Effect of Statin Withdrawal on Carotid Arterial Distensibility

Background: Statin is widely used in preventing cerebrovascular disease.Despite reliable evidence from clinical trials, statin is frequently discontinued in clinical practice.We investigated the effect of statin withdrawal on carotid arterial distensibility (CAD).Methods: Twenty-one subjects without cerebrovascular disease (mean age, 61 years; seven men) who wanted to discontinue statin were included in this study.CAD was assessed five times in each subject by carotid duplex ultrasound: the first and second examinations were performed during statin maintenance, while the subsequent examinations were performed 2, 7, and 30 days after statin discontinuation.CAD was measured by strain calculated as (systolic diameter-diastolic diameter) / diastolic diameter and stiffness (β) as ln (systolic blood pressure [BP] / diastolic BP) / strain.Statistical difference in values measured at each time point was evaluated using the Friedman and Wilcoxon's tests.Results: CAD decreased after statin discontinuation as demonstrated by the comparison of strain (Friedman test, p=0.007) and β (p<0.001).Compared with the baseline mean±standard error, strain did not change during statin use (8.0±0.5% at baseline, 7.9±0.5% on the 2nd day, p=0.386) but decreased after statin discontinuation (6.6±0.8% on the 2nd day, p=0.002; 6.9±0.6% on the 7th day, p=0.017).β increased after statin discontinuation (11.7±1.5 on the 2nd day, p=0.001; 9.7±0.9 on the 7th day, p=0.011) compared with that at baseline (7.8±2.3).Strain and β measured 30 days after withdrawal were not different from baseline values.Conclusion: Statin discontinuation results in transient decrease in CAD.Further studies are required to investigate whether this association would have clinical significance.