Treatment with statins is not associated with increased risk for intracerebral hemorrhage (ICH) in patients with a history of stroke, and may even decrease the risk for ICH in some of these patients, according to study results published in Stroke.
Although there are conflicting data on the statin-associated risk for ICH among patients with a prior history of stroke and there are insufficient data to recommend restriction on statin use in these patients, many experts still advise against the use of statins in patients with a history of ICH. The goal of the current study was to assess the statin-associated risk for ICH in patients with prior stroke history.
The population-based, propensity score-matched cohort study used data from Danish nationwide registries. The study population included all patients who initiated statin therapy after their first stroke diagnosis and matched 5 nonusers with a history of the same type of stroke. The primary outcome was recurrent stroke, ischemic or hemorrhagic, associated with redemptions of statin prescriptions between 2002 and 2016.
The study cohort included 55,692 participants who initiated statin treatment after a first-time stroke diagnosis (4.9% ICH and 95.1% ischemic stroke), and 65,640 participants who were not treated with statins. The groups had similar characteristics in terms of important covariates and long-term use of antiplatelet and antihypertensive agents.
Among patients with a history of prior ICH, the risk for recurrent ICH was similar for statin users and nonusers (4.0% vs. 5.7%, respectively; hazard ratio 0.90, 95% CI, 0.72-1.12), and the risk was similar throughout the period up to 10 years after initiating the use of statins. Among those with a history of prior ischemic stroke, the risk for ICH was lower in the group of statin-treated patients compared with nonusers (0.6% vs. 0.9%, respectively; adjusted hazard ratio, 0.53; 95% CI, 0.45-0.62).
The researchers noted that these findings were consistent over all times since statin initiation. They also noted that the findings could not be explained by concomitant initiation of other medications relevant to stroke risk, by dilution of treatment effect (resulting from changes over time in exposure status), or by healthy initiator bias.
The study had several limitations including potential time-varying confounding such as a healthy adherer bias; possible healthy initiator bias, as some comorbidities tended to be more common in the nonusers compared with statin users; missing data on severity of first-time stroke; and limitations secondary to collecting information on statin use based on redemptions of prescriptions.
“The risk of ICH is similar for statin users and nonusers when evaluated in individuals with prior ICH and perhaps even reduced in those with prior [ischemic stroke[, although differences in disease severity could play a role,” conclude the researchers.
Ribe AR, Vestergaard CH, Vestergaard M, et al. Statins and risk of intracerebral hemorrhage in individuals with a history of stroke [published online ahead of print March 2, 2020]. Stroke. doi:10.1161/STROKEAHA.119.027301