A brand-new research study that utilized admission urine toxicology tests to establish substance abuse discovered no independent association in between current marijuana usage and the occurrence of severe ischemic stroke.
“Previous research studies have actually revealed conflicting information on marijuana usage and stroke. Our research study is an advance because we had rather a big population and we had an unbiased step of cannabis usage with the urine screen, whereas some previous research studies have actually simply depended on asking the client about cannabis usage,” senior author Shreyas Gangadhara, MD, University of Mississippi Medical Center, Jackson, informed Medscape Medical News.
This most current research study was released online in Neurology on June 3.
The scientists, led by Carmela V. San Luis, MD, likewise from the University of Mississippi Medical Center, note that the concern regarding whether marijuana usage is connected to severe ischemic stroke was raised after a number of case reports recommended such a connection. A couple of population-based analyses of hospitalized clients have actually likewise revealed a favorable association.
A previous research study revealed no association in between marijuana usage and stroke after managing for diabetes mellitus, high blood pressure, alcohol usage, migraine, smoking, and age, however that research study depended on clients’ reports for cannabis usage, and no unbiased tests were carried out. There is likewise proof of neuroprotectant results of cannabidiol in the main nerve system, and animal research studies have actually recommended it might be protective versus ischemic stroke, so the proof is contrasting.
“We performed the existing research study due to the fact that we have actually seen in medical practice lots of more youthful clients with an ischemic stroke however no standard stroke threat elements who had a favorable urine test for marijuana. As there is no agreement on this in the literature up until now, we wished to take a look at this even more,” Gangadhara stated.
For the retrospective observational research study, the scientists evaluated the medical records database for all clients aged 18 years and older who were confessed to the University of Mississippi Medical Center from 2015 to 2017 and who went through urine toxicology screening on admission.
Owing to problem in distinguishing real short-term ischemic attack (TIA) from mimics, such as migraine with aura, clients who were detected with TIAs were omitted. Those with intracranial hemorrhage whose outcomes of urine drug screening were favorable for amphetamine or drug were likewise omitted.
Outcomes revealed that of 9350 clients who went through urine drug screening throughout admission, 18% had a favorable outcome on urine marijuana screening.
Unadjusted threat ratio revealed a 50% decline in threat for severe ischemic stroke amongst marijuana users (threat ratio, 0.50; 95% self-confidence period [CI], 0.42 – 0.60), however this impact was lost after changing for possible confounders, consisting of age, race, ethnic background, sickle cell illness, dyslipidemia, high blood pressure, weight problems, diabetes mellitus, smoking, atrial fibrillation, and other heart conditions (chances ratio, 1.04; 95% CI, 0.77 – 1.39).
The authors keep in mind that this outcome is not in line with previous research studies that consisted of individuals with polysubstance usage however not individuals who just utilized marijuana, which might discuss the distinction.
They likewise mention that a previous research study discovered an association in between reported heavy cannabis usage and history of stroke, however there was no association for those who utilized cannabis less than when a week. The existing research study did not assess for dosage, chronicity, and frequency of marijuana direct exposure.
The scientists keep in mind that cannabinoids have both damaging and protective results in the nerve systems, which might represent the conflicting lead to different research studies and the general neutral results discovered in the existing research study. Nevertheless, the conflicting outcomes might likewise be because of little sample size.
“I would not state that this is completion of the story. We do not have all the responses,” Gangadhara stated. “This was a retrospective research study, and we could not measure using cannabis. We could not take a look at how often or just how much was utilized. It was more of a yes-or-no concern.”
They likewise report that urine drug screening does not evaluate for artificial cannabinoids; for that reason, artificial marijuana usage was not examined.
The scientists conclude: “More potential research studies need to be finished with a bigger sample size and checking out dose-related results.”
Commenting for Medscape Medical News, Tarang Parekh, MBBS, a health policy scientist at George Mason University, Fairfax, Virginia, stated the research study is necessary thinking about current legalization and decriminalization of marijuana usage in the United States. “With increasing appeal, extensive information on any associated link in between cannabis and stroke stays important,” he commented.
Parekh, who has actually likewise been associated with research study in this location, noted strengths of the existing analysis as sample size, usage of medical records information, and control for possible threat elements and confounders. However he explains that in this research study, 3 control variables that are currently understood to be related to stroke ― smoking cigarettes, weight problems, and diabetes ― were discovered to be nonsignificant.
“The essential issue with that is we cannot translate the findings of this research study that there is no association in between any of these 3 threat elements and ischemic stroke. The exact same is gotten current marijuana usage,” he stated.
Parekh keeps that the unadjusted threat ratio suggesting a 50% decline in threat need to be overlooked due to the fact that of the “plain distinction” in between marijuana users and nonusers with regard to demographics and threat elements. Users were much more youthful, and almost all comorbid conditions were less widespread amongst users than nonusers.
“As the authors recommended, it would deserve performing longitudinal research studies checking out the temporal relationship in between the period and dose-dependent relationship with stroke utilizing a bigger sample size. Till then, it would risky to overlook the health issue evidenced and raised by numerous case reports and research studies,” he concluded.
Neurology. Released online June 3, 2020. Abstract
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