Background This study aimed to explore whether
statins reduce radiation-induced vascular complications in
cancer patients postradiotherapy to the thorax, head, and neck. Methods and Results We conducted a retrospective cohort study within a provincial linked database of 5718 cardiac patients with thorax and head or
neck cancer having undergone
radiotherapy between 2000 and 2011. One thousand five hundred fifty-two patients were identified as nonstatin users and 4166 as
statin users. The primary outcome of interest was the composite of cerebrovascular (
transient ischemic attack, and fatal or nonfatal
stroke) or cardiovascular events (fatal or nonfatal
myocardial infarction). Time-dependent Cox proportional hazard analyses were performed. The crude event rate was 10.31% for nonusers and 9.03% for
statin users (hazard ratio of 0.92 [95% CI 0.76-1.10, P=0.3451]), over a mean time to event/censoring of 534±687 days for nonusers and 594±706 days for the
statin users. After adjusting for age, sex, prior history of
stroke/
transient ischemic attack or
myocardial infarction,
diabetes mellitus,
dyslipidemia,
atrial fibrillation,
chronic kidney disease,
heart failure, and
hypertension,
statin use postradiotherapy was associated with a nonsignificant 15% relative risk reduction, but a strong trend toward reducing the primary outcome (hazard ratio=0.85 95% CI 0.69-1.04, P=0.0811). The use of
statins was associated with a significant reduction of 32% for the outcome of
stroke alone (hazard ratio=0.68, 95% CI 0.48-0.98, P=0.0368). Conclusions
Statin use post
radiation therapy was associated with a significant reduction in
stroke, with a trend toward significantly reducing cardiovascular and cerebrovascular events.