European Journal of Rheumatology
Original Article

Serum interleukin-6 in seropositive rheumatoid arthritis and response to tocilizumab: An observational study

1.

Department of Rheumatology, Command Hospital (Eastern Command), Alipore, Kolkata, India

2.

Manipal Hospital, Sector 6, Dwarka, New Delhi, India

3.

Department of Rheumatology, Army Hospital Research and Referral, Delhi, India

4.

Department of Rheumatology, Command Hospital (Southern Command), Pune, India

5.

Department of Medicine, Sree Balaji Medical College and Hospital, Chrompet, Chennai, India

6.

Public Health Foundation of India, Plot 47, Sector 44, Gurgaon, India

7.

Department of Rheumatology, Command Hospital (Central Command), Lucknow, India

Eur J Rheumatol 2022; 9: 26-30
DOI: 10.5152/eurjrheum.2021.20202
Read: 634 Downloads: 393 Published: 01 January 2022

Objective: There is no clinically useful biomarker as a predictor of response to any class of biological disease-modifying antirheumatic drugs (bDMARD). Serum interleukin-6 (IL-6) has a major role in the pathogenesis of rheumatoid arthritis (RA) and its serum level in patients of RA may predict response to treatment with IL-6 receptor (IL-6R) antagonist tocilizumab.

Methods: Biological DMARD naïve patients of seropositive RA, fulfilling American College of Rheumatology/European League Against Rheumatism classification criteria 2010, were treated with 06 doses of tocilizumab (8mg/kg) at monthly interval. Baseline and post-treatment serum IL-6 levels were measured and correlated with response to treatment measured by disease activity score-28 joints erythrocyte sedimentation rate (DAS28 ESR) after treatment.

Results: The study included 34 patients and 26 (70%) of them achieved DAS-28 remission (DAS28 ESR < 2.6). The baseline serum IL-6 did not correlate with post-treatment DAS28 ESR (R −0.197, P = .264). Though, statistically not significant (P = .085) more patients with comparatively lower baseline serum IL-6 attained DAS28 remission (16 out of 17, P = .085). There was an increase in the serum IL-6 level (median 40.5pg/ml [IQR 130.2] to 72.6pg/ml [IQR 162.5]) after tocilizumab treatment and the change in IL-6 level also did not correlate with post-treatment DAS28 ESR (R −0.240, P = .172).

Conclusion: Higher number of patients with comparatively lower serum IL-6 level attained DAS28 remission in this study; however, it was not statistically significant. It requires further evaluation in larger studies to make any conclusion on the role of serum IL-6 as a predictor of response to tocilizumab in seropositive RA.

Cite this article as: Kumar A, Bhakuni DS, Kartik S, et al. Serum interleukin-6 in seropositive rheumatoid arthritis and response to tocilizumab: An observational study. Eur J Rheumatol. 2021;9(1):26-30.

Files
EISSN 2148-4279