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1.
Ann Rheum Dis ; 83(5): 599-607, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38228361

RESUMEN

OBJECTIVES: The study aimed to evaluate the effect of adding a non-steroidal anti-inflammatory drug (NSAID), celecoxib (CEL), to a tumour necrosis factor inhibitor (TNFi), golimumab (GOL), compared with TNFi monotherapy on radiographic spinal progression in patients with radiographic axial spondyloarthritis (r-axSpA) over 2 years. METHODS: R-axSpA patients, having risk factors for radiographic progression (high disease activity plus C reactive protein >5 mg/L and/or ≥1 syndesmophyte(s)), underwent a 12-week run-in phase with GOL 50 mg every 4 weeks. In the core phase (96 weeks), only patients with a good clinical response at week 12 were randomised (1:1) to GOL+CEL 200 mg two times per day (combination therapy) or GOL monotherapy. The primary endpoint was radiographic progression assessed by modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) change at week 108 in the intent-to-treat population. RESULTS: A total of 128 patients were enrolled in the run-in phase; and 109 patients were randomised at week 12 to monotherapy (n=55) or combination therapy (n=54). At week 108, 97 (52 vs 45) patients completed the study. The change in mSASSS at week 108 was 1.7 (95% CI 0.8 to 2.6) in the monotherapy vs 1.1 (95% CI 0.4 to 1.8) in the combination therapy groups (p=0.79). New syndesmophytes occurred in 25% of patients in the monotherapy vs 11% of patients in the combination therapy groups (p=0.12). During the study, no significant differences in adverse events and serious adverse events were observed between the groups. CONCLUSIONS: Combination therapy with GOL+CEL did not demonstrate statistically significant superiority over GOL monotherapy in retarding radiographic spinal progression over 2 years in r-axSpA.


Asunto(s)
Espondiloartropatías , Espondilitis Anquilosante , Humanos , Antiinflamatorios no Esteroideos/uso terapéutico , Inhibidores del Factor de Necrosis Tumoral/uso terapéutico , Radiografía , Columna Vertebral/diagnóstico por imagen , Columna Vertebral/patología , Espondilitis Anquilosante/tratamiento farmacológico , Celecoxib/uso terapéutico , Espondiloartropatías/tratamiento farmacológico , Progresión de la Enfermedad
2.
RMD Open ; 8(2)2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36323487

RESUMEN

OBJECTIVES: This study aimed to evaluate the Disease Activity index for PSoriatic Arthritis (DAPSA) based on a quick quantitative C reactive protein (qCRP) assay (Q-DAPSA) in a multicentre, prospective, cross-sectional study in patients with psoriatic arthritis (PsA). METHODS: The assessment of prospectively recruited study patients included joint examination and patient reported outcome (PRO) measures (patient global assessment, patient pain assessment). Following, the DAPSA based on a routine laboratory CRP measurement, Q-DAPSA and clinical DAPSA (cDAPSA) were calculated. Cross-tabulations and weighted Cohen's kappa were performed to analyse the agreement of disease activity categories. Bland-Altman plots and intraclass correlation coefficients were used to determine the agreement of numerical values regarding CRP and qCRP as well as different disease activity scores. RESULTS: Altogether, 104 patients with PsA could be included in the statistical analysis. With Q-DAPSA, 102 of 104 (98.1%) patients achieved identical disease activity categories in comparison to DAPSA with a weighted Cohen's kappa of 0.980 (95% CI: 0.952 to 1.000). The agreement between DAPSA and cDAPSA was slightly lower with identical disease activity categories seen in 97 of 104 (93.3%) of patients and with a weighted Cohen's kappa of 0.932 (95% CI 0.885 to 0.980). CONCLUSIONS: The Q-DAPSA showed an almost perfect agreement with the conventional DAPSA regarding identical disease activity categories. Thus, the Q-DAPSA can be used as a timely available disease activity score in patients with PsA with the additional benefit of CRP involvement. Consequently, the Q-DAPSA could facilitate the implementation of the treat-to-target concept in clinical routine and clinical trials.


