Abstract MP44: Lifetime Marijuana Use is Not Associated with Incident Cardiovascular Disease in Middle-Age: The Coronary Artery Risk Development in Young Adults (CARDIA) Study
Background: Marijuana is the most frequently used illicit drug in the US. Its use is expected to rise given recent state policies that relax criminalization and permit medicinal use. Although several mechanisms exist by which marijuana might contribute to chronic cardiovascular conditions, few data are available. We sought to determine the association of lifetime marijuana use with the development of incident CHD and CVD.
Methods: Participants were 5,114 white and black adults aged 18-30 years in 1985-86 from the multicenter, community-based CARDIA Study who have been followed for over 25 years. We estimated cumulative years of exposure in “marijuana-years,” with one marijuana-year equal to 365 days of marijuana use using repeated assessments every 2-5 years. Incident CHD included fatal or nonfatal myocardial infarction, angina, or CHD death. Incident CVD included CHD, stroke, hospitalized heart failure, and intervention for peripheral arterial disease. Cox proportional hazards models were used to estimate hazard ratios and 95% confidence intervals. Lifetime marijuana use and all time-varying covariates were entered as time-dependent variables.
Results: Approximately 16% of the cohort were lifetime never users of marijuana, while 35%, 22%, 14%, and 13% reported lifetime use of <0.5, 0.5-<2, 2-<5, and ≥5 marijuana-years, respectively. During a median of 26.9 years of follow-up (132,120 person-years), there were 104 and 216 cases of CHD and CVD, respectively. Compared to never use, categories of lifetime marijuana use showed no evidence for a higher or lower risk for CHD or CVD, regardless of the level of multivariable adjustment (Table). Findings did not vary significantly by age, sex, race, family history, 10-year risk of CVD, or use of other illicit drugs (p-interaction >0.3, for all).
Conclusions: In this long-term follow-up study of young adults at baseline, lifetime use of marijuana at these levels was not associated with incident CHD or CVD in middle-age.
Author Disclosures: J.P. Reis: None. R. Auer: None. D. Goff: None. C. Lewis: None. M. Pletcher: None. J. Rana: None. S. Sidney: None.
- © 2016 by American Heart Association, Inc.