Carotid Intima-Media Thickness in Patients with Ankylosing Spondylitis: A Systematic Review and Updated Meta-Analysis

AIM: Inflammatory arthritis (IA) diseases are relevant with subclinical atherosclerosis, but the data in ankylosing spondylitis (AS) were inconsistent. Therefore, we performed this meta-analysis to explore the relationship between the marker of subclinical atherosclerosis (carotid intima-media thickness (IMT)) and AS. METHODS: We performed a systematic literature review using PubMed, Web of Science, Chinese National Knowledge Infrastructure (CNKI) and Chinese Biomedical Database (CBM) databases up to March 2018. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated to assess the association between carotid IMT and AS. Subgroup analysis, sensitivity analysis, and meta-regression were applied to explore the sources of heterogeneity, and publication bias was calculated to access the quality of pooled studies. RESULTS: A total of 24 articles were collected. The carotid IMT was significantly increased in AS compared with healthy controls (SMD=0.725, 95% CI=0.443-1.008, p＜0.001). Subgroup analyses showed the Bath Ankylosing Spondylitis Activity Index (BASDAI) was the source of heterogeneity. Notably, IMT was not significantly increased in those studies that included ＞50% patients treated with anti-TNF. Meta-regression revealed severe inflammation status (BASDAI and C-reactive protein (CRP)) could significantly impact carotid IMT in AS. CONCLUSIONS: Carotid IMT was significantly increased in patients with AS compared with healthy controls, which suggested subclinical atherosclerosis is related to AS.