by additive weighted criteria (score range 1–7 points each) clustered into 6 clinical domains (macrovascular venous thromboembolism, macrovascular arterial thrombosis, microvascular, obstetric, cardiac valve, and hematologic) and 2 laboratory domains (lupus anticoagulant functional coagulation assays, and solid‐phase enzyme‐linked immunosorbent assays for IgG/IgM anticardiolipin and/or IgG/IgM anti–β 2 ‐glycoprotein I antibodies). Patients accumulating at least 3 points each from the clinical and laboratory domains are classified as having APS. In the validation cohort, the new APS criteria versus the 2006 revised Sapporo classification criteria had a specificity of 99% versu s 86%, and a sensitivity of 84% versus 99%. Conclusion These new ACR/EULAR APS classification criteria were developed using rigorous methodology with multidisciplinary international input. Hierarchically clustered, weighted, and risk‐stratified criteria reflect the current thinking about APS, providing high specificity and a strong foundation for future APS research.
The Khorana Score for the Prediction of Venous Thromboembolism in Patients with Solid Cancer: An Individual Patient Data Meta-Analysis
Ventresca, Matthew, García, David , Macbeth, Fergus , Brożek, Jan , Streiff, Michael B. , Flórez, Iván D. , Solh, Ziad , Bozas, George , Lebeau, B, Loprinzi, Charles L. , Bleker, Suzanne M. , Büller, Harry R. , Schünemann, Holger J. , Zulian, Gilbert B., Schünemann, Holger J , Es, Nick van , Zhou, Qi Xin , Noble, Simon , Crowther, Mark Andrew , Briel, Matthias , Lyman, Gary H , Griffiths, Gareth , Iorio, Alfonso , Mbuagbaw, Lawrence , Neumann, Ignacio , Guyatt, Gordon , Ageno, Walter , Marcucci, Maura , Maraveyas, Anthony , Lecumberri, Ramón , Sideras, Kostandinos , McBane, Robert D. , Pelzer, Uwe , Akl, Elie A. , Bossuyt, Patrick M. , Kahale, Lara A

