Background — Ankylosing spondylitis (AS) is a chronic inflammatory arthritis affecting the spine in young adults. It is associated with excess cardiovascular and cerebrovascular morbidity.
Objective — To determine whether patients with AS are at increased risk for cardiovascular and cerebrovascular mortality.
Design — Population-based retrospective cohort study using administrative health data.
Setting — Ontario, Canada.
Patients — 21 473 patients with AS aged 15 years or older and 86 606 comparators without AS, matched for age, sex, and location of residence.
Measurements — The primary outcome was a composite of cardiovascular and cerebrovascular death. Hazard ratios (HRs) for vascular death were calculated, adjusted for history of cancer, diabetes, dementia, inflammatory bowel disease, hypertension, chronic kidney disease, and peripheral vascular disease and, among those aged 66 years or older, relevant drug therapies. Independent risk factors for vascular mortality were identified in patients with AS.
Results — The mean age of patients with AS was 46 years, and 53% were male. Patients and comparators were followed for 166 920 and 686 461 patient-years, respectively. Adjusted HRs for vascular death in AS were 1.36 (95% CI, 1.13 to 1.65) overall, 1.46 (CI, 1.13 to 1.87) in men, and 1.24 (CI, 0.92 to 1.67) in women. Significant risk factors for vascular death were age; male sex; lower income; dementia; chronic kidney disease; peripheral vascular disease; and, among patients aged 65 years or older, lack of exposure to nonsteroidal anti-inflammatory drugs and statins.
Limitation — Diagnosis codes for AS were not validated in Ontario.
Conclusions — Ankylosing spondylitis is associated with increased risk for vascular mortality. A comprehensive strategy to screen and treat modifiable vascular risk factors in AS is needed.