A new analysis published in the journal Hypertension found no association between cumulative, long-term marijuana use and the risk of developing hypertension, even after 35 years of follow-up.

The work draws on the CARDIA cohort (Coronary Artery Risk Development in Young Adults) and was conducted by a team from UC San Diego, Wake Forest University School of Medicine, the University of Bern and affiliated Swiss institutions, Northwestern University Feinberg School of Medicine, the National Heart, Lung, and Blood Institute, and others.

Researchers evaluated 4,328 Black and White adults who were 18 to 30 at enrollment (1985–1986) and free of hypertension at baseline. Marijuana exposure was quantified as “cannabis-years,” where one cannabis-year equals 365 days of use. Across 88,292 person-years, there were 2,478 incident hypertension cases—an incidence rate of 28.1 per 1,000 person-years. After accounting for time-varying confounders with marginal structural models and Cox regression, cumulative marijuana use was not significantly associated with incident hypertension (adjusted hazard ratio ≈1.0; primary model 0.99 with a 95% CI of 0.97–1.00; P=0.18). Results were unchanged after additional adjustments that included alcohol, cigarette smoking, BMI, physical activity, diabetes, dyslipidemia and psychiatric medication use.

Sensitivity work told the same story. Analyses stratified by sex, race, alcohol use and cigarette smoking found no meaningful effect modification. A secondary exposure measure—days used in the past month—also was not significantly linked to incident hypertension in fully adjusted models (adjusted HR 1.03; P=0.06). Restricted cubic spline analyses suggested only a modest uptick in risk at the very highest lifetime exposures, but estimates were imprecise because relatively few participants reported such heavy use. Overall, cumulative exposure in this cohort remained low for most participants across visits.

The authors note that their findings contrast with concerns drawn from acute studies showing marijuana can transiently elevate heart rate and alter vascular tone. They argue that, at the population level and over decades, repeated use did not translate into a higher rate of diagnosable hypertension. That conclusion aligns with several prospective analyses from CARDIA and other cohorts that have not found adverse long-term associations between marijuana use and key cardiovascular risk factors.

The results suggest long-term marijuana use, at levels typical in this large community cohort, does not meaningfully contribute to hypertension risk. Researchers conclude by stating:

In a cohort of Black and White young adults with 35 years of follow-up, no association was found between cumulative lifetime use of cannabis and risk of incident hypertension. This finding was robust to restricted cubic spline analyses, analyses stratified by sex, race, alcohol use and tobacco cigarette smoking, and an additional measure of exposure (days of use in the past month).