Blood | April 6, 2021 | Volume: 130 | Issue: Suppl_1 | Pages: 627-627

10.1182/blood.v130.suppl_1.627.627 Get It

Abstract Background: Guidelines suggest the use of the Khorana score to select patients with solid cancer receiving chemotherapy for thromboprophylaxis to prevent venous thromboembolism (VTE), but its performance in different types of cancers remains uncertain. Methods: The present analysis includes individual patient data from seven randomized controlled trials that had compared prophylactic (ultra)-low-molecular-weight heparin (LMWH) with placebo or observation in patients with solid cancer. The analysis addresses the performance of the continuous and dichotomized Khorana score in predicting the 6-month risk of VTE in the trial control groups, overall and in types of cancer studies, as well as the efficacy and safety of LMWH among patients with a high-risk Khorana score. Random effects meta-analysis provided the basis for summary estimates. Findings: In the 3,403 patients from the control groups included in the analyses, the mean age was 61 years, 59% were male, and 58% had lung cancer. During 6-months of follow-up, 188 patients (5.5%) developed VTE. Overall, the 6-month VTE incidence was 9.8% among high-risk Khorana score patients and 6.4% among low-to-intermediate risk patients (OR 1.6; 95%-CI 1.1-2.2). The dichotomous Khorana score performed differently in lung cancer patients (OR 1.1; 95%-CI, 0.72-1.7) than in those with other types of cancer (OR 4.4; 95%-CI, 2.7-7.3; P interaction=0.002). Among high-risk patients, LMWH decreased the risk of VTE by 64% compared to placebo or observation (OR 0.36; 95%-CI, 0.22-0.58). In the group of patients with types of cancer other than lung cancer and a high-risk Khorana score (N=619), the 6-month VTE incidence was 3.3% (95% CI, 1.4 to 7.7) among LMWH recipients and 13% (95% CI, 6.8 to 24) among those not receiving LMWH (OR 0.23, 95% CI, 0.11 to 0.46; P <0.001). There was no difference in major bleeding (OR 1.2, 95% CI, 0.56 to 2.5). Interpretation: The Khorana score performs poorly in differentiating between those at high and low risk of VTE in patients with lung cancer, but is associated with a 4-fold increased risk of VTE in those with other types of cancer. Thromboprophylaxis is effective and safe in patients with a high-risk Khorana score. Funding: Canadian Institutes of Health Research knowledge synthesis grant, KRS 126594 Registration: International Prospective Register for Systematic Reviews (PROSPERO), CRD42013003526. Disclosures Van Es: Pfizer: Employment, Other: Comment: Dr. van Es reports personal fees from Pfizer as a member of their advisory board. These fees are unrelated to this project.. Crowther: Alexion: Speakers Bureau; Bayer: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Boehringer Ingelheim: Speakers Bureau; Leo Pharma: Research Funding; Pfizer: Honoraria; Portola: Consultancy; Shinogi: Consultancy. Macbeth: Cancer Research UK: Research Funding; Pfizer: Other: Provision of Dalteparin for FRAGMATIC trial. Griffiths: Pfizer: Consultancy, Other: Comment: I run an academic clinical trials unit, have received educational/investigator intiated research grants from companies that make these heparin agents. As consultant > 3 years ago, advised Pfizer on clinical trial designs unrelated to this study., Research Funding. Streiff: Roche: Research Funding; Portola: Research Funding; Janssen Scientific Affairs, LLC: Consultancy, Research Funding; CSL Behring: Consultancy, Research Funding. Ageno: Daiichi Sankyo: Consultancy, Honoraria; Bayer AG: Consultancy, Honoraria, Research Funding; BMS-Pfizer: Consultancy, Honoraria; Boehringer Ingelheim: Consultancy, Honoraria. Bozas: PharmaMar: Honoraria. Maraveyas: Bayer: Other: Personal fees and conference attendance; Bristol-Myers Squibb: Other: Grants and personal fees; Leo Pharma: Other: Grants, personal fees and conference attendance; Pfizer: Other: Personal fees. Loprinzi: Bristol Myers: Other: Grant - unrelated to this project; Janssen: Other: Grant - unrelated to this project. McBane: Bristol Myers Squibb: Other: Research grant for cancer associated VTE. Schünemann: Canadian Institutes of Health Research: Research Funding.
An Individual Participant Data Meta-Analysis of 13 Randomized Trials to Evaluate the Impact of Prophylactic Use of Heparin in Oncological Patients
Schünemann, Holger J. , Ventresca, Matthew, Nisio, Marcello Di , Macbeth, Fergus , García, David , Brożek, Jan , Streiff, Michael B. , Flórez, Iván D. , Solh, Ziad , Bleker, Suzanne M. , Bozas, George , Büller, Harry R. , Klerk, Clara, Lebeau, B, Loprinzi, Charles L. , Zulian, Gilbert B., Schünemann, Holger J , Crowther, Mark Andrew , Briel, Matthias , Zhou, Qi Xin , Noble, Simon , Griffiths, Gareth , Lyman, Gary H , Iorio, Alfonso , Mbuagbaw, Lawrence , Neumann, Ignacio , Es, Nick van , Guyatt, Gordon , Brouwers, Melissa , Baldeh, Tejan , Marcucci, Maura , Ageno, Walter , Lecumberri, Ramón , McBane, Robert D. , Sideras, Kostandinos , Maraveyas, Anthony , Pelzer, Uwe , Bossuyt, Patrick M. , Kahale, Lara A , Akl, Elie A.

