A study involving more than 500 young adults found no significant overall differences in arterial stiffness between marijuana users and nonusers.
The study, published August 29 in Scientific Reports, examined 501 adults ages 18 to 34, including 222 men and 279 women. Researchers with the EVA-Adic study assessed marijuana use using the Alcohol, Smoking and Substance Involvement Screening Test.
Arterial stiffness refers to a loss of flexibility in the arteries and is considered an indicator of vascular health. Researchers evaluated participants using several measures, including pulse pressure, carotid-femoral and brachial-ankle pulse wave velocity, the cardio-ankle vascular index and the central augmentation index corrected to a heart rate of 75 beats per minute, known as CAIx75.
Across the group as a whole, researchers found no significant differences in the measured arterial stiffness parameters between marijuana users and nonusers. The same was true when participants were analyzed separately by sex. Logistic regression models also found no association between either past or recent marijuana use and the arterial stiffness measures.
One exception emerged after researchers adjusted for age and sex. Marijuana use was associated with a higher central augmentation index adjusted to a heart rate of 75 beats per minute (CAIx75), a measure of pressure-wave reflection in the arteries. The association remained after researchers further adjusted for lifestyle factors.
However, the researchers cautioned against interpreting the isolated result as evidence that marijuana causes arterial stiffening. “This isolated finding concerning CAIx75 may reflect a subtle functional or hemodynamic difference rather than established structural arterial stiffening,” they wrote, adding that unmeasured factors or chance could also explain the association.
The marijuana users in the study were younger on average, at about 24.8 years compared with 26.7 years among nonusers. The research was cross-sectional, meaning participants were evaluated at a single period in time and the study cannot establish cause and effect.
The findings contrast with some smaller previous studies that have reported increased arterial stiffness following marijuana use. The researchers concluded that, overall, “no significant differences in arterial stiffness parameters were found based on cannabis use”.
