Cannabis itself is harmful to cardiovascular health and increases the chance of early death regardless of related factors such as smoking tobacco, new research reveals.

Data taken from more than 1,000 US hospitals found that people who used the drug had a 26 per cent higher chance of suffering a stroke than those who did not, and a 10 per cent higher chance of having a heart attack.

The findings held true after taking into account unhealthy factors known to affect many cannabis smokers, such as obesity, alcohol misuse and smoking.