Blood | April 6, 2021 | Volume: 130 | Issue: Suppl_1 | Pages: 626-626

10.1182/blood.v130.suppl_1.626.626 Get It

Abstract Background: Parenteral anticoagulants may improve outcomes in patients with cancer by reducing the risk of venous thromboembolism (VTE) and through a direct anti-tumour effect. Study-level meta-analysis indicates a reduction in VTE and provide moderate certainty that a small survival benefit exists; it is unclear if patients with specific cancers benefit more or less. Utilizing data from randomized controlled trials (RCT), this individual participant data meta-analysis examines the impact of heparin on survival, VTE and major bleeding in oncological patients randomized to low-molecular weight heparin (LMWH) or no LMWH. Methods: We performed a comprehensive systematic search for all RCTS (last search date March 2017) and contacted authors and sponsors to obtain individual participant data of patients with solid cancers and no other indication for prophylactic or therapeutic anticoagulation. We utilized the GRADE approach to evaluate the certainty of evidence and produce an evidence profile. All analyses followed the intention-to-treat principle. We calculated the impact on mortality through multivariable hierarchical models with patient-level variables as fixed effects and a categorical trial variable as a random effect. We adjusted the analysis for age, cancer type and metastasis status. To investigate whether intervention effects vary by predefined subgroups, including type of cancer, we tested interaction terms in the statistical model. Results: A total of 18 RCTs (n=10,041 participants) were eligible for inclusion and we obtained data from 82.4% of the participants (13 RCTs, n=8,278; n=4,139 for LMWH and n=4,139 for no LMWH). The meta-analysis revealed an adjusted relative risk of mortality within one year of 0.99 (95% CI: 0.95, 1.03) and a hazard ratio of 0.97 (95% CI: 0.82, 1.14) after one year. The relative risk for VTE was 0.58 (95% CI: 0.48, 0.71), 0.57 (95% CI: 0.44, 0.74) for symptomatic deep vein thrombosis and 0.58 (95%CI: 0.44, 0.77) for symptomatic pulmonary embolism, separately. For every 1,000 patients treated, approximately 16 fewer would experience symptomatic DVT and 16 fewer would experience any PE. The adjusted relative risk for major bleeding throughout trial duration was 1.24 (95% CI: 0.91, 1.69; P=0.17). Subgroup analysis, by cancer type, of VTE occurrence throughout trial duration identified lung cancer OR=0.52 (95% CI: 0.39, 0.68; P<0.001) and pancreatic cancer OR=0.55 (95% CI: 0.35, 0.88; P=0.01) patients as experiencing the greatest benefit from LMWH treatment. The certainty of the evidence for the outcomes was moderate to high. Conclusion: LMWH reduces risk of VTE without increasing risk of bleeding but does not improve survival across all patients. Funding: Canadian Institutes of Health Research knowledge synthesis grant, KRS 126594 Registration: International Prospective Register for Systematic Reviews (PROSPERO), CRD42013003526. Disclosures Schünemann: Canadian Institutes of Health Research: Research Funding. Crowther: Alexion: Speakers Bureau; Bayer: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Boehringer Ingelheim: Speakers Bureau; Leo Pharma: Research Funding; Pfizer: Honoraria; Portola: Consultancy; Shinogi: Consultancy. Macbeth: Pfizer: Other: Provision of Dalteparin for FRAGMATIC trial; Cancer Research UK: Research Funding. Griffiths: Pfizer: Consultancy, Other: Comment: I run an academic clinical trials unit, have received educational/investigator intiated research grants from companies that make these heparin agents. As consultant > 3 years ago, advised Pfizer on clinical trial designs unrelated to this study., Research Funding. Van Es: Pfizer: Employment, Other: Comment: Dr. van Es reports personal fees from Pfizer as a member of their advisory board. These fees are unrelated to this project.. Streiff: Roche: Research Funding; Portola: Research Funding; Janssen Scientific Affairs, LLC: Consultancy, Research Funding; CSL Behring: Consultancy, Research Funding. Ageno: BMS-Pfizer: Consultancy, Honoraria; Bayer AG: Consultancy, Honoraria, Research Funding; Boehringer Ingelheim: Consultancy, Honoraria; Daiichi Sankyo: Consultancy, Honoraria. Bozas: PharmaMar: Honoraria. McBane: Bristol Myers Squibb: Other: Research grant for cancer associated VTE. Maraveyas: Bayer: Other: Personal fees and conference attendance; Bristol-Myers Squibb: Other: Grants and personal fees; Leo Pharma: Other: Grants, personal fees and conference attendance; Pfizer: Other: Personal fees. Loprinzi: Bristol Myers: Other: Grant - unrelated to this project; Janssen: Other: Grant - unrelated to this project.
Use of heparins in patients with cancer: individual participant data meta-analysis of randomised trials study protocol
Schünemann, Holger J. , Ventresca, Matthew, Briel, Matthias , García, David , Noble, Simon , Macbeth, Fergus , Griffiths, Gareth , DiNisio, Marcello, Iorio, Alfonso , Beyene, Joseph, Mbuagbaw, Lawrance, Es, Nick van , Brouwers, Melissa , Brożek, Jan , Levine, Mark N. , Moll, Stephan , Streiff, Michael B. , Baldeh, Tejan , Flórez, Iván D. , Alma, Özlem Gürünlü , Solh, Ziad , Ageno, Walter , Marcucci, Maura , Bozas, George , Zulian, Gilbert B., Lebeau, B, Büller, Harry R. , McBane, Robert D. , Bleker, Suzanne M. , Pelzer, Uwe , Iorio, Alfonso , Crowther, Mark Andrew , Zhou, Qi Xin , Lyman, Gary H , Neumann, Ignacio , Guyatt, Gordon , Santesso, Nancy A. , Maraveyas, Anthony , Evans, Jessica , Akl, Elie A. , McBane, Robert , Schünemann, Holger J , Ageno, Walter

