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

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).

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.

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.

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.

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.