Effectiveness of thalidomide for ankylosing spondylitis: a meta-analysis of randomized controlled trials in China

Several studies have demonstrated the benefits of thalidomide as a treatment for patients with ankylosing spondylitis (AS); however, published literature reported controversial results. We conducted a meta-analysis to systematically evaluate the efficacy of thalidomide in AS patients. PubMed, Embase, Cochrane Library, Web of Science, Wanfang Data, and China National Knowledge Infrastructure (CNKI) were searched for relevant studies. The Q test and I² statistic were used to examine between-study heterogeneity. Fixed- or random-effects models were selected based on study heterogeneity. The risk difference (RD), absolute risk reduction (ARR), and weighted mean difference (WMD) with 95% confidence intervals (CI) were pooled for dichotomous or continuous data, as appropriate. Sensitivity analyses, funnel plots, and the Begg's tests were also performed. Overall, 19 trials with 1471 patients were included. The effectiveness of thalidomide alone and combined with other drugs was significantly higher than the control group, and the pooled RDs were 0.15 (95% CI: 0.10-0.20, I² = 0%) and 0.20 (95% CI: 0.14-0.25, I² = 13.4%), respectively. Thalidomide treatment yielded significant improvements in secondary outcomes for patients with AS. The adverse reaction rate for thalidomide alone was low than that for the control group (ARR = 0.08, 95% CI: 0.01-0.15, I² = 0.0%), while there was no significant difference in the safety between the group in which thalidomide was combined with other drugs and the control (ARR = 0.03, 95% CI: - 0.04-0.10, I² = 41.1%). The findings suggest that thalidomide improves the effectiveness of AS treatment, which should be considered by physicians. However, owing to the inclusion of several low-quality and Chinese studies, additional rigorous randomized controlled trials (RCTs) are needed in the future to confirm the results of this meta‑analysis.