8 results on '"Laura Diekman"'
Search Results
2. A multiple imputation method based on weighted quantile regression models for longitudinal censored biomarker data with missing values at early visits
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MinJae Lee, Mohammad H. Rahbar, Matthew Brown, Lianne Gensler, Michael Weisman, Laura Diekman, and John D. Reveille
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Limit of detection ,Left-censoring ,Missing early visits ,Quantile regression ,Multiple imputation ,Medicine (General) ,R5-920 - Abstract
Abstract Background In patient-based studies, biomarker data are often subject to left censoring due to the detection limits, or to incomplete sample or data collection. In the context of longitudinal regression analysis, inappropriate handling of these issues could lead to biased parameter estimates. We developed a specific multiple imputation (MI) strategy based on weighted censored quantile regression (CQR) that not only accounts for censoring, but also missing data at early visits when longitudinal biomarker data are modeled as a covariate. Methods We assessed through simulation studies the performances of developed imputation approach by considering various scenarios of covariance structures of longitudinal data and levels of censoring. We also illustrated the application of the proposed method to the Prospective Study of Outcomes in Ankylosing spondylitis (AS) (PSOAS) data to address the issues of censored or missing C-reactive protein (CRP) level at early visits for a group of patients. Results Our findings from simulation studies indicated that the proposed method performs better than other MI methods by having a higher relative efficiency. We also found that our approach is not sensitive to the choice of covariance structure as compared to other methods that assume normality of biomarker data. The analysis results of PSOAS data from the imputed CRP levels based on our method suggested that higher CRP is significantly associated with radiographic damage, while those from other methods did not result in a significant association. Conclusion The MI based on weighted CQR offers a more valid statistical approach to evaluate a biomarker of disease in the presence of both issues with censoring and missing data in early visits.
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- 2018
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3. The changing profile of ankylosing spondylitis in the biologic era
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John D. Reveille, Mark C. Hwang, Mohammad H. Rahbar, Thomas J. Learch, MinJae Lee, Lianne S. Gensler, Michael M. Ward, Laura Diekman, Amirali Tahanan, Michael H. Weisman, and Mariko L. Ishimori
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Ankylosing spondylitis ,medicine.medical_specialty ,business.industry ,Disease progression ,General Medicine ,Disease ,medicine.disease ,Rheumatology ,Pharmacotherapy ,Internal medicine ,Medicine ,Disease characteristics ,Longitudinal cohort ,business - Abstract
To compare disease characteristics, comorbidities, and medication utilization of 1141 patients with ankylosing spondylitis (AS) with short ( 8 years. Patients with AS enrolling in this multicenter longitudinal cohort have different disease profiles and medication utilization over time, perhaps reflecting innovations in treatment and increasing disease awareness.
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- 2020
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4. Polygenic Risk Scores have high diagnostic capacity in ankylosing spondylitis
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Matthew A. Brown, Laura Diekman, Maxime Breban, Nicholas G. Martin, Yuqin Wang, Erika De Guzman, Paul Leo, Zhixiu Li, Gary J. Macfarlane, Lisa Anderson, Simon Stebbings, Margaret J. Wright, Michael M. Ward, Gareth T. Jones, Mahdi Mahmoudi, Mohammad H. Rahbar, Zi-Bing Jin, Jing Song, Huji Xu, MinJae Lee, Mengmeng Li, Xiaobing Wang, Michael H. Weisman, Andrew A. Harrison, Nurullah Akkoc, Jian Zhan, B P Wordsworth, Lianne S. Gensler, So Young Bang, Li Lin, Xin Wu, Elham Farhadi, James Cheng-Chung Wei, John D. Reveille, Helena Marzo-Ortega, Lawrie Wheeler, Chung Tei Chou, Geng Wang, Jin San Zhang, Tae-Hwan Kim, Ahmadreza Jamshidi, Queensland University of Technology [Brisbane] (QUT), Manisa Celal Bayar University, Université de Versailles Saint-Quentin-en-Yvelines - UFR Sciences de la santé Simone Veil (UVSQ Santé), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Infection et inflammation (2I), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut National de la Santé et de la Recherche Médicale (INSERM), Service de Rhumatologie, Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpital