Introduction

Studies suggest students who are substantially older than the average age for their grade engage in risky health behaviors, including substance use. However, most studies do not account for the distinct reasons why students are old for their grade (ie, grade retention vs delayed school entry) or for their pubertal stage. Thus, whether the association between age for grade and substance use is confounded by these factors is unknown. We sought to determine whether age, grade, or pubertal stage were associated with early substance use.

Methods

Cross-sectional Healthy Passages Wave I survey data from 5,147 fifth graders and their caregivers in Alabama, California, and Texas from 2004 through 2006 were analyzed in 2014. Logistic regressions examined whether older age for grade, grade retention, delayed school entry, or pubertal stage were associated with use of any substance, cigarettes, alcohol, or other drugs.

Results

Seventeen percent of fifth graders reported trying at least 1 substance. Among boys, advanced pubertal stage was associated with increased odds of cigarette, alcohol, or other drug use, whereas delayed school entry was associated with lower odds of any substance, alcohol, or other drug use. Among girls, advanced pubertal stage was associated only with higher odds of alcohol use, and delayed school entry was not associated with substance use. Neither older age for grade or grade retention was independently associated with substance use after controlling for potential confounders.

Conclusion

Advanced pubertal stage may be a more important risk factor for substance use than age for grade. Pediatricians should consider initiating substance use screening earlier for patients with advanced pubertal stage.

Purpose

School social capital incorporates the intangible prosocial resources from social networks, including expectations and social norms, found in a school environment. School social capital may influence health behaviors such as smoking. This study examined the association of school social capital with smoking behaviors from childhood into adolescence.

Methods

We used a cohort sampled from three U.S. cities for the Healthy Passages Longitudinal Study of Adolescent Health. The primary outcome was cigarette smoking at grade 10 (Wave 3). The primary predictor of interest was school social capital at grade 5 (Wave 1). We included potential covariates at the individual, school, and neighborhood levels at Wave 1. To account for simultaneous clustering in schools and neighborhoods, cross-classified multilevel models were used.

Results

After exclusions and imputations for missing variables, our final sample contained 3,968 students as constituents of 118 schools and 479 neighborhoods. With adjustment for the covariates, school social capital for grade 5 was negatively associated with cigarette smoking in grade 10. We estimated that a 1 standard deviation increase in the school average social capital for grade 5 is associated with an odds ratio of .86 (95% credible interval: .75-.98) for school-level smoking in grade 10.

Conclusions

This study suggests that school social capital in late elementary years is associated with reduced smoking behaviors among adolescents in the U.S. Influencing school social capital through enrichment of positive social norms and parent/teacher expectations may be a useful strategy to reduce adolescent smoking, with long-term implications for adult health.