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RJ Balde

Researchers found that patients with aneurysmal subarachnoid hemorrhage, a form of bleeding stroke, who had recently used cannabis had an increased likelihood to have delayed cerebral ischemia than those who had not.

“We’re all vulnerable to a bleeding stroke or a ruptured aneurysm; however, if you’re a routine marijuana user, you may be predisposed to a worse outcome from a stroke after the rupture of that aneurysm,” said Michael T. Lawton, MD, president and CEO of Barrow Neurological Institute in Phoenix, Arizona, in a press statement.

Researchers with Barrow Neurological Institute examined 1,014 patients between August 2007 and July 2019 who had aneurysmal subarachnoid hemorrhage and found that 4.5 percent of them screened positive for cannabis during normal urine toxicology testing. Of cannabis users, the average age was 47 years, with 41 percent being women. Of non-cannabis-users, the average age was 56 years, with 71 percent being women. Within the cohort, 36.2 percent of them suffered delayed cerebral ischemia, 50.2 percent had a reduced functional result (a modified Rankin Scale score greater than 2), and 13.5 percent perished.

Delayed cerebral ischemia was more likely in cannabis users than in non-cannabis-users, according to Lawton and researchers, although there was no link among delayed cerebral ischemia and screening positive for cocaine, methamphetamine, or tobacco. As per the research, individuals who screened positive for cannabis had more radiographic vasospasm than those who screened negative for cannabis, and in those with radiographic vasospasm, 50 percent of cannabis users experienced delayed cerebral ischemia versus 39 percent of non-cannabis-users. Cannabis consumption was linked to delayed cerebral ischemia in the patient group in a propensity score-adjusted assessment.

“When people come in with ruptured aneurysms, and they have a history of cannabis use or are positive on a toxicology screen, it should raise a red flag to the treating team that they are at higher risk of vasospasm and ischemic complication,” said Lawton. “Of all the substances detected in the toxicology screen, only cannabis raised the risk of delayed cerebral ischemia. Cocaine and meth are hypertensive drugs, so they are likely related to the actual rupture but not expected to have an impact on vasospasm.”

Feras Akbik, MD, PhD, and Ofer Sadan, MD, PhD, assistant professors of neurology and neurosurgery at Emory University School of Medicine in Atlanta, Georgia, stated in a pertaining editorial:

“Ultimately, given the prior mixed results regarding the association of marijuana with cardiovascular complications, ischemic stroke or hemorrhagic stroke, it remains an open question whether cannabis precipitates cerebral ischemia via cerebral vasospasm and delayed cerebral ischemia. Future studies should attempt to better quantify the cannabis exposure in terms of chronicity, dose and temporal relationship between the cannabis use and the aneurysm rupture event, in order to better understand whether indeed marijuana can precipitate cerebral ischemia.”