Asunto(s)
Artritis Psoriásica , Humanos , Artritis Psoriásica/diagnóstico , Artritis Psoriásica/tratamiento farmacológico , Estudios Transversales , Proteína C-Reactiva/metabolismo , Estudios Prospectivos , Inducción de Remisión , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
3.
Ther Adv Musculoskelet Dis ; 14: 1759720X221114107, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36003590

RESUMEN

Objectives: The Simplified Disease Activity Index (SDAI) is a recommended composite score for assessing the remission status in patients with rheumatoid arthritis (RA). However, determination of C-reactive protein (CRP) levels takes several hours and sometimes days and limits the use of the SDAI in the clinical setting. The aim of this study was to validate the SDAI using a quick quantitative C-reactive protein (qCRP) assay (as SDAI-Q) in RA patients. Design: This is a multicenter, prospective, cross-sectional pilot study in RA patients. Methods: Adult patients (⩾18 years) with a clinical diagnosis of RA were recruited between January 2020 and September 2020 from five rheumatologic centers located in Berlin, Germany. SDAI, SDAI-Q, Clinical Disease Activity Index (CDAI), and DAS28 scores comprising CRP, qCRP, or erythrocyte sedimentation rate (ESR) were calculated. The agreement of disease activity categories was analyzed using cross tabulations and weighted Cohen's kappa. The agreement of numerical values was analyzed with Bland-Altman plots and intraclass correlation coefficients (ICCs). Results: Overall, 100 RA patients were included in the statistical analysis. The mean value of qCRP (7.89 ± 16.98 mg/l) was slightly higher than that of routine laboratory CRP (6.97 ± 15.02 mg/l). Comparing SDAI and SDAI-Q, all patients were assigned to identical disease activity categories. Agreement of disease activity categories by CDAI and SDAI/SDAI-Q was observed in 93% with a weighted Cohen's kappa of 0.929 (95% confidence interval (CI) = 0.878; 0.981). Conclusion: The SDAI-Q showed an absolute agreement regarding the assignment of disease activity categories in comparison with the conventional SDAI. Therefore, the SDAI-Q may facilitate the application of a treat-to-target concept in clinical trials and clinical routine as a quickly available disease activity score incorporating CRP as an objective parameter.

4.
Ann Rheum Dis ; 2022 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-35697486

RESUMEN

OBJECTIVE: The objective of the current study was to analyse the association between treatment with tumour necrosis factor inhibitors (TNFi) and radiographic spinal progression in patients with axial spondyloarthritis (axSpA) from a long-term inception cohort. METHODS: A total of 243 patients with axSpA from the German Spondyloarthritis Inception Cohort with at least two sets of spinal radiographs obtained at least 2 years apart during a 10-year follow-up were included. Spinal radiographs were evaluated by three trained and calibrated readers according to the modified Stoke Ankylosing Spondylitis Spine Score (mSASSS). The association between the current TNFi, previous TNFi and radiographic spinal progression defined as the absolute mSASSS change score over 2 years was analysed using longitudinal generalised estimating equations analysis. RESULTS: TNFi treatment in the current 2-year interval was not associated with retardation of radiographic spinal progression (ß=-0.02 (95% CI -0.37 to 0.34) and -0.17 (95% CI -0.54 to 0.20) for any and ≥12 months treatment duration, respectively, adjusted for sex, the Ankylosing Spondylitis Disease Activity Score, smoking, presence of definite radiographic sacroiliitis, mSASSS at baseline and non-steroidal anti-inflammatory drug intake). TNFi treatment in the previous 2-year interval, was, however, significantly associated with reduction of mSASSS progression, which was especially evident in patients who received TNFi in the previous and in the current intervals: ß=-0.58 (95% CI -1.02 to -0.13), adjusted for the same variables. CONCLUSION: TNFi treatment was associated with a time-shifted effect on radiographic spinal progression in axSpA that became evident between years 2 and 4 after treatment initiation.