Ambroise Paré [AP-HP], Université Paris Diderot, Sorbonne Paris Cité, Paris, France, Université Paris Diderot - Paris 7 (UPD7), University of Aberdeen, Tehran University of Medical Sciences (TUMS), University of Leeds, National Yang Ming University (NYMU), University of Otago [Dunedin, Nouvelle-Zélande], Hanyang University, University of Queensland [Brisbane], QIMR Berghofer Medical Research Institute, Queensland Brain Institute, University of Texas Southwestern Medical Center [Dallas], Griffith University [Brisbane], Beijing Tongren Hospital, University of California [San Francisco] (UCSF), University of California, National Institutes of Health [Bethesda] (NIH), The University of Texas Health Science Center at Houston (UTHealth), University of Oxford [Oxford], ANR-10-MIDI-0002,GEMISA,GEnétique, Microbiote, Inflammation, et Spondylarthrite Ankylosante(2010), Second Military Medical University [Shanghai], Hôpital Ambroise Paré [AP-HP], Laboratoire d'Excellence INFLAMEX [Paris], Université Sorbonne Paris Cité (USPC), Leeds Teaching Hospitals NHS Trust, Taipei Veterans General Hospital [Taiwan], Chung Shan Medical University, China Medical University, Wenzhou Medical University [Wenzhou, China] (WMU), The First Affiliated Hospital of Wenzhou Medical University [Wenzhou, China], Wenzhou University [Wenzhou, China], Cedars-Sinai Medical Center, Tsinghua University [Beijing] (THU), King‘s College London, and TCRI AS Group: Jian Yin, Lei Jiang, Lin Zhou, Ting Li, Qingwen Wang, Tianwang Li, Guanmin Gao, Shengqian Xu, Weiguo Xiao, Hui Shen, Jingguo Zhou, Yuquan You, Dongbao Zhao, Qing Cai, Shengming Dai, Lan He, Ping Zhu, Zhenyu Jiang, Jian Xu, Huaxiang Wu, Lie Dai, Yang Li, Feng Ding, Xiaochun Zhu, Chongyang Liu, Dongyi He, Liyun Zhang, Zhijun Li, Futao Zhao, Hanshi Xu, Niansong Wang, Youlian Wang, Lindi Jiang, Yu Zhang, Jinwei Chen, Fang Cheng, Zhiyi Zhang, Yifang Mei, Liangjing Lv, Lingli Dong, Jing Yang, Yinong Li, Xiaodong Wang, Xiaofeng Li, Hongsheng Sun, Xianming Long, Xiao Zhang, Qinghong Yu, Xiaodan Kong, Yi Zheng, Miaojia Zhang, Yi Tao, Yisha Li, Xinwang Duan, Qianghua Wei, Xiaofei Wang, Jie Han, Rong Mu, Yiping Lin, Jian Zhu, Xiaoyuan Chen
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0301 basic medicine ,medicine.medical_specialty ,[SDV]Life Sciences [q-bio] ,Immunology ,General Biochemistry, Genetics and Molecular Biology ,polymorphism ,03 medical and health sciences ,0302 clinical medicine ,Rheumatology ,Internal medicine ,medicine ,Back pain ,magnetic resonance imaging ,Immunology and Allergy ,Spondylitis ,low back pain ,030203 arthritis & rheumatology ,HLA-B27 ,Ankylosing spondylitis ,[SDV.GEN.GPO]Life Sciences [q-bio]/Genetics/Populations and Evolution [q-bio.PE] ,Receiver operating characteristic ,business.industry ,Area under the curve ,spondylitis ,medicine.disease ,Low back pain ,ankylosing ,030104 developmental biology ,[SDV.MHEP.RSOA]Life Sciences [q-bio]/Human health and pathology/Rhumatology and musculoskeletal system ,[SDV.GEN.GH]Life Sciences [q-bio]/Genetics/Human genetics ,genetic ,medicine.symptom ,business - Abstract
ObjectiveWe sought to test the hypothesis that Polygenic Risk Scores (PRSs) have strong capacity to discriminate cases of ankylosing spondylitis (AS) from healthy controls and individuals in the community with chronic back pain.MethodsPRSs were developed and validated in individuals of European and East Asian ethnicity, using data from genome-wide association studies in 15 585 AS cases and 20 452 controls. The discriminatory values of PRSs in these populations were compared with other widely used diagnostic tests, including C-reactive protein (CRP), HLA-B27 and sacroiliac MRI.ResultsIn people of European descent, PRS had high discriminatory capacity with area under the curve (AUC) in receiver operator characteristic analysis of 0.924. This was significantly better than for HLA-B27 testing alone (AUC=0.869), MRI (AUC=0.885) or C-reactive protein (AUC=0.700). PRS developed and validated in individuals of East Asian descent performed similarly (AUC=0.948). Assuming a prior probability of AS of 10% such as in patients with chronic back pain under 45 years of age, compared with HLA-B27 testing alone, PRS provides higher positive values for 35% of patients and negative predictive values for 67.5% of patients. For PRS, in people of European descent, the maximum positive predictive value was 78.2% and negative predictive value was 100%, whereas for HLA-B27, these values were 51.9% and 97.9%, respectively.ConclusionsPRS have higher discriminatory capacity for AS than CRP, sacroiliac MRI or HLA-B27 status alone. For optimal performance, PRS should be developed for use in the specific ethnic groups to which they are to be applied.