BMJ Open | April 29, 2016 | Volume: 6 | Issue: 4 | Pages: e010569

10.1136/bmjopen-2015-010569 Get It

Introduction Parenteral anticoagulants may improve outcomes in patients with cancer by reducing risk of venous thromboembolic disease and through a direct antitumour effect. Study-level systematic reviews indicate a reduction in venous thromboembolism and provide moderate confidence that a small survival benefit exists. It remains unclear if any patient subgroups experience potential benefits. Methods and analysis First, we will perform a comprehensive systematic search of MEDLINE, EMBASE and The Cochrane Library, hand search scientific conference abstracts and check clinical trials registries for randomised control trials of participants with solid cancers who are administered parenteral anticoagulants. We anticipate identifying at least 15 trials, exceeding 9000 participants. Second, we will perform an individual participant data meta-analysis to explore the magnitude of survival benefit and address whether subgroups of patients are more likely to benefit from parenteral anticoagulants. All analyses will follow the intention-to-treat principle. For our primary outcome, mortality, we will use multivariable hierarchical models with patient-level variables as fixed effects and a categorical trial variable as a random effect. We will adjust analysis for important prognostic characteristics. To investigate whether intervention effects vary by predefined subgroups of patients, we will test interaction terms in the statistical model. Furthermore, we will develop a risk-prediction model for venous thromboembolism, with a focus on control patients of randomised trials. Ethics and dissemination Aside from maintaining participant anonymity, there are no major ethical concerns. This will be the first individual participant data meta-analysis addressing heparin use among patients with cancer and will directly influence recommendations in clinical practice guidelines. Major cancer guideline development organisations will use eventual results to inform their guideline recommendations. Several knowledge users will disseminate results through presentations at clinical rounds as well as national and international conferences. We will prepare an evidence brief and facilitate dialogue to engage policymakers and stakeholders in acting on findings. Trial registration number PROSPERO CRD42013003526.
The ASH Choosing Wisely® campaign: five hematologic tests and treatments to question
Hicks, Lisa K. , Bering, Harriet, Carson, Kenneth R. , Kleinerman, Judith, Kukreti, Vishal , Ma, Alice , Mueller, Brigitta U., O’Brien, Sarah H. , Pasquini, Marcelo C. , Haynes, Adam E., Hicks, Lisa K. , Sarode, Ravi , Solberg, Lawrence A. , Crowther, Mark Andrew

