Science & technology

Study: Amphetamines Double Stroke Risk

Do amphetamines directly cause strokes or do lifestyle factors among users explain the risk?

Published MAR 9

Story

Above: People participated in the 2025 Marijuana March in Sao Paulo, Brazil, on June 14, 2025. Image credit: Faga Almeida/Universal Images Group/Getty Images

The Facts

A University of Cambridge study analyzing data from more than 100 million people found that amphetamine use was associated with a 122% higher stroke risk and cocaine use with a 96% higher risk compared to non-users, while cannabis use increased stroke risk by 37%.
Guardian
University of Cambridge
Among adults under age 55, amphetamine use was linked to a nearly threefold increase in stroke risk at 174%, cocaine use showed a 97% increase, and cannabis use was associated with a 14% increase in stroke risk compared to non-users.
The Independent
Men's Health
Researchers suggest recreational drugs may increase stroke risk through multiple mechanisms, including sudden blood pressure spikes, blood vessel constriction and spasm, heart rhythm problems, increased blood clotting, particularly with cannabis, and inflammation.
INKL
US News & World Report
The study used Mendelian randomization analysis, which examines genetic variants, to provide evidence suggesting a causal link between drug use and stroke rather than mere correlation, particularly for cocaine and cannabis use disorders.
Female First
University of Cambridge
Stroke is the third leading cause of death and disability worldwide, causing more than 7 million deaths annually and affecting approximately 100,000 people each year in the U.K., with an estimated nine out of 10 strokes being preventable.
The Independent
INKL
In 2024, approximately 2.9 million adults aged 16 to 59 in England and Wales reported using a legal or illegal recreational drug in the past year, representing about 8.8% of that age group, according to available data.
Female First
University of Cambridge

Sources Split

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The Spin

Narrative A

Amphetamines more than double stroke risk, with users under 55 facing a nearly threefold increase. The biological mechanisms are clear — sudden blood pressure spikes, vessel spasms, heart rhythm disruptions and increased clotting all directly cause strokes. This comprehensive analysis of over 100 million people provides compelling causal evidence that demands immediate public health action.

University of Cambridge

Female First

Men's Health

Narrative B

Recreational drug use correlates with higher stroke rates, but lifestyle factors among users likely explain much of the risk. Drug users often have poorer general health, worse diets and less exercise. The observational studies cannot prove causation, and focusing solely on drug prohibition ignores the broader preventable lifestyle choices that account for nine out of 10 strokes.

Guardian

The Independent

US News & World Report