Abstract
Objective
To investigate the performance and factors of influence of optical spectral transmission (OST) imaging as a new technique for measuring joint inflammation in rheumatoid arthritis (RA).
Method
OST was performed in 24 RA patients and 37 controls. Mann–Whitney U-test was used to assess differences in OST score between RA patients and controls. Receiver operating characteristics (ROC), linear regression and generalized estimating equations analysis were used to assess the discriminative capability of OST and the association of OST score with clinical disease parameters, ultrasound, radiographic features and cardiovascular risk parameters.
Results
Median OST score was higher in RA patients than in controls [16.9 (interquartile range 12.77–19.7) vs 12.11 (10.32–14.93)]. At patient level, OST score was moderately associated with ultrasound [beta 0.38 (95% CI 0.16–0.60), p = 0.001] and clinical disease activity [28-joint Disease Activity Score–C-reactive protein beta 0.30 (95% CI 0.04– 0.57), p = 0.024] in RA patients. In controls, male sex, high body mass index, and hypertension were associated with higher OST scores, while these associations were absent in RA. At joint level, the area under the ROC curve for OST score, with ultrasound or clinical swelling as reference, ranged from 0.63 to 0.70. Joint-space narrowing and malalignment were associated with higher OST joint scores, and subchondral sclerosis with lower scores.
Conclusion
OST provides an objective measure of synovitis and correlates moderately with other examined disease activity assessment tools. Clinical patient characteristics must be considered when interpreting the results.
Acknowledgements
We thank all nurses, physicians, technicians, and researchers who helped with data collection, in particular Maaike van Schaik, Ben Tuit, and Jerney de Jongh. We gratefully thank the Radiology Department of Reade for their support, with special thanks to Aja Kuin for performing part of the ultrasound investigations. We also thank MSD and Hemics for making the HandScan available and for their technical support. We would like to thank all patients of the outpatient clinics of Reade and Amsterdam UMC, location VUmc, who participated in this study.
Disclosure statement
Ronald F van Vollenhoven has received research and educational support (grants) from BMS, GSK, Lilly, Pfizer, Roche, and UCB, and compensation for consultancy and/or speaking from AbbVie, AstraZeneca, Biogen, Biotest, BMS, Galapagos, Gilead, GSK, Janssen, Pfizer, Sanofi, Servier, UCB, and Vielabio. Annelies B Blanken, Mies Korteweg, Laurette van Boheemen, Micheal T Nurmohamed, and Conny J van der Laken declare no potential conflicts of interest.
Trial registration
This study was registered in the Netherlands Trial Register on 30 August 2018, with trial number NTR7479.
Supplementary material
Supplemental data for this article can be accessed online at https://doi.org/10.1080/03009742.2023.2177382