5.
Arthritis Rheumatol ; 74(9): 1515-1523, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35437900

RESUMEN

OBJECTIVE: To investigate the longitudinal association between radiographic sacroiliitis progression and treatment with tumor necrosis factor inhibitors (TNFi) in patients with early axial spondyloarthritis (SpA) in a long-term inception cohort. METHODS: We included patients from the German Spondyloarthritis Inception Cohort who underwent radiographic assessment of the sacroiliac joints at baseline and at least once more during the 10-year follow-up. Two central readers scored the radiographs according to the modified New York criteria for ankylosing spondylitis. The sacroiliac sum score was calculated as a mean of the scores determined by both readers. TNFi use was assessed according to exposure in the current and/or previous 2-year radiographic interval. The association between TNFi use and radiographic sacroiliitis progression was examined by longitudinal generalized estimating equation analysis with adjustment for potential confounders. RESULTS: In this long-term inception cohort, 10-year follow-up data on 737 radiographic intervals assessed in 301 patients with axial SpA (166 patients with nonradiographic axial SpA and 135 patients with radiographic axial SpA) were obtained. Having received ≥12 months of treatment with TNFi in the previous 2-year radiographic interval was associated with a significant decrease in the sacroiliitis sum score (ß = -0.09 [95% confidence interval (95% CI) -0.18, -0.003]; analyses adjusted for age, sex, symptom duration, HLA-B27 status, Bath Ankylosing Spondylitis Disease Activity Index score, C-reactive protein, and nonsteroidal antiinflammatory drug intake). In contrast, among patients receiving TNFi in the current radiographic interval, there was no significant association with change in the sacroiliitis sum score (ß = 0.05 [95% CI -0.05, 0.14]). This effect of having received ≥12 months of treatment with TNFi in the previous 2-year radiographic interval was stronger in patients with nonradiographic axial SpA as compared to patients with radiographic axial SpA (ß = -0.16 [95% CI -0.28, -0.03] versus ß = -0.04 [95% CI -0.15, 0.07]). CONCLUSION: Treatment with TNFi was associated with the reduction in radiographic sacroiliitis progression in patients with axial SpA. This effect became evident between 2 and 4 years after treatment was initiated.


Asunto(s)
Espondiloartritis Axial , Sacroileítis , Espondiloartritis , Espondilitis Anquilosante , Humanos , Sacroileítis/complicaciones , Sacroileítis/diagnóstico por imagen , Sacroileítis/tratamiento farmacológico , Espondiloartritis/complicaciones , Espondiloartritis/diagnóstico por imagen , Espondiloartritis/tratamiento farmacológico , Espondilitis Anquilosante/tratamiento farmacológico , Inhibidores del Factor de Necrosis Tumoral
6.
Ther Adv Musculoskelet Dis ; 14: 1759720X221085951, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35368376

RESUMEN

Objectives: The objective of the study was to validate the Ankylosing Spondylitis Disease Activity Score (ASDAS) based on a quick quantitative C-reactive protein (qCRP) assay (ASDAS-Q) in a multicentre, prospective, cross-sectional study in patients with axial spondyloarthritis (axial SpA). Methods: Disease activity assessment was performed in prospectively recruited patients with axial SpA. Routine laboratory CRP was determined in the central laboratory of each study centre, while quick qCRP and erythrocyte sedimentation rate (ESR) were measured locally. Consequently, ASDAS-CRP, ASDAS-Q using the qCRP and ASDAS-ESR were calculated. The absolute agreement on the disease activity category ascertainment was analysed with cross-tabulations and weighted Cohen's kappa. Bland-Altman plots and intraclass correlation coefficients (ICCs) were used to analyse the criterion validity. Results: Overall, 251 axial SpA patients were included in the analysis. The mean qCRP value (6.34 ± 11.13 mg/l) was higher than that of routine laboratory CRP (5.26 ± 9.35 mg/l). The ICC for routine laboratory CRP versus qCRP was 0.985 [95% confidence interval (CI): 0.972-0.991]. Comparing ASDAS-Q with ASDAS-CRP, 242 of 251 (96.4%) patients were assigned to the same disease activity categories with a weighted Cohen's kappa of 0.966 (95% CI: 0.943-0.988) and ICC of 0.997 (95% CI: 0.994-0.999). Conclusions: ASDAS-Q showed an almost perfect agreement with ASDAS-CRP in the assignment to specific disease activity categories. Consequently, ASDAS-Q using the qCRP value can be applied as an accurate and quickly available alternative to ASDAS-CRP, thus facilitating the implementation of the treat-to-target concept in clinical trials and clinical routine.