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- 2021
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5. Harmonization, data management, and statistical issues related to prospective multicenter studies in Ankylosing spondylitis (AS): Experience from the Prospective Study Of Ankylosing Spondylitis (PSOAS) cohort
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Amirali Tahanan, MinJae Lee, Thomas J. Learch, Mohammad H. Rahbar, John D. Reveille, Matthew A. Brown, Michael H. Weisman, Manouchehr Hessabi, and Laura Diekman
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medicine.medical_specialty ,Electronic data capture ,Data management ,PSOAS cohort ,Article ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Bone formation ,Statistical analysis ,030212 general & internal medicine ,Prospective cohort study ,030203 arthritis & rheumatology ,Pharmacology ,Ankylosing spondylitis ,lcsh:R5-920 ,business.industry ,Data quality ,General Medicine ,medicine.disease ,3. Good health ,Harmonization ,Cohort ,Physical therapy ,Reliability of data ,business ,lcsh:Medicine (General) - Abstract
Ankylosing spondylitis (AS) is characterized by inflammation of the spine and sacroiliac joints causing pain and stiffness and, in some patients, ultimately new bone formation, and progressive joint ankyloses. The classical definition of AS is based on the modified New York (mNY) criteria. Limited data have been reported regarding data quality assurance procedure for multicenter or multisite prospective cohort of patients with AS. Since 2002, 1272 qualified AS patients have been enrolled from five sites (4 US sites and 1 Australian site) in the Prospective Study Of Ankylosing Spondylitis (PSOAS). In 2012, a Data Management and Statistical Core (DMSC) was added to the PSOAS team to assist in study design, establish a systematic approach to data management and data quality, and develop and apply appropriate statistical analysis of data. With assistance from the PSOAS investigators, DMSC modified Case Report Forms and developed database in Research Electronic Data Capture (REDCap). DMSC also developed additional data quality assurance procedure to assure data quality. The error rate for various forms in PSOAS databases ranged from 0.07% for medications data to 1.1% for arthritis activity questionnaire-Global pain. Furthermore, based on data from a sub study of 48 patients with AS, we showed a strong level (90.0%) of agreement between the two readers of X-rays with respect to modified Stoke Ankylosing Spondylitis Spine Score (mSASSS). This paper not only could serve as reference for future publications from PSOAS cohort but also could serve as a basic guide to ensuring data quality for multicenter clinical studies. Keywords: Ankylosing spondylitis, Data quality, Harmonization, PSOAS cohort, Reliability of data
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- 2018
6. Ethnicity and disease severity in ankylosing spondylitis a cross-sectional analysis of three ethnic groups
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Thomas J. Learch, Lianne S. Gensler, Michael H. Weisman, Laura Diekman, Matthew A. Brown, Shervin Assassi, MinJae Lee, Mohammad H. Rahbar, John D. Reveille, Amirali Tahanan, Farokh Jamalyaria, and Michael M. Ward
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Male ,Cross-sectional study ,medicine.medical_treatment ,Ethnic group ,Severity of Illness Index ,0302 clinical medicine ,Longitudinal Studies ,Prospective Studies ,030212 general & internal medicine ,Prospective cohort study ,HLA-B27 Antigen ,African Continental Ancestry Group ,African Americans ,medicine.diagnostic_test ,Hispanic or Latino ,General Medicine ,Middle Aged ,Blacks ,TNF inhibitor ,Erythrocyte sedimentation rate ,Disease Progression ,Female ,Hispanic Americans ,Ankylosing spondylitis ,Ankylosing ,Adult ,medicine.medical_specialty ,European Continental Ancestry Group ,Clinical Sciences ,Black People ,Blood Sedimentation ,Autoimmune Disease ,White People ,Article ,Young Adult ,03 medical and health sciences ,Rheumatology ,Internal medicine ,medicine ,Humans ,Spondylitis, Ankylosing ,Latinos ,Disease severity ,030203 arthritis & rheumatology ,HLA-B27 ,Whites ,business.industry ,Arthritis ,Reproducibility of Results ,medicine.disease ,Spine ,Arthritis & Rheumatology ,Black or African American ,Cross-Sectional Studies ,Physical therapy ,business ,Spondylitis - Abstract
