Study on cumulative cannabis use and the link with intima-media thickness of the carotid artery
A team of researchers from the United States and Switzerland evaluated the association between cannabis exposure and carotid thickness in young people. Atherosclerosis is a major cardiovascular risk factor. Future cardiovascular disease is often indicated by atherosclerosis. This is the loss of elasticity of the arteries due to sclerosis, itself caused by the accumulation of fatty substances (mainly bad cholesterol known as LDL) in the inner lining (intima) of the arteries. According to the study CARDIA (Coronary Artery Risk Development in Young Adults), middle-aged subjects with a history of cannabis use do not have a higher risk of atherosclerosis (hardening of the arteries), according to longitudinal data published in theAmerican Journal of Medicine.
Heavy cannabis use is not associated with hardening of the arteries
The effects of cannabis on long-term cardiovascular health are still under-studied. This research evaluated a group of 5115 women and men and investigated the association between mid-life carotid intima-media thickness and lifetime exposure to marijuana (365 days of use) and smoking. (20 cigarettes / day for 365 days).
Researchers measured carotid intima-media thickness by ultrasound and defined an elevated carotid intima-media thickness at the 75th percentile threshold (k = P * n / 100) of all participants examined. Subsequently, they fitted logistic regression models stratified by tobacco exposure, adjusting for demographics, cardiovascular risk factors, and other drug exposures.
In the end, the data was complete for 3257 participants of which 2722 (84%) declared having already used marijuana and 374 (11%) were current users with 1539 (47%) who declared having ever smoked tobacco; 610 (19%) were current smokers.
Multivariate fitted models showed no association between cumulative marijuana exposure and high carotid intima-media thickness in never or never smokers. Cumulative exposure to tobacco was strongly associated with high carotid intima-media thickness.
No association between mean level of consumption and subclinical atherosclerosis
While cumulative tobacco use was strongly associated with high intima-media carotid thickness (odds ratio 1,88), exposure to marijuana was not (OR 0,87).
This study adds to the growing body of evidence that there may be no association between the average level of herb consumption in the population and subclinical atherosclerosis. The authors concluded:
"This study adds to the growing body of evidence that there may be no association between the average level of marijuana use in the population and subclinical atherosclerosis."
The results are in line with previous studies which indicate that neither current nor cumulative cannabis use is associated with atherosclerosis or other cardiovascular abnormalities in middle age.