The association between marijuana use and C-reactive protein: A longitudinal analysis


Ferguson, Erin & Ennis, Nicole (2018). The association between marijuana use and C-reactive protein: A longitudinal analysis. 2018 Add Health Users Conference. Bethesda, MD.


Introduction: Systemic inflammation is implicated in the development and progression of chronic diseases such as cancers, cardiovascular disease, and diabetes. C-reactive protein is a reliable measure of inflammation in the body. Research suggests that marijuana use, specifically cannabinoid-2 receptor activation, facilitates an anti-inflammatory response. However, few studies have investigated how marijuana use impacts physical measures of inflammation, such as C-reactive protein (CRP), and results are inconclusive. Therefore, the present study aimed to characterize the longitudinal relationship between smoking marijuana and serum C-reactive protein levels in adulthood. Methods: The National Longitudinal Study of Adolescent to Adult Health was utilized, which includes a nationally representative sample of adolescents in grades 7-12 in the 1994-5 school year (Wave I) and five consequent follow-up interviews. This sample is comprised of respondents interviewed at Wave III and Wave IV (N=11,006). Marijuana use during the past 30 days was assessed in Wave III and dichotomized as non-users (0) and users (1). CRP was dichotomized with a cutpoint of 5 mg/L, as prior literature indicates a CRP reading of above 5 mg/L suggests elevated inflammation and increased risk for disease. Weighted logistic regression analyses for complex samples in SPSS were used to examine the association between marijuana use at Wave III and C-reactive protein levels at Wave IV. Results: Approximately 76.5 % and 23.5% of the sample were non-marijuana users and marijuana users respectively. Results indicate that marijuana users had a significantly greater odds of having lower CRP levels (<5 mg/L) in adulthood (AOR=1.18, 95% CI=1.01-1.38) when controlling for exercise, cigarette and alcohol use, and relevant sociodemographic characteristics in Wave 3. Conclusions: Consistent with recent literature, these findings suggest an anti-inflammatory effect of marijuana use. Marijuana use in early adulthood was associated with lower CRP levels in later adulthood, even after controlling for relevant covariates. These results are a first step in examining the effect of marijuana use on systemic inflammation.

Reference Type

Conference proceeding

Book Title

2018 Add Health Users Conference


Ferguson, Erin
Ennis, Nicole

Year Published


City of Publication

Bethesda, MD

Reference ID