Case-control study examining the association between allopurinol use and ischemic cerebrovascular disease

Few studies focus on the relationship between allopurinol and ischemic cerebrovascular disease. The goal of the study was to investigate the association of long-term therapy of allopurinol with the first-time attack of ischemic cerebrovascular disease in Taiwan. We performed a case-control study using the database of the Taiwan National Health Insurance Program. The case group included 14,937 subjects aged 20-84 years with the first-time attack of ischemic cerebrovascular disease from 2000 to 2013. The control group included 14,937 sex-matched and age-matched subjects aged 20-84 years without any type of cerebrovascular disease. Ever use of allopurinol was defined as subjects who had at least a prescription for allopurinol before the index date. The OR and the 95% CI for ischemic cerebrovascular disease associated with allopurinol use were measured by the multivariable logistic regression model. The adjusted OR of ischemic cerebrovascular disease was 0.992 (95% CI 0.989 to 0.996) for subjects with increasing cumulative duration of allopurinol use for every 1 month, compared with never use. In a further analysis, the adjusted OR of ischemic cerebrovascular disease was 0.74 (95% CI 0.57 to 0.96) for cumulative duration of allopurinol use >3 years, compared with never use. Our findings suggest that lone-term therapy of allopurinol >3 years is associated with decreased risk of the first-time attack of ischemic cerebrovascular disease, compared with no allopurinol therapy.