The purpose of this study is to compare disease severity in ankylosing spondylitis (AS) in three ethnic groups. We assessed 925 AS patients (57 Blacks, 805 Whites, 63 Latinos) enrolled in the longitudinal Prospective Study of Outcomes in AS (PSOAS) for functional impairment, disease activity, and radiographic severity. Comparisons of clinical characteristics and HLA-B27 frequency for each group were performed, in two multivariable regression models, we compared the baseline Bath Ankylosing Spondylitis Radiographic Index (BASRI) and modified Stokes Ankylosing Spondylitis Spine Score (mSASSS) by ethnicity, adjusting for covariates. Blacks had greater functional impairment (Bath Ankylosing Spondylitis Functional Index) (median 62.5 vs. 27.8 in Whites and 38.1 in Latinos; p 
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- 2017
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7. Opioid Analgesic Use in Patients with Ankylosing Spondylitis: An Analysis of the Prospective Study of Outcomes in an Ankylosing Spondylitis Cohort
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MinJae Lee, Mohammad H. Rahbar, Jonathan D. Dau, Laura Diekman, Lianne S. Gensler, Michael M. Ward, Matthew A. Brown, Michael H. Weisman, John D. Reveille, Amirali Tahanan, and Thomas J. Learch
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Male ,OPIOID ,Severity of Illness Index ,Disability Evaluation ,0302 clinical medicine ,Risk Factors ,Immunology and Allergy ,030212 general & internal medicine ,Longitudinal Studies ,Prospective Studies ,Prospective cohort study ,BASDAI ,Analgesics ,medicine.diagnostic_test ,Depression ,Statistics ,Pain Research ,PAIN ,Middle Aged ,Analgesics, Opioid ,Mental Health ,C-Reactive Protein ,Treatment Outcome ,Erythrocyte sedimentation rate ,Cohort ,Public Health and Health Services ,Female ,Chronic Pain ,medicine.drug ,Cohort study ,Ankylosing ,Adult ,medicine.medical_specialty ,Clinical Sciences ,Immunology ,Blood Sedimentation ,Statistics, Nonparametric ,Article ,03 medical and health sciences ,Rheumatology ,Clinical Research ,Internal medicine ,medicine ,Humans ,Nonparametric ,Spondylitis, Ankylosing ,Aged ,030203 arthritis & rheumatology ,Ankylosing spondylitis ,Chi-Square Distribution ,business.industry ,COHORT STUDIES ,ANKYLOSING SPONDYLITIS ,medicine.disease ,Arthritis & Rheumatology ,Logistic Models ,Opioid ,Musculoskeletal ,Multivariate Analysis ,Self Report ,BASFI ,business ,Spondylitis ,Follow-Up Studies - Abstract
Objective.Opioid analgesics may be prescribed to ankylosing spondylitis (AS) patients with pain that is unresponsive to antirheumatic treatment. Our study assessed factors associated with opioid usage in AS.Methods.A prospective cohort of 706 patients with AS meeting modified New York criteria followed at least 2 years underwent comprehensive clinical evaluation of disease activity and functional impairment. These were assessed by the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and Bath Ankylosing Spondylitis Functional Index (BASFI). Radiographic severity was assessed by the Bath Ankylosing Spondylitis Radiology Index and modified Stokes Ankylosing Spondylitis Scoring System. Medications taken concurrently with opioids, as well as C-reactive protein (CRP) levels and erythrocyte sedimentation rate (ESR), were determined at each study visit, performed every 6 months. Analyses were carried out at baseline, and longitudinal multivariable models were developed to identify factors independently associated with chronic and intermittent opioid usage over time.Results.Factors significantly associated with opioid usage, especially chronic opioid use, included longer disease duration, smoking, lack of exercise, higher disease activity (BASDAI) and functional impairment (BASFI), depression, radiographic severity, and cardiovascular disease. Patients taking opioids were more likely to be using anxiolytic, hypnotic, antidepressant, and muscle relaxant medications. Multivariable analysis underscored the association with smoking, older age, antitumor necrosis factor agent use, and psychoactive drugs, as well as with subjective but not objective determinants of disease activity.Conclusion.Opioid usage was more likely to be associated with subjective measures (depression, BASDAI, BASFI) than objective measures (CRP, ESR), suggesting that pain in AS may derive from sources other than spinal inflammation alone.
