Physical function and sex differences in radiographic axial spondyloarthritis: a cross-sectional analysis on Bath Ankylosing Spondylitis Functional Index.

BACKGROUND: Physical function is an important determinant of health-related quality of life in radiographic axial spondyloarthritis patients (r-axSpA). To improve the basis of effective healthcare efforts, we aimed to investigate which demographic and disease-related factors that influence Bath Ankylosing Spondylitis Functional Index (BASFI) in r-axSpA patients overall and stratified by sex. Furthermore, we sought to explore differences between sexes regarding separate BASFI questions and also to explore which factors that may contribute to these differences. METHODS: This observational cross-sectional study included patients fulfilling the modified New York criteria for Ankylosing Spondylitis. Patients were assessed with 66/68 joint count and Bath Ankylosing Spondylitis Metrology Index (BASMI) measurements. Lateral X-rays were performed for Modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS). Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Ankylosing Spondylitis Disease Activity Score (ASDAS)-C-Reactive Protein (CRP), and BASFI were registered. Multivariable linear regression analyses were used to investigate which factors that associate with BASFI. RESULTS: A total of 353 r-axSpA patients were included, mean age 52.2 ± 12.7 years, 62.3% males. No significant sex difference was seen in BASFI scores (2.7 ± 2.0 in males vs 2.9 ± 2.1 in females). Age, body mass index, ASDAS-CRP, BASMI or mSASSS, fatigue, and tenderness were found to associate independently with BASFI in different models (R2 0.53-0.63). Investigation of separate BASFI questions revealed that the ability to look over shoulder was worse in males than females (mean 4.43 ± 3.37 vs 3.74 ± 3.06, p = 0.05) and most strongly correlated with mSASSS and BASMI among separate BASFI questions (r = 0.53, p < 0.001; r = 0.62, p < 0.001). The ability to climb stairs was worse in females than males (mean 2.49 ± 2.77 vs 1.54 ± 2.32, p < 0.001). CONCLUSIONS: No difference between male and female r-axSpA patients was seen in BASFI despite significant sex differences in BASMI, mSASSS, and CRP levels. Our results underline the impact of fatigue and tenderness on BASFI. The ability to climb stairs without a handrail was scored worse among females compared to males. Furthermore, the ability to look over the shoulder was worse in males than females and closely related to spinal mobility and structural spinal changes.

Blood PD-1+TFh and CTLA-4+CD4+ T cells predict remission after CTLA-4Ig treatment in early rheumatoid arthritis.

OBJECTIVE: Treatment with CTLA-4Ig blocks T-cell activation and is clinically effective in RA. However, it is unknown if specific CD4+ T-cell subsets in blood at baseline predict remission after CTLA-4Ig, or other biological treatments with different modes of action, and how treatment affects CD4+ T cells in patients with untreated early RA (eRA). METHODS: This study included 60 patients with untreated eRA from a larger randomized trial. They were treated with methotrexate combined with CTLA-4Ig (abatacept, n = 17), anti-IL6 receptor (tocilizumab, n = 21) or anti-TNF (certolizumab-pegol, n = 22). Disease activity was assessed by clinical disease activity index (CDAI), DAS28, swollen joint counts, tender joint counts, CRP and ESR. The primary outcome was CDAI remission (CDAI ≤ 2.8) at week 24. Proportions of 12 CD4+ T-cell subsets were measured by flow cytometry at baseline and after 4, 12 and 24 weeks of treatment. RESULTS: In patients treated with CTLA-4Ig, the proportions of PD-1+TFh and CTLA-4+ conventional CD4+ T cells at baseline predicted CDAI remission at week 24. CD4+ T-cell subset proportions could not predict remission after treatment with anti-IL6R or anti-TNF. The percentage of regulatory T cells (Tregs) expressing CTLA-4 decreased in all treatment arms by 24 weeks, but only CTLA-4Ig treatment significantly reduced the proportions of Tregs and PD-1+T follicular helper (TFh) cells. CONCLUSION: These findings indicate that circulating proportions PD-1+TFh and CTLA-4+ conventional CD4+ T cells at baseline may serve as predictive biomarkers for remission in early RA after CTLA-4Ig treatment.

Circulating T helper and T regulatory subsets in untreated early rheumatoid arthritis and healthy control subjects.

The pathogenic role and frequency of T cell subtypes in early rheumatoid arthritis are still unclear. We therefore performed a comprehensive analysis of the circulating T cell subtype pattern in patients with untreated early rheumatoid arthritis compared to healthy control subjects. Peripheral blood mononuclear cells were obtained from 26 patients with untreated early rheumatoid arthritis and from with 18 age- and sex-matched healthy control subjects. T helper cell types Th0, Th1, Th2, Th17, and Th1/17 and nonclassic T helper subsets were defined by flow cytometry based on the expression of chemokine receptors CCR4, CCR6, and CXCR3. Regulatory T cells were defined by expression of CD25+ CD127low and also FOXP3 CXCR5+ cells among regulatory and nonregulatory T cells were defined as T follicular regulatory and T follicular helper cells, respectively. The phenotype of T cell subsets was confirmed by transcription factor and cytokine secretion analyses. Multivariate discriminant analysis showed that patients with untreated early rheumatoid arthritis were segregated from healthy control subjects based on the circulating T cell subset profile. Among the discriminator subsets, CCR4+CXCR3- (Th2 and Th17), CTLA4+ and FOXP3+ subsets were present in significantly higher frequencies, whereas CCR4- (Th1/Th17, CCR6+CCR4-CXCR3-, and Th1) subsets were present in lower frequencies in patients with untreated early rheumatoid arthritis compared with healthy control subjects. The proportions of Th2 and Th17 subsets associated positively with each other and negatively with the CXCR3+/interferon γ-secreting subsets (Th1 and Th1/Th17) in patients with untreated rheumatoid arthritis. The proportions of Th2 cells increased with age in patients with untreated early rheumatoid arthritis and healthy control subjects. The dominance of circulating CCR4+CXCR3- T helper subsets (Th2 and Th17) in untreated early rheumatoid arthritis point toward a pathogenic role of these cells in early stages of the disease.