LAUSR

Background Pain remains the most important challenge for rheumatoid arthritis (RA) patients. In order to cope with pain in RA, clinicians firstly need to understand the degree of patients’pain. When self reported measures such as visual analog scale were used, inconsistency between clinicians’ and patients’ ratings of pain was demonstrated (1). As a result, inability to fully assess the pain will cause the inability to fully assess the impact of pain on disease severity. Measuring pressure pain threshold with pressure algometry may provide additional advantages for the evaluation of pain and disease severity when compared with self-reported measures. Objectives The aim of this study was to evaluate the pain threshold and to determine the variables associated with pain threshold in the patients with RA. Methods The current study included 100 RA patients and 80 age-sex matched controls with non-inflammatory chronic low back pain. Clinical parameters, functional status, disease activity, pain, fatigue, depression, anxiety, pain catastrophizing and laboratory activity of RA patients were recorded. The pressure pain thresholds on the dominant thumb nail bed, trapezius and wrist of the two groups were measured by the algometer. The pain thresholds of the paients with RA and controls were compared. Moreover, the relation between pain threholds and all evaluated parameters in RA patients was analysed. Results The mean age of RA patients was 55.93 ± 10.81; the mean age of the controls was 54,50 ± 9,47. The pain thresholds of RA patients and controls were statistically similar in all areas. When the parameters found to be significantly correlated with pain threshold in RA patients were analyzed by regression analysis, depression was the only factor associated with low pain threshold in all areas (Table 1). Conclusion We found that depression was the only factor associated with low pain threshold in the patients with RA. The use of pressure algometry in the evaluation of chronic pain could offer an additional method to detect pain/depression overlap.Table 1 The correlation between pain threshold values and demographic, clinical and laboratory parameters of RA patients Nail PT Wrist PT Trapezius PT p r p r p r Age 0,551 0,060 0,705 0,038 0,806 0,025 BMI (kg/m2) 0,174 -0,137 0,066 -0,185 0,046* -0,200 Duration of disease (year) 0,247 -0,117 0,144 -0,147 0,364 0,092 Morning stiffness (minute) 0,415 -0,082 0,592 -0,054 0,542 -0,062 Tender joint counts 0,046* -0,200 0,099 -0,166 0,361 -0,092 Swollen joint counts 0,109 -0,161 0,227 -0,122 0,522 -0,065 CRP 0,681 -0,042 0,144 0,147 0,076 0,178 ESR 0,952 -0,006 0,330 0,098 0,453 0,076 VAS 0,056 -0,192 0,069 -0,182 0,086 -0,173 PCS 0,013* -0,248 0,013* -0,249 0,034* -0,212 Fatigue Intensity Scale 0,107 -0,162 0,145 -0,147 0,422 -0,081 HADS-Anxiety 0,157 -0,143 0,118 -0,157 0,285 -0,108 HADS-Depression 0,010* -0,256 0,005* -0,282 0,003* -0,293 HADS-Total 0,026* -0,223 0,014* -0,245 0,024* -0,225 HAQ <0,001* -0,264 0,000* -0,287 <0,001* -0,315 DAS28-ESR 0,013* -0,248 0,091 -0,170 0,211 -0,126 DAS28-CRP 0,009* -0,261 0,066 -0,185 0,220 -0,124 PT: pain threshold, BMI: Body mass index, PCS: Pain Catastrophizing Scale, VAS: Visual Analog Scale, HAQ: The health assessment questionnaire *p < 0.05 Reference [1] Bagnato G, De Andres I, Sorbara S, Verduci E, Corallo G, Ferrera A, et al. Pain threshold and intensity in rheumatic patients: correlations with the Hamilton Depression Rating scale. Clinical rheumatology. 2015;34(3):555-61. Disclosure of Interests None declared