Le cannabis, le tabac et le changement d’adiposité chez les jeunes hommes et femmes : une étude longitudinale 2005-2012
Background: Animal studies suggest that the endocannabinoid system is a regulator of energy homeostasis, whose effects are modified by sex and nicotine. Two studies in humans have examined the association between cannabis use and change in adiposity, and obtained conflicting results. This thesis aimed to determine if the association between cannabis use and change in adiposity is modified by cigarette smoking in young adults. Methods: Data were available for 271 males and 319 females participating in the Nicotine Dependence In Teens study, a prospective cohort investigation (1999-2013). Body mass index (BMI) and waist circumference (WC) were measured at ages 17 and 25 years. Self-report data on past-year cannabis use and past three-month cigarette smoking were collected at age 21 years. Modification of the association between cannabis use and change in adiposity by cigarette smoking was tested separately in each sex, in polynomial linear regression models controlling for physical activity and sedentary behavior in both sexes, and alcohol use in males only. Results: In males only, the interaction between cannabis use and cigarette smoking was statistically significant in both the model for change in BMI (p=0.004) and the model for change in WC (p=0.043). Cannabis use was associated with change in adiposity in a U-shaped form in females and in non smoking males, and in an inverted U-shaped association in males who smoked more than 10 cigarettes per day. Conclusion: Smoking cigarettes appears to attenuate the association between cannabis use and change in adiposity in young men, but not in young women.
Cannabis Cigarette Endocannabinoid system Cannabis Cigarette Obesity Effect modification