Higher risk of recurrent stroke after early statin discontinuation
Utilization of Statins Beyond the Initial Period After Stroke and 1-Year Risk of Recurrent Stroke
Guidelines recommend statin therapy for patients with a history of ischemic stroke or TIA, but in every-day clinical practice, many high-risk patients are not maintained on statin therapy beyond the first 3 months [1-5]. The effects of discontinuing or reducing statin treatment early after an index ischemic stroke have not been adequately studied.
This study evaluated the effects of statin discontinuation or statin dose reduction on the risk of recurrent stroke in a large, retrospective cohort study, by retrieving all hospitalized patients (≥20 years) with a primary diagnosis of ischemic stroke from January 1, 2001 to December 31, 2012 in the Taiwan National Health Insurance Research Database.
The study population was followed from day 181 after the index stroke for 1 year. Patients with AF, patients not receiving antiplatelet therapy, patients with end-stage renal disease, and patients with a recurrent stroke within 180 days of the index stroke were excluded from the study. The intensity of the statin therapy was defined based on the 2013 ACC/AHA guidelines on the treatment of blood cholesterol .
Patients were categorized into 3 groups:
- Statin discontinuation group: not receiving any statin between day 91 and 180 after the index event
- Statin-reduced group: on low-intensity statin therapy, or change from high-intensity to moderate-intensity statin therapy between day 91 and day 180 after the index event
- Statin-maintained group: patients on high-intensity or moderate-intensity statin therapy between day 91 and day 180 after the index event.
- Among the 45 151 ischemic stroke patients 74.5% were in the statin-maintained group, 7.0% were in the statin-reduced group, and 18.5% were not on any statin therapy.
- In the whole cohort, 2120 recurrent strokes were observed during the 1-year follow-up.
- In multivariable analyses, compared with the statin-maintained group, the discontinuation of statins was associated with an increased hazard of recurrent ischemic or hemorrhagic stroke (6.2% vs. 4.4%; adjHR: 1.42; 95%CI: 1.28-1.57; P<0.0001), whereas the statin-reduced group did not show an additional risk (4.1% vs. 4.4%; adjHR: 0.94; 95%CI: 0.78-1.12; P=0.47).
Compared with the statin-maintained group, the discontinuation of statins was associated with higher risks of:
- ischemic stroke: 5.6% vs. 3.9%; adjusted HR: 1.45; 95%CI: 1.30-1.61; P<0.0001
- all-cause mortality: 1.4% vs. 1.0%; adjusted HR: 1.37; 95%CI: 1.11-1.70; P=0.003
- all major events: 7.8% vs. 5.6%; adjusted HR: 1.38; 95%CI: 1.26-1.51; P<0.0001
- any hospitalization: 31.7% vs. 27.1%; adjusted HR: 1.19; 95%CI: 1.14-1.24; P<0.0001
- Statin discontinuation had a neutral effect on intracerebral hemorrhage and on MI.
- Statin-reduced therapy was not associated with increased risks of ischemic stroke, intracerebral hemorrhage, all-cause mortality, MI, or all major events.
The discontinuation of statin therapy 3 to 6 months after an index ischemic stroke event, was associated with a higher risk of recurrent stroke within 1 year after statin discontinuation. These findings suggest that stroke patients should not discontinue statin therapy, unless there is a serious reason for doing so.