A potential link between cannabis use and acute ischemic stroke (AIS), or a stroke resulting from loss of oxygen to the brain, has been a contentious topic for a while. Let’s discuss a few studies to get a better idea of the issue.
Possible Cause for Concern
Since cannabis can trigger certain cardiovascular and cerebrovascular reactions, such as increased heart rate and even tachycardia, there is certainly rationale to support a link.[1] It’s possible that, with certain predisposing factors, cannabis can be a catalyst for the perfect storm that culminates in something as serious as AIS. But what does the research say?
Studies Establishing a Connection
A study published in the Journal of the Neurological Sciences scoured the Nationwide Inpatient Sample, the largest database of US inpatient stays, to evaluate data from patients between 15 and 54 years old with a primary diagnosis of acute AIS from 2004 to 2011. [2]
They reported that “overall, the incidence of AIS was significantly greater among marijuana users compared to non-users,” with the greatest difference found in the 25-34-year-old group. Specifically, recreational cannabis use increased the risk of AIS hospitalization by 17% as an independent factor.[2]
Other studies have focused on ischemic stroke (IS), rather than AIS. A review of 59 case reports of cannabis-related strokes, 83% of which were IS, revealed two telling correlations.[3] First, IS was more prevalent among young males with chronic cannabis use than occasional users; these patients also happened to consume tobacco and alcohol before experiencing a stroke. Furthermore, the study established a temporal link between IS and cannabis use – the stroke took place within 30-60 minutes of cannabis consumption or even during use.
And this temporal link has been reported in other studies as well. One small study of 17 patients with IS not only confirmed this temporal link but also revealed that re-exposure to cannabis was associated with recurrence of symptoms.[4]. In yet another study of 71 heavy cannabis users with IS, the same 30-minute time frame surfaced again in 76.5% of cases.[5]
Conflicted Findings
Using the institutional patient cohort explorer, a study, which was the first to assess cannabis use with a urine toxicology test at admission, evaluated 9,350 patients with AIS. Researchers found that 18% had a positive urine cannabis test.[6]
“Consistent with some studies, this study shows that recent cannabis use is not an independent risk factor for ischemic stroke. Further studies utilizing urine toxicology tests with a larger sample size should be done,” the authors concluded.
The Bottom Line
There does seem to be a possible association between cannabis use and IS, which perhaps starts to become obscure as “acute” comes into the equation. We need additional studies to better understand this link and to determine if the temporal association does indeed hold.
It’s important to note that both cannabis and cannabidiol (CBD) can interact with some heart medications due a shared pathway that is responsible for breaking down these chemicals in the body. As always, be sure to talk to your doctor if you are currently using cannabis or CBD or plan to use cannabinoids to be certain there are no interactions with your medications.
Image Credits: https://www.npr.org/sections/health-shots/2016/09/13/492814117/as-more-states-consider-legalizing-questions-about-pot-and-the-brain
References
- Fischer, B.A., et al., “Cardiovascular Complications Induced by Cannabis Smoking: A Case Report and Review of the Literature”, Emerg Med J, vol.22, no.9, pg. 679-680.
- Rumalla, K., et al., “Recreational Marijuana Use and Acute Ischemic Stroke: A Population-based Analysis of Hospitalized Patients in the United States”, J Neural Sci,15, no.364, 2016, pg. 191-196.
- Wolff, V., et al., “Cannabis-related Stroke: Myth or Reality?” Stroke. vol.44, 2013, 558-563.
- Singh, N.N., et al., “Cannabis-related Stroke: Case Series and Review of Literature”, J Stroke Cerebrovasc Dis, vol.21, 2012, pg. 555-560.
- Desbois, A.C. & Cacoub, P. “Cannabis-Associated Arterial Disease.” Ann Vasc Surg, vol.27, no.7, 2013, pg. 996-1005.
- San Luis, C., et al., “Association Between Recent Cannabis Use and Acute Ischemic Stroke”, Neurology, vol.92, no.15, 2019.
