Background The serum levels of the soluble fractalkine (CX3CL1) play crucial roles in the pathogenesis of rheumatoid arthritis (RA) and neuropsychiatric systemic lupus erythematous. The relationship of CX3CL1 and the activities of daily living (ADL), health-related quality of life (HRQoL) and depression in RA patients were not clear.
Objectives The objective of this study was to analyze the correlation of the serum levels of CX3CL1 with the ADL, HRQoL, and depression in patients with RA.
Methods A total of 161 RA patients were assessed prior to treatment and 30 weeks after initiating the biologic therapy. Infliximab, etanercept, adalimumab, tocilizumab, abatacept, and golimumab were used as the biologic therapies, and the choice of treatment was at the physicians’ discretion. Age, gender, and steroid dosage were recorded for each participant, and the disease activity score (DAS) 28/ESR4, the ADL (modified Health Assessment Questionnaire; mHAQ), the HRQoL questionnaire (Short Form [SF]-36), the depression scale (The Self-rating Depression scale [SDS]) and serum levels of CX3CL1 were evaluated in the patients. The serum level of CX3CL1 was quantified using a commercial ELISA kit according to the manufacturer’s instructions.
Results Patients with lower (<1000 pg/ml, Group 1) and higher titer (>1000, Group 2) basal CX3CL1 levels were compared. The DAS28 score (4.3 ± 1.4, mean ± SD) in Group 1 was lower than that in Group 2 (4.9 ± 1.8) (p<0.05), and the mHAQ score (0.37 ± 0.43) in Group 1 was lower than that in Group 2 (0.54 ± 0.50) (p<0.05) at baseline. After 30 weeks of treatment, the mHAQ score was lower in Group 1 (0.14 ± 0.26) than in Group 2 (0.38 ± 0.47) (p<0.005), and the SDS score was lower in Group 1 (35.9 ± 9.1) than in Group 2 (40.3 ± 11.0) (p<0.05). The SDS score at baseline and the DAS28 score were not significantly improved. Although there was a direct correlation between the mHAQ and CX3CL1 (p<0.05) at baseline, no significant improvements in the DAS28 and SDS scores were observed. In addition, the age, gender, and steroid dosage were not significantly different between Groups 1 and 2.
Conclusions In this study, a higher titer of CX3CL1 serum levels led to the aggravation of not only the disease activity and ADL at baseline but also the ADL and depression after the biologics treatment. The serum levels of CX3CL1 may be more closely related to ADL in RA patients.
Disclosure of Interest Y. Miwa Grant/research support from: Tanabemitsubishi, Wyeth, Abbott, Eizai, Chugai, S. Isojima: None Declared, M. Umemura: None Declared, H. Tsukamoto: None Declared, T. Tokunaga: None Declared, H. Furuya: None Declared, R. Yanai: None Declared, K. Otsuka: None Declared, R. Takahashi: None Declared, K. Wakabayashi: None Declared, N. Yajima: None Declared, T. Kasama: None Declared, M. Hosaka: None Declared