Cannabis and Stroke – Systematic Appraisal of Case Reports

Abstract

Background and Purpose

An increasing number of case reports link cannabis consumption to cerebrovascular events. Yet these case reports have not been scrutinized using criteria for causal inference.

Methods

All case reports on cannabis and cerebrovascular events were retrieved. Four causality criteria were addressed: temporality, adequacy of stroke work-up, effects of re-challenge, and concomitant risk factors that could account for the cerebrovascular event.

Results

There were 34 case reports on 64 patients. Most cases (81%) exhibited a temporal relationship between cannabis exposure and the index event. In 70%, the evaluation was sufficiently comprehensive to exclude other sources for stroke. About a quarter (22%) of patients had another stroke after subsequent re-exposure to cannabis. Finally, half of patients (50%) had concomitant stroke risk factors, most commonly tobacco (34%) and alcohol (11%) consumption.

Conclusion

Many case reports support a causal link between cannabis and cerebrovascular events. This accords well with epidemiological and mechanistic research on the cerebrovascular effects of cannabis.

  1. Daniel G. Hackam, MD, PhD, FRCPC

+Author Affiliations

  1. From the Division of Clinical Pharmacology, Department of Medicine, Western University, London, Ontario, Canada.

  1. Correspondence to Daniel G. Hackam, MD, PhD, FRCPC, 1400 Western Rd, London, Ontario, Canada N6G 2V2. E-mailĀ dhackamuwo.ca

Source: http://stroke.ahajournals.org/content/early/2015/02/19

Back to top of page

Powered by WordPress