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Cambridge study links cannabis, cocaine, and amphetamines to elevated stroke risk

A meta-analysis of data from more than 100 million individuals indicates that recreational use of several substances significantly raises the likelihood of stroke.

Updated Aug 24, 2026 · 00:17 UTC1 reports

The short version

  • A University of Cambridge meta-analysis covering more than 100 million people found significant increases in stroke risk tied to cocaine, amphetamine, and cannabis use.
  • Amphetamine use was linked to a 122% increase in stroke risk, cocaine to a 96% increase, and cannabis to a 37% increase, with younger users facing disproportionate risks from amphetamines.
  • Mendelian randomization analysis suggests potential causal connections between certain drug use disorders and specific stroke subtypes, whereas opioid use showed no statistically significant link.
  • Researchers emphasize the findings can inform public health interventions and guide future cardiovascular research.

Key facts

  • A meta-analysis published in the International Journal of Stroke analyzed data from over 100 million participants to assess recreational drug use and stroke risk.[ScienceDaily]
  • Researchers found amphetamine use was linked to a 122% higher stroke risk, cocaine use to a 96% increase, and cannabis use to a 37% increase.[ScienceDaily]
  • Among adults under 55, amphetamine use was associated with a 174% higher risk of stroke, cocaine with a 97% increase, and cannabis with a 14% increase.[ScienceDaily]
  • Opioid use was not found to have a statistically significant association with stroke risk in the analysis.[ScienceDaily]
  • Mendelian randomization supported potential causal links between cocaine use disorders and brain hemorrhages or cardioembolic strokes, and between cannabis use disorders and large artery strokes.[ScienceDaily]
  • The research was funded by the British Heart Foundation and the National Institute for Health and Care Research Cambridge Biomedical Research Centre.[ScienceDaily]

What remains uncertain

  • The study could not perform Mendelian randomization analysis on amphetamine use because sufficiently large genetic datasets were unavailable.[ScienceDaily]

Sources