Hematology | December 6, 2013 | Volume: 2013 | Issue: 1 | Pages: 9-14

10.1182/asheducation-2013.1.9 Get It

Abstract Choosing Wisely® is a medical stewardship and quality improvement initiative led by the American Board of Internal Medicine Foundation in collaboration with leading medical societies in the United States. The ASH is an active participant in the Choosing Wisely® project. Using an iterative process and an evidence-based method, ASH has identified 5 tests and treatments that in some circumstances are not well supported by evidence and which in certain cases involve a risk of adverse events and financial costs with low likelihood of benefit. The ASH Choosing Wisely® recommendations focus on avoiding liberal RBC transfusion, avoiding thrombophilia testing in adults in the setting of transient major thrombosis risk factors, avoiding inferior vena cava filter usage except in specified circumstances, avoiding the use of plasma or prothrombin complex concentrate in the nonemergent reversal of vitamin K antagonists, and limiting routine computed tomography surveillance after curative-intent treatment of non-Hodgkin lymphoma. We recommend that clinicians carefully consider anticipated benefits of the identified tests and treatments before performing them.
The ASH Choosing Wisely® campaign: five hematologic tests and treatments to question
Hicks, Lisa K. , Bering, Harriet, Carson, Kenneth R. , Kleinerman, Judith, Kukreti, Vishal , Ma, Alice , Mueller, Brigitta U., O’Brien, Sarah H. , Pasquini, Marcelo C. , Solberg, Lawrence A. , Haynes, Adam E., Hicks, Lisa K. , Sarode, Ravi , Crowther, Mark Andrew

Blood | December 4, 2013 | Volume: 122 | Issue: 24 | Pages: 3879-3883

10.1182/blood-2013-07-518423 Get It

Abstract Choosing Wisely® is a medical stewardship and quality improvement initiative led by the American Board of Internal Medicine Foundation in collaboration with leading medical societies in the United States. The ASH is an active participant in the Choosing Wisely® project. Using an iterative process and an evidence-based method, ASH has identified 5 tests and treatments that in some circumstances are not well supported by evidence and which in certain cases involve a risk of adverse events and financial costs with low likelihood of benefit. The ASH Choosing Wisely® recommendations focus on avoiding liberal RBC transfusion, avoiding thrombophilia testing in adults in the setting of transient major thrombosis risk factors, avoiding inferior vena cava filter usage except in specified circumstances, avoiding the use of plasma or prothrombin complex concentrate in the nonemergent reversal of vitamin K antagonists, and limiting routine computed tomography surveillance after curative-intent treatment of non-Hodgkin lymphoma. We recommend that clinicians carefully consider anticipated benefits of the identified tests and treatments before performing them.
The American Society of Hematology 2011 evidence-based practice guideline for immune thrombocytopenia
Lim, Wendy , Cohen, Alan R. , Solberg, Lawrence A. , Neunert, Cindy E. , Crowther, Mark Andrew

Blood | February 16, 2011 | Volume: 117 | Issue: 16 | Pages: 4190-4207

10.1182/blood-2010-08-302984 Get It

Abstract Immune thrombocytopenia (ITP) is commonly encountered in clinical practice. In 1996 the American Society of Hematology published a landmark guidance paper designed to assist clinicians in the management of this disorder. Since 1996 there have been numerous advances in the management of both adult and pediatric ITP. These changes mandated an update in the guidelines. This guideline uses a rigorous, evidence-based approach to the location, interpretation, and presentation of the available evidence. We have endeavored to identify, abstract, and present all available methodologically rigorous data informing the treatment of ITP. We provide evidence-based treatment recommendations using the GRADE system in those areas in which such evidence exists. We do not provide evidence in those areas in which evidence is lacking, or is of lower quality—interested readers are referred to a number of recent, consensus-based recommendations for expert opinion in these clinical areas. Our review identified the need for additional studies in many key areas of the therapy of ITP such as comparative studies of “front-line” therapy for ITP, the management of serious bleeding in patients with ITP, and studies that will provide guidance about which therapy should be used as salvage therapy for patients after failure of a first-line intervention.