Time and dose-dependent effect of systemic glucocorticoids on major adverse cardiovascular event in patients with rheumatoid arthritis: a population-based study.

OBJECTIVES: Cardiovascular event (CVE) risk in rheumatoid arthritis (RA) was increased by glucocorticoids (GC) use. Whether there is a threshold dose and duration of GC use beyond which will increase CVE rate remains controversial. We studied the time-varying effect of GC and its dose on the risk of incident major adverse cardiovascular events (MACE) in patients with RA. METHODS: Patients with RA without MACE at baseline were recruited from a Hong Kong citywide database from 2006 to 2015 and followed till 2018. The primary outcome was the first occurrence of an MACE. Cox regression and inverse probability treatment weighting analyses with time-varying covariates were used to evaluate the association of GC and MACE, adjusting for demographics, traditional CV risk factors, inflammatory markers and the usage of antirheumatic drugs. RESULTS: Among 12 233 RA patients with 105 826 patient-years of follow-up and a mean follow-up duration of 8.7 years, 860 (7.0%) developed MACE. In the time-varying analyses after controlling for confounding factors, a daily prednisolone dose of ≥5 mg significantly increased the risk of MACE (erythrocyte sedimentation rate model: HR 2.02, 95% CI 1.72 to 2.37; C reactive protein model: HR 1.87, 95% CI 1.60 to 2.18), while a daily dose below 5 mg was not associated with MACE risk, compared with no GC use. In patients receiving daily prednisolone ≥5 mg, the risk of incident MACE was increased by 7% per month. CONCLUSIONS: GC was associated with a duration and dose-dependent increased risk of MACE in patients with RA. Very low dose prednisolone (<5 mg daily) did not appear to confer excessive CV risk.