The first section of this thesis aims to provide an international perspective on the characterisation of patients with axial spondyloarthritis. Through different aspects of the classification... Show moreThe first section of this thesis aims to provide an international perspective on the characterisation of patients with axial spondyloarthritis. Through different aspects of the classification criteria, we review the importance of global applicability of these criteria. As classification criteria ensure the same patients are selected for participation in clinical trials worldwide, global applicability would allow for direct comparisons between studies executed in different geographical regions. Likewise, standardised assessment and reporting of results from clinical trials allows for direct comparisons between studies investigating different treatments, or identical treatments in populations from a different ethnicity or background, which is debated in the second part of this thesis. Herein, we describe the process of the development of the core set for axial spondyloarthritis, specifically by updating the domains of the ASAS-OMERACT core set for ankylosing spondylitis. In the final part of this thesis, we discuss health-related quality of life and work and activity impairments in patients with chronic back pain suspected of axial spondyloarthritis. Show less
Maarseveen, T.D.; Maurits, M.P.; Niemantsverdriet, E.; Helm-van Mil, A.H.M. van der; Huizinga, T.W.J.; Knevel, R. 2021
Background Electronic health records (EHRs) offer a wealth of observational data. Machine-learning (ML) methods are efficient at data extraction, capable of processing the information-rich free... Show moreBackground Electronic health records (EHRs) offer a wealth of observational data. Machine-learning (ML) methods are efficient at data extraction, capable of processing the information-rich free-text physician notes in EHRs. The clinical diagnosis contained therein represents physician expert opinion and is more consistently recorded than classification criteria components. Objectives To investigate the overlap and differences between rheumatoid arthritis patients as identified either from EHR free-text through the extraction of the rheumatologist diagnosis using machine-learning (ML) or through manual chart-review applying the 1987 and 2010 RA classification criteria. Methods Since EHR initiation, 17,662 patients have visited the Leiden rheumatology outpatient clinic. For ML, we used a support vector machine (SVM) model to identify those who were diagnosed with RA by their rheumatologist. We trained and validated the model on a random selection of 2000 patients, balancing PPV and sensitivity to define a cutoff, and assessed performance on a separate 1000 patients. We then deployed the model on our entire patient selection (including the 3000). Of those, 1127 patients had both a 1987 and 2010 EULAR/ACR criteria status at 1 year after inclusion into the local prospective arthritis cohort. In these 1127 patients, we compared the patient characteristics of RA cases identified with ML and those fulfilling the classification criteria. Results The ML model performed very well in the independent test set (sensitivity=0.85, specificity=0.99, PPV=0.86, NPV=0.99). In our selection of patients with both EHR and classification information, 373 were recognized as RA by ML and 357 and 426 fulfilled the 1987 or 2010 criteria, respectively. Eighty percent of the ML-identified cases fulfilled at least one of the criteria sets. Both demographic and clinical parameters did not differ between the ML extracted cases and those identified with EULAR/ACR classification criteria. Conclusions With ML methods, we enable fast patient extraction from the huge EHR resource. Our ML algorithm accurately identifies patients diagnosed with RA by their rheumatologist. This resulting group of RA patients had a strong overlap with patients identified using the 1987 or 2010 classification criteria and the baseline (disease) characteristics were comparable. ML-assisted case labeling enables high-throughput creation of inclusive patient selections for research purposes. Show less
In this thesis we have pursued innovative analytical solutions for some of the most challenging questions in the field of SpA. We have gained better insights into the concept of axSpA by studying... Show moreIn this thesis we have pursued innovative analytical solutions for some of the most challenging questions in the field of SpA. We have gained better insights into the concept of axSpA by studying it independently of the rheumatologist’s opinion. Our findings likely add knowledge to what axSpA really is. Future studies will learn us how much of these insights will translate into a better recognition of the disease in clinical practice and in better classifying them for research purposes. Since SpA is a slowly progressing disease, several years are needed to see meaningful changes in imaging abnormalities of the axial skeleton, which poses methodological challenges. We have shown that thoughtful analytical approaches, that make best use of imaging data, are helpful in better estimating progression, in unravelling its determinants and in clarify which outcomes are best to monitor disease. Efforts are made to further improve outcome measurement in axSpA, including the development of new imaging techniques, which can benefit from our proposed solutions to long-term imaging scoring. Show less