7.
Joint Bone Spine ; 89(5): 105367, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35227921

RESUMEN

OBJECTIVE: To determine the SpA prevalence and identify its associated factors in Crohn's disease (CD) patients receiving a systematically rheumatological and imaging assessment, including magnetic resonance imaging (MRI) of the sacroiliac joints and spine. METHODS: CD patients either naive to biologics or without them for three months prior enrollment were recruited in a subgroup of the German Spondyloarthritis Inception Cohort (GESPIC-Crohn). A structured assessment of SpA manifestations was performed by a rheumatologist, including MRI of sacroiliac joints and spine. Demographic and clinical parameters including disease activity in CD (Harvey Bradshaw Index-HBI) and SpA (C-reactive protein - CRP, Bath Ankylosing Spondylitis Disease Activity Index, and Ankylosing Spondylitis Disease Activity Score) were collected. Univariable and multivariable logistic regression analyses were performed to identify factors associated with the presence of SpA. RESULTS: A total of 103 patients with CD were included in the cohort. The mean CD disease duration was 1.3±2.4years and 95.1% were naïve to biologics. The most frequent musculoskeletal manifestation was back pain (65.0%), followed by chronic back pain (50.5%), and arthralgia (43.7%). Prevalence of SpA was 19.4% with slightly higher proportion of axial SpA than peripheral SpA, and higher proportion of radiographic axial SpA (7.4%) than non-radiographic axial SpA (2.8%). Changes in MRI compatible with axial SpA were found in 15 (14.7%) patients, of which 9 (81.1%) patients had the clinical diagnosis of axial SpA. HLA-B27 positivity (OR 9.02, CI 95% 2.29-35.55) and higher disease activity of CD as reflected by the HBI (OR 1.14, 95%CI 1.01-1.30) were significant and independently associated with the presence of SpA. CONCLUSION: SpA was present in nearly one out of five patients with CD and it was associated with the expression of HLA-B27 and a higher clinical activity of CD. Our findings raise awareness to rheumatologists and gastroenterologists on the high concomitance between both diseases and may help to reduce the delay in SpA diagnosis.


Asunto(s)
Productos Biológicos , Enfermedad de Crohn , Espondiloartritis , Espondilitis Anquilosante , Dolor de Espalda/diagnóstico , Proteína C-Reactiva , Enfermedad de Crohn/complicaciones , Enfermedad de Crohn/diagnóstico por imagen , Enfermedad de Crohn/epidemiología , Antígeno HLA-B27 , Humanos , Imagen por Resonancia Magnética/métodos , Estudios Prospectivos , Articulación Sacroiliaca/diagnóstico por imagen , Articulación Sacroiliaca/patología , Espondiloartritis/complicaciones , Espondiloartritis/diagnóstico por imagen , Espondiloartritis/epidemiología , Espondilitis Anquilosante/complicaciones , Espondilitis Anquilosante/diagnóstico por imagen , Espondilitis Anquilosante/epidemiología
8.
Semin Arthritis Rheum ; 53: 151974, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35150984

