Abstract
AIM: Posterior circulation stroke (PCS) has different clinical features and prognosis compared with anterior circulation stroke (ACS), and whether the effect of statin therapy on stroke prevention differs according to infarction location remains unclear. This post hoc analysis of the J-STARS study aimed to compare the usefulness of statin at different infarction locations (i.e., ACS and PCS). METHODS: In the J-STARS study, 1578 patients were randomly assigned to the pravastatin or control group. The subjects were divided into two subgroups (ACS and PCS groups) based on the arteries responsible for the infarction. Cox proportional hazards models were used to investigate whether the all stroke recurrence rate was different between the ACS and PCS groups. RESULTS: The PCS group (n=499) had a significantly higher prevalence of diabetes than the ACS group (n=1022) (30.7% vs. 19.8%, P＜0.001). During the follow-up (4.9±1.4 years), the incidence of all stroke was significantly lower in the pravastatin group than in the control group among patients with PCS (adjusted hazard ratio [HR] 0.46, 95% confidence interval [CI] 0.25-0.83, P=0.009); however, the stroke recurrence rates were not significantly different between both groups among patients with ACS (adjusted HR 1.32, 95% CI 0.93-1.88,P=0.123). A significant interaction between the ACS and PCS groups in terms of pravastatin effects was noted (P=0.003 for interaction). CONCLUSIONS: Pravastatin significantly reduced the recurrence rate of all stroke among patients with PCS. Thus, the effect of statin on the recurrence of stroke may differ according to infarction location.