Heavy pot smoking could raise risk of heart attack, stroke

Heavy, long-term pot smoking might raise the risk of developing a stroke or heart attack, a new study found.

Heavy, long-term pot smoking might raise the risk stroke or heart attack, a new study found.

Researchers at the National Institutes of Health Biomedical Research Centre in Baltimore studied whether heavy, chronic smoking of marijuana changed certain blood proteins associated with heart disease and stroke.

Eighteen participants who admitted to smoking an average of 138 joints per week over an average of six years were recruited. None had major psychiatric illnesses, high blood pressure, head injuries, were HIV-positive or had alcohol or drug dependencies.

Their blood samples were taken and measured against 24 non-drug-using volunteers.

A special protein chip that can identify blood proteins was used to analyze the blood samples.

Researchers found that apolipoprotein C-III was significantly increased in chronic marijuana smokers. Blood levels of the control participants were an average of 91.2 milligrams per 100 millilitres versus 122 milligrams per 100 millilitres for the pot smokers.

The protein, which transports triglycerides in the body, is known to slow their breakdown.

Triglyceride levels were also higher in the marijuana smokers.

Triglycerides are a type of fat that circulates in the blood. High levels of triglycerides can contribute to hardening of the arteries and an increased risk of heart attack.

The researchers believe this accumulation of apolipoprotein and triglycerides could explain why marijuana users are more likely to suffer heart attacks and strokes.

The study was published Tuesday online in the journal Molecular Psychiatry.