Risk of cardiovascular disease with high-dose versus low-dose use of non-steroidal anti-inflammatory drugs in ankylosing spondylitis

Objective To investigate the risk of cardiovascular disease (CVD) associated with increasing dose of a non-steroidal anti-inflammatory drug (NSAID) in patients with ankylosing spondylitis (AS). Methods Using the Korean National Health Insurance database, patients newly diagnosed with AS without prior CVD between 2010 and 2018 were included in this nationwide cohort study. The primary outcome was CVD, a composite outcome of ischaemic heart disease, stroke or congestive heart failure. Exposure to NSAIDs was evaluated using a time-varying approach. The dose of NSAIDs was considered in each exposure period. Cox proportional hazard regression was used to investigate the risk of CVD associated with NSAID use. Results Of the 19 775 patients (mean age, 36 years; 75% were male), 19 706 received NSAID treatment. During follow-up period of 98 290 person-years, 1663 cases of CVD occurred including 1157 cases of ischaemic heart disease, 301 cases of stroke and 613 cases of congestive heart failure. Increasing dose of NSAIDs was associated with incident CVD after adjusting for confounders (adjusted HR (aHR) 1.10; 95% CI 1.08 to 1.13). Specifically, increasing dose of NSAIDs was associated with incident ischaemic heart disease (aHR 1.08; 95% CI 1.05 to 1.11), stroke (aHR 1.09; 95% CI 1.04 to 1.15) and congestive heart failure (aHR 1.12; 95% CI 1.08 to 1.16). The association between NSAID dose and higher CVD risk was consistent in different subgroups. Conclusion In a real-world AS cohort, higher dose of NSAID treatment was associated with a higher risk of CVD, including ischaemic heart disease, stroke and congestive heart failure.