In this thesis the focus was on diagnosing axSpA early using clinical features as well as imaging modalities. We have studied multiple elements diagnosing axSpA among patients presenting with... Show moreIn this thesis the focus was on diagnosing axSpA early using clinical features as well as imaging modalities. We have studied multiple elements diagnosing axSpA among patients presenting with chronic back pain. We have emphasized two main themes: (1) the importance of clinical SpA features; and (2) the contribution of imaging to an axSpA diagnosis and classification. We have learned how rheumatologists use imaging results in their diagnostic considerations and thereby have helped reduce certain fears regarding the way diagnosis is made in clinical practice. We have shown that the use of MRI-spine in classification is not efficient. The common thread in all of the studies in this thesis is that axSpA diagnosis is the interaction between the clinical aspects of chronic back pain and imaging findings highly suggestive of axSpA. Clinicians should be aware of mindlessly ‘stacking up’ SpA features in chronic back pain patients in order to avoid unnecessary (biologic) treatment. Additional studies are needed to investigate the numerous phenotypes of axSpA and to predict in which chronic back pain patient axSpA diagnosis is likely. Show less
Spondyloarthritis comprises a heterogeneous group of distinct disorders including ankylosing spondylitis, non-radiographic axial spondyloarthritis, psoriatic arthritis, arthritis related to... Show moreSpondyloarthritis comprises a heterogeneous group of distinct disorders including ankylosing spondylitis, non-radiographic axial spondyloarthritis, psoriatic arthritis, arthritis related to inflammatory bowel disease and reactive arthritis. Spondyloarthritis is the second most prevalent form of chronic inflammatory arthritis, with an estimated prevalence of about 0.5-1.5%. The studies presented in this thesis cover many aspects related to Spondyloarthritis in Colombia. The following topics were addressed. First, the analyses and performance of the different classification criteria and the factors important in the decision of the rheumatologist to order an MRI or HLA-B27 test in the diagnostic work-up of spondyloarthritis in the context of the clinical rheumatology setting. Second, a better insight was obtained with regard to the presence of comorbidities and risk factors of patients with spondyloarthritis. This included also a case control study to evaluate the relationship between periodontitis and spondyloarthritis. Third, the translation and cross-cultural adaptation to Spanish of the ASAS-HI was performed. Adittionally, the implementation of the domains and instruments of the ASAS core set in clinical trials have been evaluated. Finally, we discuss the potential unmet needs in the field of rheumatology in Colombia and we propose a research agenda for the upcoming years. Show less
Boeters, D.M.; Gaujoux-Viala, C.; Constantin, A.; Helm-van Mil, A.H.M. van der 2017
Spondyloarthritis (SpA) is a heterogeneous group of rheumatic diseases, characterized by sacroiliac-joint inflammation (sacroiliitis), peripheral and extra-articular complaints. The lack of... Show moreSpondyloarthritis (SpA) is a heterogeneous group of rheumatic diseases, characterized by sacroiliac-joint inflammation (sacroiliitis), peripheral and extra-articular complaints. The lack of diagnostic criteria makes diagnosing SpA challenging, yet, classification criteria are available. We tested the performance (sensitivity, specificity) of various classification criteria; the recently developed Assessment of SpondyloArthritis international Society (ASAS) criteria outperformed all other criteria. We investigated the discrepancies in interpretation MRIs and conventional radiographs on the presence of sacroiliitis; agreement on radiographic sacroiliitis between different readers is only moderate, but agreement regarding sacroiliitis on MRI is substantial. Rheumatologists take into account all clinical and laboratory results in addition to the imaging results in the diagnostic process. The diagnostic Berlin algorithm - in which all relevant results are taken into account __ can assist rheumatologists. We proposed a modification of this algorithm, which is accepted by ASAS and also included in the recently published guidelines for the diagnosis and treatment of SpA by the Dutch Society for Rheumatology. Besides, we performed systematic literature reviews, forming the base for the update of the ASAS management recommendations. With these results, SpA-patients can be recognized earlier, offering better treatment options and better outcomes. However, further improvements of care for SpA-patients are necessary. Show less
