Comparison of clinical characteristics between patients with axial spondyloarthritis with and without acute anterior uveitis: a multicentre study of the Chinese Spondyloarthritis Registry.

OBJECTIVES: This study explores the clinical characteristics associated with the occurrence of acute anterior uveitis (AAU) in patients with axial spondyloarthritis (axSpA) within a large, multicentre database. METHODS: This observational, cross-sectional study of patients with axSpA used data from the Chinese Spondyloarthritis Registry between August 1, 2018, and March 31, 2020. The demographic and clinical features of patients with and without AAU were compared. Univariate and multivariate analyses were performed to determine the association between variables and uveitis. RESULTS: A total of 4304 patients were included in this study. The prevalence of AAU in patients with axSpA was 10.59%. Multivariate logistic regression analysis revealed a positive correlation between AAU and age at diagnosis (odds ratio [OR], 1.026; p<0.001), disease duration (OR, 2.117; p<0.001), current or past Achilles tendinitis (OR, 1.692; p<0.001), current or past dactylitis (OR, 1.687; p=0.002), current or past psoriasis (OR, 3.932; p<0.001), presence of human leukocyte antigen-B27 (HLA-B27) (OR, 2.787; p<0.001), and a good response to non-steroidal anti-inflammatory drugs (NSAIDs) (OR, 1.343; p=0.027). CONCLUSIONS: AAU was the most common extra-articular manifestation in the Chinese Spondyloarthritis Registry. In Chinese patients with axSpA, older age at diagnosis, longer disease duration, presence of HLA-B27, current or past Achilles tendinitis, current or past dactylitis, current or past psoriasis, and a good response to NSAIDs were positively associated with AAU.

Anemia and Low Body Mass Index in Axial Spondyloarthritis: Results from ChinaSpA, the Chinese Spondyloarthritis Registry.

INTRODUCTION: Anemia and malnutrition are recognized indicators of suboptimal physical condition in chronic inflammatory diseases. This study aimed to examine the association between anemia, low body mass index (BMI), and clinical outcomes in axial spondyloarthritis (axSpA). METHOD: This cross-sectional analysis utilized data from the multicenter ChinaSpA cohort. A total of 4146 participants with axSpA were categorized into four groups based on BMI and hemoglobin levels: those with both anemia and low BMI, those with anemia only, those with low BMI only, and those with neither condition. Logistic regression analyses were performed to analyze the association between anemia, low BMI, inflammation status, functional impairment, and disease activity. RESULTS: Anemia was present in 13.94%, low BMI in 11.99%, and both conditions in 2.15% of axSpA participants. Those with both anemia and low BMI showed significantly higher levels of inflammation (hypersensitive C-reactive protein [hsCRP] 30.60 mg/L vs. 8.44 mg/L), functional impairment (Bath Ankylosing Spondylitis Functional Index [BASFI] 3.80 vs. 2.10), and disease activity (Bath Ankylosing Spondylitis Disease Activity Index [BASDAI] 4.52 ± 2.04 vs. 3.67 ± 2.21; Ankylosing Spondylitis Disease Activity Score calculated with C-reactive protein [ASDAS_CRP] 3.51 ± 1.10 vs. 2.62 ± 1.21) compared to those without these conditions. After adjusting for sex and age, significant associations were observed between elevated hsCRP levels and the presence of low BMI (odds ratio [OR] 1.44, 95% CI 1.17-1.78), anemia (OR 1.91, 95% CI 1.56-2.32), and their concurrent presence (OR 3.59, 95% CI 2.22-5.80). Similarly, increased BASFI was significantly associated with low BMI (OR 1.57, 95% CI 1.25-1.97), anemia (OR 1.47, 95% CI 1.19-1.80), and their combination (OR 3.11, 95% CI 2.02-4.78). CONCLUSION: All-cause anemia and low BMI are prevalent complications in patients with axSpA, exhibiting a significant correlation with elevated inflammation status and functional impairment. The simultaneous occurrence of anemia and low BMI particularly exacerbates clinical outcomes, emphasizing the critical role of comprehensive nutritional assessment and management in the therapeutic strategy for axSpA.