RESUMEN

OBJECTIVE: To analyze whether biomarker levels at baseline or their change after 3 months or 2 years predict radiographic spinal progression in ankylosing spondylitis (AS) patients treated with TNF-α inhibitors (TNFi). METHODS: 137 AS patients from the Groningen Leeuwarden Axial Spondyloarthritis (GLAS) cohort were included before starting TNFi. Serum biomarkers were measured at baseline, 3 months and 2 years: Markers of inflammation (calprotectin, matrix metalloproteinase-3, vascular endothelial growth factor), bone turnover markers (bone-specific alkaline phosphatase, serum C-terminal telopeptide fragments of type I collagen (sCTX), osteocalcin, osteoprotegerin, procollagen type I and II N-terminal propeptide, sclerostin) and adipokines (high-molecular-weight adiponectin, leptin, visfatin). Spinal radiographs were scored at baseline, 2 and 4 years. Logistic regression was performed to examine the association between biomarker values and radiographic spinal progression, adjusting for known risk factors for radiographic progression. RESULTS: Baseline calprotectin and visfatin levels were associated with mSASSS progression ≥2 points (OR 1.195 [95%CI 1.055-1.355] and 1.465 [1.137-1.889], respectively), while calprotectin was also associated with new syndesmophyte formation after 2 years (OR 1.107 [1.001-1.225]). Baseline leptin level was associated with mSASSS progression ≥4 points after 4 years (OR 0.614 [0.453-0.832]), and baseline sCTX level with syndesmophyte formation after 4 years (OR 1.004 [1.001-1.008]). Furthermore, change of visfatin and leptin levels over the first 2 years showed significant association with radiographic progression after 4 years. CONCLUSION: Independent of known risk factors, serum levels of biomarkers at baseline are able to predict radiographic spinal progression over 2 and 4 years in AS patients on TNFi therapy.


Asunto(s)
Adipoquinas , Remodelación Ósea , Espondilitis Anquilosante , Adipoquinas/sangre , Biomarcadores/sangre , Progresión de la Enfermedad , Humanos , Inflamación/sangre , Espondilitis Anquilosante/diagnóstico por imagen , Espondilitis Anquilosante/tratamiento farmacológico , Inhibidores del Factor de Necrosis Tumoral/uso terapéutico
9.
BMJ Open ; 11(11): e048647, 2021 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-34785545

RESUMEN

INTRODUCTION: Psoriatic arthritis (PsA) is an inflammatory disease characterised by synovitis, enthesitis, dactylitis and axial involvement. The prevalence of axial involvement ranges from 25% to 70% in this patient group. Treatment recommendations for axial PsA were mainly extrapolated from guidelines for axial spondyloarthritis, and the main treatment options are non-steroidal anti-inflammatory drugs and biological disease-modifying antirheumatic drugs (tumour necrosis factor, IL-17 and IL-23 inhibitors). Tofacitinib was approved for the treatment of PsA and its efficacy on axial inflammation has been demonstrated in a phase II study of ankylosing spondylitis (AS). This prospective study aims to evaluate the efficacy of tofacitinib in reducing inflammation in the sacroiliac joints (SIJs) and spine on MRI in patients with axial disease of their PsA presenting with active axial involvement compatible with axial PsA. METHODS AND ANALYSES: This is a randomised, double-blind, placebo-controlled, multicentre clinical trial in patients with axial PsA who have evidence of axial involvement, active disease as defined by a Bath AS Disease Activity Index score of ≥4 and active inflammation on MRI of the SIJs and/or spine as assessed by and independent central reader. The study includes a 6-week screening period, a 24-week treatment period, which consist of a 12-week placebo-controlled double-blind treatment period followed by a 12-week active treatment period with tofacitinib for all participants, and a safety follow-up period of 4 weeks. At baseline, 80 subjects shall be randomised (1:1) to receive either tofacitinib or matching placebo for a 12-week double-blind treatment period. At week 12, an MRI of the whole spine and SIJs will be performed to evaluate the primary study endpoint. ETHICS AND DISSEMINATION: The study will be performed according to the ethical principles of the Declaration of Helsinki and the German drug law. The independent ethics committees of each centre approved the ethical, scientific and medical appropriateness of the study before it was conducted. TRIAL REGISTRATION NUMBER: NCT04062695; ClinicalTrials.gov and EudraCT No: 2018-004254-22; European Union Clinical Trials Register.


