Study: Dual Blood Thinners Are Under-Prescribed After Minor Stroke

According to a recent study, fewer than half of patients were prescribed dual blood-thinning therapy after a minor stroke or transient ischemic attack (TIA), despite evidence that starting 2 anti-platelet blood thinning medications may reduce the short-term risk of recurrent stroke. The treatment regimen was particularly under-prescribed among women, according to the findings presented at the American Stroke Association’s International Stroke Conference 2023.

Blood thinners, such as aspirin and clopidogrel, prevent platelets from sticking together and forming blood clots. Prescribing 2 of these medications at the same time is known as dual antiplatelet therapy (DAPT), which has been shown to reduce the short-term risk of another, potentially more serious, stroke in patients who have recently had a minor stroke or TIA.

TIA is caused by a clot temporarily blocking blood flow to the brain, although symptoms usually last only a few minutes and result in no permanent brain injury or physical disability.

“All stroke survivors, regardless of sex, should receive optimal proven medications for stroke prevention including DAPT when medically appropriate,” said lead author Jonathan Solomonow, MD, chief resident in neurology at the University of Maryland Medical Center in Baltimore, in a press release.

In their new study, investigators reviewed the electronic health records of 2953 adults admitted to any hospitals in the University of Maryland Stroke Clinical Network, which includes 9 stroke centers located in urban, suburban, and rural hospitals with a diverse population. All patients were treated for minor stroke or TIA between 2018 and 2021, and none were taking blood thinning medications before the stroke or TIA. Participants had an average age of 67 years; 42% were aged 70 years or older; 48% were women; and 37% were Black and 60% were White.

According to the study, DAPT was underutilized across all hospitals reviewed and were prescribed to just 40% of patients overall. Men were more likely than women (43% vs 37%, respectively) to be prescribed DAPT, although the percentage of patients receiving DAPT did not differ significantly by race, age, or whether the patient was treated at a stroke center that delivers specialized stroke care.

“There are an increasing number of options available to prevent and reduce the risk of a recurrent stroke, including high blood pressure medications, statins to control cholesterol, and dual blood thinners,” Solomonow said in the press release. “Patients and their family members should inquire about the use of DAPT after a stroke or TIA to consider if DAPT may be beneficial.”

Solomonow also noted that the study analyzed data from a single health-system, so the findings need to be confirmed in other settings. Notably, the gender gap seen in the study could not be explained by differences in insurance coverage or in anticipated adverse effects of the medications.

“The gender gap was not entirely surprising because there is extensive literature indicating that women with cardiovascular disease tend to be undertreated,” Solomonow said. “For example, some studies show that women with heart disease or stroke are not prescribed statins as frequently as men. In addition, women with atrial fibrillation receiving ablation less often than men. Further research is needed to examine whether women are less likely to receive other proven therapies, such as statins for stroke prevention and anti-coagulation for atrial fibrillation.”

REFERENCE

Dual blood thinners under prescribed after minor or warning stroke, especially in women. News release. American Heart Association; February 2, 2023. Accessed February 7, 2023. https://newsroom.heart.org/news/dual-blood-thinners-under-prescribed-after-minor-or-warning-stroke-especially-in-women?preview=6fa7