Thirty-five years of follow-up found no association between cumulative cannabis use and developing hypertension | Research

The takeaway

In the CARDIA study following over 4,300 adults for 35 years, cumulative lifetime cannabis use was not associated with developing hypertension, a finding that held across sensitivity analyses stratified by sex, race, and other substance use.

Cardiologists, epidemiologists, and public health researchers studying long-term cardiovascular effects of cannabis.

HR 0.99 over 35 years

What the researchers found

Cannabis-years were not significantly associated with incident hypertension (adjusted HR 0.99, 95% CI 0.97-1.00, p=0.18) over 35 years. This null finding was robust to restricted cubic spline analyses, stratification by sex, race, alcohol use, and tobacco smoking, and an alternative exposure measure (days of use in the past month).

Why it matters

Previous evidence on cannabis and hypertension has been inconsistent. This study provides the longest follow-up to date with sophisticated methods to handle time-dependent confounding, and finds no relationship.

The numbers in context

N = 4,328 at baseline, 2,810 (64.9%) at year 35. Median cannabis-years remained low across visits: 0.0 at baseline, 0.2 by year 35. There were 2,478 incident hypertension cases over 88,292 person-years (28.1 per 1,000 person-years). Adjusted HR: 0.99 (0.97-1.00).

How the study worked

Marginal structural models with inverse probability weighting in the CARDIA study, following 4,328 participants free of cardiovascular disease at baseline for 35 years. Cannabis-years measured cumulative lifetime use. Cox proportional hazards regression estimated hazard ratios. Sensitivity analyses included spline models and stratification.

What this study cannot tell us

Median cannabis use was low across the cohort, limiting the ability to assess effects of heavy, sustained use. Self-reported cannabis use may underestimate exposure. Marginal structural models address but do not eliminate time-dependent confounding.

How to read the evidence

Long-duration prospective cohort with sophisticated causal inference methods (marginal structural models) and extensive sensitivity analyses, though limited by low median cannabis exposure.

When this study was published

2025 publication with 35 years of follow-up

The bigger picture

This is among the most rigorous examinations of cannabis and hypertension to date, leveraging a biracial longitudinal cohort with decades of follow-up. The null finding is informative given the cardiovascular concerns that surround cannabis use.

Questions still open

Would higher levels of cannabis use show an association? Do acute cardiovascular effects of cannabis translate into long-term cardiovascular risk through mechanisms other than hypertension?

Common questions

Does cannabis use cause high blood pressure?

This 35-year study found no association between cumulative lifetime cannabis use and developing hypertension. The finding was consistent across analyses stratified by sex, race, and other substance use.

Why is this study particularly informative?

It has the longest follow-up to date (35 years), uses advanced statistical methods to address time-dependent confounding, and includes a biracial cohort. However, most participants had relatively low cannabis use, so effects of heavy use remain unclear.

Read the original research

Lifetime Cannabis Use and Incident Hypertension: The Coronary Artery Risk Development in Young Adults (CARDIA) Study.

Hypertension (Dallas, Tex. : 1979), 82(10), 1641-1652

View on PubMed ↗Publisher’s paper ↗

Citation

Corroon, Jamie; Bradley, Ryan; Grant, Igor; Bancks, Michael P; Jakob, Julian; Auer, Reto; Reis, Jared P; Allen, Norrina; Yeh, Kuan-Hung; Allison, Matthew A. (2025). Lifetime Cannabis Use and Incident Hypertension: The Coronary Artery Risk Development in Young Adults (CARDIA) Study.. Hypertension (Dallas, Tex. : 1979), 82(10), 1641-1652. https://doi.org/10.1161/HYPERTENSIONAHA.125.25005