Statins, especially high-intensity statins, could reduce the risk of a composite of death, stroke, acute coronary syndrome, or major bleeding as compared to a placebo in patients with acute ischemic stroke and atrial fibrillation. The observational study that was published in the Journal of the American Heart Association highlights the need for a further randomized control trial to further explore this observation.
With the increasing prevalence of atrial fibrillation (AF) comes an increasing number of patients who have AF who are diagnosed with a stroke. There is a need to improve the prognosis of patients with AF diagnosed with a stroke. Statins have previously been explored as a potential treatment option in these patients. There is evidence to suggest better outcomes in patients with non-cardioembolic strokes presumed to be of an atherosclerotic origin. While statin therapy in patients with AF and stroke have shown to be associated with improved survival outcomes, whether this differs by statin intensity is not known.
Using data from the prospective registry, K-ATTENTION (Korean Atrial Fibrillation Evaluation Registry in Ischemic Stroke Patients), the investigators identified patients with atrial fibrillation and acute ischemic stroke. Patients with no data regarding statins, who died during the index hospitalization or were followed for less than 3 months were excluded. Patients were then divided into three groups based on their statins status (no statins, low to a moderate-intensity statin, and high-intensity statin). Patients were followed up over three years. The outcome of interest was the occurrence of a net adverse clinical and cerebral event (NACCE, a composite of death from any cause, stroke, acute coronary syndrome, or major bleeding).
Of the 3,213 patients in the registry, a total of 2,153 had atrial fibrillation and an acute ischemic stroke and were enrolled in the study. Of the patients in the study, 26.7% were not on a statin, 47.0% received a low or moderate-intensity statin and 26.3% received a high-intensity statin. As compared to patients who were not on statins, those on a low-moderate intensity statin had better outcomes (HR 0.51, 95% CI 0.40-0.66). High-intensity statins were also associated with a lower risk of NACCE as compared to those who were on a low or moderate-intensity statin (HR 0.76, 95% CI 0.59-0.96). When looking at the composite outcome, the rates of recurrent stroke or acute coronary syndrome were not different between the two groups. The rate of major bleeding was significantly lower in the low to moderate intensity statin users as compared to those who were not on statins. While the rate of major bleeding was also lower in the high-intensity statin group as compared to the no statin group, this did not reach statistical significance. The beneficial effects of statin were the same amongst all subgroups (this included age, sex, baseline HAS-BLED score, baseline CHADS-VASc score and in those with clear atherosclerotic cardiovascular disease).
The study highlights the beneficial effect of statin use in patients with AF and an ischemic stroke. Additionally, the investigators demonstrated that high-intensity statin use is associated with better outcomes as compared to low-moderate intensity statins and no statins. While current guidelines recommend the use of statins in patients in patients with atherosclerotic cardiovascular disease, it is still unclear whether statin therapy is effective in AF patients with ischemic strokes. This is especially true considering that patients with AF tended to be excluded from the trials that formed the basis of this recommendation. The investigators here were able to demonstrate that statin therapy had a beneficial effect, regardless of whether or not the patient had clinically overt signs of ASCVD. However, this study does have its limitations. This was a cohort study with a retrospective analysis of prospective data with no randomization. The findings may be influenced by confounding. Additionally, compliance with statin therapy was not thoroughly assessed. Regardless, the findings warrant a prospective randomized controlled trial to determine whether high-intensity statins truly have a beneficial effect in patients with AF and an acute ischemic stroke.