Cancer risks in patients with ankylosing spondylitis and the effects of biologic agents: a population-based study

Abstract

Abstract Objective The objective of this study was to conduct a population-based analysis of the malignancy risks of patients with AS. Methods A total of 1796 patients with AS and 7184 age- and sex-matched controls (1:4 ratio) were selected from the Korea National Health Insurance Service–National Sample Cohort database. Data of patients diagnosed with AS (code M45) according to the International Classification of Diseases (ICD) 10th edition, between 2002 and 2019, were reviewed. These data were extracted based on the ICD codes assigned to cancer patients. Results Cancer developed in 168/1796 patients (9.3%) after the AS diagnosis. After adjusting for confounders, the cancer risk of patients with AS was not significantly increased compared with that of controls [adjusted hazard ratio (HR): 1.1; 95% CI: 0.93–1.31]. However, the risks for upper gastrointestinal (GI) cancer (adjusted HR: 1.51; 95% CI: 1.07–2.12) and haematologic malignancy (adjusted HR: 2.36; 95% CI: 1.2–4.65) were significantly higher in patients with AS than in controls. There were no significant differences in the risks for other major cancers between patients with AS and controls. Regarding medication for AS, the HR of upper GI cancer was higher in patients with AS compared with controls (adjusted HR: 1.51; 95% CI: 1.00–2.29). Conclusion The overall cancer risk in patients with AS was not significantly different compared with that in the controls. However, while the effect of NSAIDs on upper GI cancer cannot be ruled out, patients with AS exhibited a significant increase in the risk of both upper GI cancer and haematologic malignancy.