Abstract P262: Self-Reported Marijuana Use and Abdominal Adiposity Measured by Computed Tomography: The Coronary Artery Risk Development in Young Adults Study
Introduction: Animal models suggest that cannabis has anti-inflammatory properties that improve cardiovascular and metabolic health outcomes, however, in humans the results are sparse and equivocal. One potential mechanism that may link marijuana use to increased disease risk may be an association with abdominal adipose tissue volume and liver fat infiltration. The purpose of this study was to quantify the association between lifetime marijuana use and visceral adipose tissue (VAT), total abdominal adipose tissue (TAAT) and liver steatosis.
Methods: We examined the cross-sectional association between self-reported marijuana use and computed tomography (CT) measures of VAT, TAAT, and liver attenuation (LA) in CARDIA participants at exam year 25, including 2327 men and women 18-30 years of age at enrollment (1985-1986). Lifetime frequency of marijuana use was determined from responses given to self-administered questionnaires (never, 1-9, 10-99, and ≥100 times; respectively 21%, 35%, 21%, and 23% of the analytic sample). Non-contrast CT was used to quantify abdominal adipose tissues and LA. CT measures were performed centrally, by experienced analysts, using standard methods on a dedicated workstation blinded to other participant information. The volume (mL) of abdominal fat (threshold -35 to -190 Hounsfield Units, HU) were made using a 10 mm thick cross-section, composed of thinner 1 mm slices, center at the level lumbar disk between the 4th and 5th (L4-L5) vertebra . LA was measured by averaging 9 regions of interest in the right lobe of the liver. Multivariable linear regression estimated adjusted means for VAT, TAAT, and LA according to marijuana use category, before and after adjustment for age, sex, race, education, study center, smoking status, alcohol consumption and physical activity.
Results: Older age, male sex, white race, current smoking, greater waist circumference, alcohol consumption, and physical activity were all associated with greater lifetime use of marijuana, while greater education was associated with lower lifetime use. In unadjusted analyses, individuals who reported lifetime use of marijuana ≥100 times had significantly higher mean volume of VAT compared to never users (143.0 ml vs. 132.7 ml; p-value=0.02), and significantly lower TAAT (480.2 ml vs. 532.2 ml; p-value <0.001) and LA (53.7 HU vs. 56.8 HU; p-value <0.001). In multivariable models, no frequency of marijuana use was associated with VAT, TAAT, or LA. Adjustment for age, alcohol consumption, and physical activity were largely responsible for the noted attenuations.
Conclusion: After accounting for potential confounders, marijuana use in young adulthood was not associated with presence of visceral adiposity, total abdominal adiposity, or liver steatosis in middle adulthood.
Author Disclosures: M.P. Bancks: None. J.J. Carr: None. D.C. Goff: None. C.I. Kiefe: None. J.S. Rana: None. C.M. Shay: None. S. Sidney: None. J.G. Terry: None. P.J. Schreiner: None.
- © 2015 by American Heart Association, Inc.