A brain aneurysm is a bulge that forms in the wall of a brain artery, after the artery wall weakens. People usually find out they have a brain aneurysm by chance — when they have an MRI for another medical condition or when they’re being screened because they have a family history of aneurysms, for example. In most people, brain aneurysms don’t cause symptoms, but if they grow large and rupture, they’re fatal in about 40 percent of cases, according to the Brain Aneurysm Foundation. Among those who survive, approximately two-thirds end up with some long-lasting neurological damage. In a study published in May 2018 in the journal Stroke, researchers examined the medical records of 4,701 patients who had been diagnosed with one or more brain aneurysms — either ruptured or nonruptured ones — between 1990 and 2016. The researchers also looked at the patients’ cholesterol levels and statin use. It turned out that those who were taking a cholesterol-lowering statin had a 42 percent lower risk of having a brain aneurysm rupture. Those with higher HDL levels also had a significantly lower risk. The theory is that damage to the cells in the inner lining of blood vessels (what’s called the endothelium), along with oxidative stress and inflammation, “contribute to the formation and rupture of aneurysms,” explains senior author Rose Du, MD, PhD, an associate professor of neurosurgery at Harvard Medical School and director of cerebrovascular surgery at Brigham and Women’s Hospital in Boston. By enhancing endothelial function and reducing oxidative stress and inflammation in the artery wall, statins “could potentially halt the progression and eventual rupture of aneurysms,” Dr. Du adds. The study didn’t investigate whether the duration of statin use or the dose taken played a role in preventing brain aneurysms from rupturing. But “my suspicion would be that the longer the sustained use, the lower the risk,” says study coauthor Scott T. Weiss, MD, a professor of medicine at Harvard Medical School. Also, “I would suspect that whatever the effective dose is to lower LDL cholesterol and increase the HDL, or good, cholesterol would have this effect.” While the results are certainly promising, more research — in the form of randomized, controlled studies — needs to be done to demonstrate the efficacy of statins as a treatment for brain aneurysms, says Du. But if the results are confirmed, statins could become a game-changing treatment for patients with brain aneurysms. “Currently, there is no medical therapy for aneurysms — management of aneurysms consists of observation versus some form of invasive treatment [such as surgery],” Du explains. “Being able to decrease the risk of an aneurysm rupture or to halt its progression with a medical treatment such as statins would change the way we manage aneurysms — by increasing the number of patients who can be safely observed and decreasing the number of patients who need to undergo invasive treatment.”