Asunto(s)
Antirreumáticos , Artritis Psoriásica , Espondiloartritis Axial , Antirreumáticos/uso terapéutico , Artritis Psoriásica/diagnóstico por imagen , Artritis Psoriásica/tratamiento farmacológico , Método Doble Ciego , Humanos , Inflamación/tratamiento farmacológico , Imagen por Resonancia Magnética , Estudios Multicéntricos como Asunto , Piperidinas , Estudios Prospectivos , Pirimidinas , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
10.
RMD Open ; 7(2)2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34187873

RESUMEN

OBJECTIVE: Genetic determinants of fibrin clot formation and fibrinolysis have an impact on local and systemic inflammatory response. The aim of the present study was to assess whether coagulation-related genotypes affect the predictive value of C-reactive protein (CRP) in regards of radiographic spinal progression in axial spondyloarthritis (axSpA). METHODS: Two hundred and eight patients with axSpA from the German Spondyloarthritis Inception Cohort were characterised for genotypes of α-fibrinogen, ß-fibrinogen (FGB) and γ-fibrinogen, factor XIII A-subunit (F13A) and α2-antiplasmin (A2AP). The relation between CRP levels and radiographic spinal progression defined as worsening of the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) by ≥2 points over 2 years was assessed in dependence on the respective genetic background in logistic regression analyses. RESULTS: Overall, CRP was associated with mSASSS progression ≥2 points: time-averaged CRP ≥10 mg/L, OR: 3.32, 95% CI 1.35 to 8.13. After stratification for coagulation-related genotypes, CRP was strongly associated with mSASSS progression in individuals predisposed to form loose, fibrinolysis-susceptible fibrin clots (FGB rs1800790GG, OR: 6.86, 95% CI 2.08 to 22.6; A2AP 6Trp, OR: 5.86, 95% CI 1.63 to 21.0; F13A 34Leu, OR: 8.72, 95% CI 1.69 to 45.1), while in genotypes predisposing to stable fibrin clots, the association was absent or weak (FGB rs1800790A, OR: 0.83, 95% CI 0.14 to 4.84; A2AP 6Arg/Arg, OR: 1.47, 95% CI 0.35 to 6.19; F13A 34Val/Val, OR: 1.72, 95% CI 0.52 to 5.71). CONCLUSIONS: Elevated CRP levels seem to be clearly associated with radiographic spinal progression only if patients are predisposed for loose fibrin clots with high susceptibility to fibrinolysis.


Asunto(s)
Proteína C-Reactiva , Espondiloartritis , Proteína C-Reactiva/genética , Fibrina , Fibrinólisis/genética , Humanos , Columna Vertebral
11.
Int J Mol Sci ; 21(24)2020 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-33317138

RESUMEN

OBJECTIVE: Coagulation and fibrinolysis are interrelated with the expression of vascular endothelial growth factor (VEGF), which frequently is increased in axial spondyloarthritis (axSpA). We tested whether (i) α2-antiplasmin (A2AP) Arg6Trp, (ii) fibrinogen, factor XIII A-subunit or B-subunit genotypes are associated with VEGF levels and assessed whether the known association between elevated VEGF and radiographic spinal progression in axSpA depends on genetic background. METHODS: One hundred and eighty-six axSpA patients from the German Spondyloarthritis Inception Cohort were genotyped, characterized for VEGF levels, and statistically analyzed. The association between VEGF and radiographic spinal progression was assessed in dependence on genetic background in stratified analyses. RESULTS: A2AP 6Trp carriage was associated with VEGF elevation (OR: 2.37, 95% CI: 1.06-5.29) and VEGF levels (6Trp, 455 ± 334 pg/mL; 6Arg/Arg, 373 ± 293 pg/mL; p < 0.008). Association between elevated VEGF and radiographic spinal progression in axSpA (OR: 3.11, 95% CI: 1.02-8.82) depended remarkably on the fibrinogen (FGA) genotype. When considering axSpA patients with elevated VEGF, in FGA rs6050A>G wild types, 42.1% of patients (8 of 19) progressed, while in G-allele carriers, no radiographic progression happened (0 of 13) (p < 0.04). CONCLUSIONS: The A2AP Arg6Trp genotype seems to influence VEGF levels in axSpA. The predictive value of VEGF elevations in respect of radiographic spinal progression in axSpA depends on FGA genotypes.