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- 2017
8. SAT0400 Clinical Factors Impacting Statin Usage in A Longitudinal Ankylosing Spondylitis Cohort
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Jonathan D. Dau, Min Lee, M. Rahbar, Matthew A. Brown, Laura Diekman, Michael H. Weisman, M. M. Ward, Lianne S. Gensler, and John D. Reveille
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medicine.medical_specialty ,Ankylosing spondylitis ,Statin ,business.industry ,medicine.drug_class ,Immunology ,Confounding ,Small sample ,medicine.disease ,General Biochemistry, Genetics and Molecular Biology ,Rheumatology ,Internal medicine ,Cohort ,medicine ,Mixed effects ,Physical therapy ,Immunology and Allergy ,In patient ,business ,BASDAI - Abstract
Background Patients with ankylosing spondylitis (AS) are at higher risk for developing cardiovascular comorbidities. While aortic valve and conduction defects are most common, increased levels of LDL cholesterol are also seen. Statin usage has been reported to lower CRP and ESR though the power of these studies are limited due to small sample size and short-term follow-up (1,2). Objectives This study examines associations of statin usage with socio-demographic and clinical factors, including disease activity, functional impairment, and radiographic severity in patients with two years of follow-up or more. Methods 655 AS patients meeting modified New York criteria followed at least 2 years (and up to 12 years) were included in the analysis. Demographic and clinical parameters (disease activity and functional impairment were collected every 6 months, as well as radiographic assessments (BASRI and mSASSS) every 2 years. Univariable and multivariable mixed effect models were developed to identify independent factors associated with statin usage over time. Results Mean disease duration was 18 years (SD=13). 10% (n=66) of the cohort were using statins. Univariable longitudinal regression models are shown below: Multivariable longitudinal analyses controlling for confounders showed independent associations of age >40 years (p Conclusions Statin usage was, as expected, more likely in those of older age with greater disease duration and greater radiographic severity. Even though statins are known to reduce CRP, the association with markers of lower disease activity, both subjective (BASDAI on univariable analysis) and objective (CRP on both univariable and multivariable analyses), raises the possibility of a role in suppressing inflammation in patients with AS. References Heinemann S and Daemen M. Cardiovascular risks in spondyloarthropaties. Curt Opin Rheumatol. 2007 19:358–362. Denderen JC, Peters MJL, van Halm VP, van de Horst-Bruinsma, Dijkmans BAC, Nurmohamed MT. Statin therapy might be beneficial for patients with ankylosing spondylitis. Ann Rhem Dis. 2006; 65: 695–696. Disclosure of Interest J. Dau: None declared, M. Weisman Grant/research support from: UCB, Human Genome Sciences, Sanofi, Eli Lilly and Co, Genentech, Inc., Santarus Inc., EMD Serono, ChemoCentryx, GSK, Immunomedics Inc., Consultant for: Boehringer Ingelheim/Proskauer, Ardea Biosciences, Epirus Biopharmaceuticals, Acerta Pharma, M. Lee: None declared, M. Ward: None declared, M. Brown: None declared, L. Diekman: None declared, M. Rahbar: None declared, L. Gensler: None declared, J. Reveille: None declared
- Published
- 2016
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