Adherence to gender-typical behavior and high frequency substance use from adolescence into young adulthood.

Substance use is prevalent among adolescents in the U.S., especially males. Understanding the cross-sectional and longitudinal associations between gender norms and substance use is necessary to tailor substance use prevention messages and efforts appropriately. This study investigates the relationship between adherence to gender-typical behavior (AGB) and substance use from adolescence into young adulthood. Participants in the National Longitudinal Study of Adolescent to Adult Health completed self-report measures on the frequency of binge drinking, cigarette smoking and marijuana use as well as various behaviors and emotional states that captured the latent construct of AGB. Sex-stratified logistic regression models revealed cross-sectional and longitudinal relationships between AGB and high frequency substance use. For example, an adolescent male who is more gender-adherent, compared to less adherent males, has 75% higher odds of high frequency binge drinking in adolescence and 22% higher odds of high frequency binge drinking in young adulthood. Sex-stratified multinomial logistic regression models also revealed cross-sectional and longitudinal relationships between AGB and patterns of use. For example, a more gender-adherent adolescent male, compared to one who is less adherent, is 256% more likely to use all three substances in adolescence and 66% more likely to use all three in young adulthood. Cross-sectional and longitudinal results for females indicate greater gender-adherence is associated with lower odds of high frequency substance use. These findings indicate adherence to gender norms may influence substance use behaviors across the developmental trajectory, and inform strategies for prevention efforts.

Testing Longitudinal Relationships Between Binge Drinking, Marijuana Use, and Depressive Symptoms and Moderation by Sex.

PURPOSE: Both substance use and depression are common in adolescence and often comorbid. Past research has produced conflicting results on whether there is a temporal relationship, and if so, in which direction it operates and how it may vary by sex. We examined the longitudinal associations between substance use frequency and depressive symptoms from adolescence into young adulthood and whether the associations were moderated by sex. METHODS: With data from Waves I, III, and IV of the National Longitudinal Study of Adolescent to Adult Health (n = 9,816), we used growth curve models to test if depressive symptoms predicted marijuana use or binge drinking frequency (Self-Medication Model) or if substance use frequency predicted depressive symptoms (Stress Model). Moderation by sex and age was tested for both potential pathways. RESULTS: Increases in adolescent depressive symptoms, compared to no symptoms, were associated with a steeper predicted increase in marijuana use frequency from adolescence to young adulthood. Increases in persistent binge drinking or marijuana use frequency had concurrent positive associations with depressive symptoms from adolescence to young adulthood, and these associations were significantly stronger for females compared to males. CONCLUSIONS: The results not only support the Self-Medication Model for marijuana use but also provide modest support for the Stress Model, that substance use is associated with depressive symptoms, especially for females.

Directions of the relationship between substance use and depressive symptoms from adolescence to young adulthood.

PURPOSE: Both substance use and depression are common in adolescence and often comorbid. Past research has produced conflicting results on whether there is a temporal relationship and if so, in which direction it operates and how it may vary by sex. The purpose of this paper is to explore the longitudinal, potentially bidirectional, relationships between high-frequency substance use and depressive symptoms from adolescence into young adulthood for males and females. METHODS: Using data from the National Longitudinal Study of Adolescent to Adult Health we investigated longitudinal associations between high frequency substance use (alcohol, cigarettes, and marijuana) and depressive symptoms. The linear mixed effects models were stratified by sex and used a lagged measure of the dependent variable to test temporal relationships. A random intercept was used for respondent ID. RESULTS: Increases in depressive symptoms were significantly associated with a later increase of about a half day in marijuana use frequency for males and nearly a two day increase in smoking frequency for females. Conversely, increases in smoking frequency were significantly associated with approximately a 0.6-point increase for females and 0.4-point increase for males in depressive symptoms at a later wave. CONCLUSIONS: Results indicate a bidirectional relationship between smoking and depressive symptoms for females. For males, there was evidence supporting self-medication with marijuana and for smoking being associated with later increases in depressive symptoms. Results inform how substance use and depression screening, prevention and treatment efforts should be paired and targeted for males and females.

Diurnal variation in nicotine sensitivity in mice: role of genetic background and melatonin.

Despite the evidence that there is a daily rhythm in smoking behavior and that the effects of drugs of abuse exhibit diurnal variations, very few studies have explored the extent to which sensitivity to the effects of nicotine vary over the course of the day. In the studies described in this report, the melatonin proficient mouse strain C3H/Ibg and the melatonin deficient mouse strains C57BL/6J and DBA/2J were assessed for diurnal variations in sensitivity to the effects of nicotine. Results indicated that there is significant variation in sensitivity to both activity and body temperature depressant effects of nicotine in the melatonin proficient C3H/Ibg strain with maximal sensitivity occurring during the latter third of the light period of the light cycle and minimal sensitivity taking place during the last third of the dark phase of the light cycle. The melatonin deficient strains did not exhibit diurnal differences in sensitivity to the effects of nicotine suggesting a potential role for melatonin in modulating the effects of nicotine. Experiments with knockout mice lacking both the Mtnr1a and Mtnr1b melatonin receptors confirmed that the reduced sensitivity observed during the dark phase is melatonin dependent. Diurnal variation in nicotinic receptor expression also was measured in cortex, hippocampus, hypothalamus and striatum using [(125)I]-α-bungarotoxin and [(125)I]-epibatidine. [(125)I]-α-bungarotoxin binding in hypothalamus of C3H mice exhibited a diurnal pattern with maximal binding observed in the latter third of the light portion of the light cycle. No other significant differences in binding were detected.