The purpose of this study was to compare the serum interleukin (IL)-23 levels between rheumatoid arthritis (RA) patients and healthy controls and to determine the correlation of IL-23 levels with disease activity, joint damage and functional disability in RA. Serum samples were obtained from 45 patients with RA and 45 healthy controls. The enzyme-linked immunosorbent assay method was used for quantitative analysis of IL-23. All the RA patients were assessed for disease activity based on the 28-joint disease activity score, joint damage based on modified Sharp score, and functional ability using the Health Assessment Questionnaire-Disability Index. The mean serum IL-23 level was much higher among the RA patients (24.50 ± 13.98 pg/mL) compared to the controls (5.98 ± 3.40 pg/mL; p < 0.01). There was a significant positive relationship between IL-23 levels and disease activity and questionnaire scores (p = 0.003 and 0.020, respectively). On logistic regression analysis, IL-23 levels were significantly higher in patients with moderate to high disease activity (p = 0.008, odds ratio = 1.073, 95% confidence interval = 1.019-1.130) and patients with significant functional disability (p = 0.008, odds ratio = 1.085, 95% confidence interval = 1.021-1.153). RA patients have significantly higher levels of serum IL-23. The IL-23 levels correlate well with disease activity and functional disability but not with radiographic joint damage.
Study site: Rheumatology clinic, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM)
OBJECTIVE:
To assess the relationship between the HLA-DRB1 genes with disease severity as assessed by radiological erosions in Malaysian patients with rheumatoid arthritis (RA).
METHODS:
In this cross-sectional study, we studied 61 RA patients who fulfilled the ACR criteria for the diagnosis of RA. HLA-DRB1 genotyping was performed by sequence specific primer (SSP) - PCR. Radiological grading and erosive score of the hands and wrists was calculated according to the Larsen-Dale method. Demographic data and treatment given to the patients were obtained from their case records.
RESULTS:
Fifty-six females and five males were studied from three ethnic groups. In 57 patients with erosions, rheumatoid factor was detected in 80%, HLA-DR4 in 40%, HLA-DRB1*0405 in 24% and shared epitope (SE) in 31%. The median delay in starting DMARDs was 24 months. The presence of rheumatoid factor, HLA-DR4 and HLA-DRB1*0405 were not significantly associated with a worse erosive score. Patients who possessed the SE had a higher erosive scores, compared to those who did not (p = 0.05). Concurrently, a delay in starting DMARD was associated with a high erosive score (p = 0.023, r = 0.348). However, after adjustment for the delay in starting DMARD, SE was no longer significantly associated with the erosive score.
CONCLUSIONS:
In these patients, the delay in starting DMARDs had a greater influence on the erosive score than SE alone. Whilst we cannot discount the contribution of the SE presence, we would advocate early usage of DMARDs in every RA patient to reduce joint erosions and future disability.