Asunto(s)
Fibrinógeno/genética , Genotipo , Espondilitis Anquilosante/genética , Factor A de Crecimiento Endotelial Vascular/genética , alfa 2-Antiplasmina/genética , Adulto , Factor VIII/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Espondilitis Anquilosante/diagnóstico por imagen , Espondilitis Anquilosante/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo
12.
J Clin Epidemiol ; 68(1): 61-72, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25441701

RESUMEN

OBJECTIVES: Bivariate linear and generalized linear random effects are frequently used to perform a diagnostic meta-analysis. The objective of this article was to apply a finite mixture model of bivariate normal distributions that can be used for the construction of componentwise summary receiver operating characteristic (sROC) curves. STUDY DESIGN AND SETTING: Bivariate linear random effects and a bivariate finite mixture model are used. The latter model is developed as an extension of a univariate finite mixture model. Two examples, computed tomography (CT) angiography for ruling out coronary artery disease and procalcitonin as a diagnostic marker for sepsis, are used to estimate mean sensitivity and mean specificity and to construct sROC curves. RESULTS: The suggested approach of a bivariate finite mixture model identifies two latent classes of diagnostic accuracy for the CT angiography example. Both classes show high sensitivity but mainly two different levels of specificity. For the procalcitonin example, this approach identifies three latent classes of diagnostic accuracy. Here, sensitivities and specificities are quite different as such that sensitivity increases with decreasing specificity. Additionally, the model is used to construct componentwise sROC curves and to classify individual studies. CONCLUSION: The proposed method offers an alternative approach to model between-study heterogeneity in a diagnostic meta-analysis. Furthermore, it is possible to construct sROC curves even if a positive correlation between sensitivity and specificity is present.


Asunto(s)
Análisis por Conglomerados , Diagnóstico , Metaanálisis como Asunto , Modelos Estadísticos , Curva ROC , Enfermedad de la Arteria Coronaria/diagnóstico , Humanos , Proyectos de Investigación , Sensibilidad y Especificidad
13.
Biomed Tech (Berl) ; 59(1): 29-37, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24334421

RESUMEN

OBJECTIVES: A non-contrast-enhanced 2D time-of-flight magnetic resonance angiography (TOF-MRA) protocol was compared with the gold standard of planar digital subtraction angiography (DSA) by calculating correlations of vessel diameters. METHODS: A total of 1134 vascular diameters in 81 corresponding sites were prospectively measured by TOF-MRA and DSA in seven patients (four women, three men; mean age, 68 years). For a total of 162 vascular segments per patient, 81 Spearman's ρ correlation coefficients were calculated, consolidated to 41 due to consideration of symmetry (right/left), and assessed by correlation quality. RESULTS: In the 41 consolidated segments, correlations were good, very good, and excellent in 25 segments (n=10>0.5, n=4>0.7, and n=11>0.8), moderate to poor in seven segments (n=4>0.3 and 0

Asunto(s)
Angiografía de Substracción Digital/métodos , Técnicas de Imagen Sincronizada Cardíacas/métodos , Interpretación de Imagen Asistida por Computador/métodos , Pierna/irrigación sanguínea , Angiografía por Resonancia Magnética/métodos , Pelvis/irrigación sanguínea , Enfermedad Arterial Periférica/diagnóstico , Anciano , Femenino , Humanos , Pierna/diagnóstico por imagen , Pierna/patología , Masculino , Persona de Mediana Edad , Pelvis/diagnóstico por imagen , Pelvis/patología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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