Background:Rheumatoid arthritis (RA) is a long-term, progressive, and disabling autoimmune disease1. The disease activity can be quantified by the Disease Activity Score 28-joint count – C reactive protein (DAS28crp)2; the evaluation of disability function (DF) is actually mainly performed only by subjective Patient Reported Outcomes (PROs) like Health Assessment Questionnaire (HAQ)3; to investigate the functional aspects of RA hands it is usually used the grip strength (GS)4. However, in the scientific literature no tool, which objectively evaluates movement speed, has been reported. The Hand Test System (HTS, ETT) is an engineered glove (RAGLOVE), nowadays applied for neuroscience studies to evaluate hand motility5Objectives:To objectively evaluate the RA hand’s speed of the fine movements, through the HTS and to compared with a group of age and sex matched healthy controls. To verify the correspondence with the HAQ, DAS28, GS.Methods:55 consecutives RA patients (pts) (6 males, age 61 ± 16 years, mean duration of disease 12 ± 8 years), classified according to 2010 ACR/EULAR criteria6, and 50 matched healthy controls (HCs) were enrolled. After consent, all participants undergone HTS test that recognizes the touches between the finger tips during the opposition movements of the hands in standard sequences of movements, after dressed the glove. A multiple finger evaluation (MFE) and a single finger evaluation (SFE) were performed using a dedicated software that provided the physician the following quantitative parameters: Touch Duration (TD), Inter Tapping Interval (ITI) and Movement Rate (MR). Average time for hand 2 minutes. RA pts compiled the HAQ, performed the GS and a DAS28cpr was performed.The student’s t-test was used to compare the glove’s parameters between the groups whereas the analysis of variance (ANOVA) was utilized to verify potential differences between the populations. In order to evaluate the single correlations, the r and p values of Pearson were employed.Results:For MFE, glove parameters TD and ITI were significantly higher in RA pts than HCs, whereas; MR was significantly lower in RA pts compared to HCs (all p <0.001).For SFE non-affected fingers (not swollen and not tender) of RA pts performed better than a clinically affected fingers, but in any case significantly worse than average HCs fingers (p < 0.001).There is a statistically significant correlation between the GS and MR (r= 0.39 p=0.003) and TD (r=-0.33 p=0.015).TD, ITI e MR of RA pts showed a significant correlation with the total score of the HAQ (r = 0.56, r = 0.39, r = -0.56, all p < 0.001;). DAS28, considered as a continuous variable, proved to be significantly correlated with the TD (r = 0.36, p = 0.009). When the RA patients were grouped according to the disease activity by DAS28cpr7, there was an increase of one third of the TD’s logarithm for each increase in the activity class (linear regression with ordinal predictors, beta = 0.33; 95%CI 0.03, 0.63,p < 0.0297). Finally, even RA pts in remission showed a TD significantly higher compared with HCs (p= 0.034).Conclusion:The RAGLOVE is shown as a new safe and fast tool to evaluate a new objective parameter in the hand’s functionality: the speed of finger movements. In RA pts, an inversely proportional correlation emerges between the speed of movement and disease activity.The significant correlation found with HAQ, highlights the loss of motility of the hands as one of the main determinant of disability. The RAGLOVE is now tested in RA patients undergoing treatment.References:[1]Hakkinen et al Ann Rheum Dis. 2005;[2]Van Der Heijde et al J of Rheum. 1993;[3]Fries et al Arthritis Rheum. 1980;[4]Mathiowetz et al J Hand Surg Am. 1984;[5]Carmisciano et al Eur J Neurol. 2020;[6]Aletaha et al. Ann Rheum Dis. 2010;[7]Aletaha et al Arthritis Rheum 2005.Disclosure of Interests:None declared
Pre-analytical and analytical confounders of serum calprotectin as a biomarker in rheumatoid arthritis
