Younger age negatively impacts depression-associated exacerbation of hemoglobin A1c levels in type 2 diabetes: Implications for intervention.

Adults with type 2 diabetes (T2DM) and depression are associated with higher hemoglobin A1C (HbA1C ) compared to their nondepressed counterparts. Little is known about related clinical and demographic components contributing to these differences. We examined differences in HbA1C between adults who have T2DM with and without major depression. T tests and chi-square analyses measured differences in HbA1C and clinical/demographic variables. HbA1C was statistically higher in depressed participants compared to nondepressed participants. The difference was no longer statistically significant after controlling for age. Age and HbA1C were negatively correlated across the sample and were still correlated in each group independently. The interaction of age and HbA1C was moderated by depression status. Additionally, mechanisms for diabetes severity differences were assessed using moderation analyses and Blinder-Oaxaca decomposition technique. Seventy-four percent of the mean outcome HbA1C difference between depressed and nondepressed diabetic participants was explained by age. Furthermore, age was negatively correlated with clinical variables, such as diastolic blood pressure and cholesterol. Comparing age to smoking and nonsmoking participants, smokers were statistically younger. Younger adults with T2DM may require more attention regarding self-management, particularly in the context of depression. Depression should be screened and treated among individuals with diabetes since this exacerbates diabetes severity.

The influence of misperceptions about social norms on substance use among school-aged adolescents.

Individuals often have biased perceptions about their peers' behavior. We use an economic equilibrium analysis to study the role social norms play in substance use decisions. Using a nationally representative dataset, we estimate the effect of misperception about friends' alcohol, smoking, and marijuana use on consumption of these substances by youths in grades 7-12. Overestimation of friend's substance use significantly increases adolescent's own use approximately 1 year later, and the estimated effect is robust across specifications including individual-level fixed effects regression. The effect size is bigger for boys than for girls. The estimates for those who initially underestimated the norm suggest the possibility of a rebound/boomerang effect.

Alcohol consumption by youth: Peers, parents, or prices?

Using data from the National Longitudinal Survey of Adolescent to Adult Health, we estimate the effect of peers' alcohol consumption and alcohol prices on the drinking habits of high-school-age youth. We use the two-stage residual inclusion method to account for the endogeneity of peer drinking in nonlinear models. For our sample of high school students, we find that peer effects are statistically and economically significant regarding the choice to participate in drinking but are not significant for the frequency of drinking, including binge drinking. Regarding alcohol prices, even though we have good price variation in our sample, alcohol prices are not found to be significant. The results are important for policymakers who are considering policies to reduce underage drinking, as we conclude that no significant impact on underage drinking will result from low-tax states' increasing excise taxes on alcohol so they are similar to those of high-tax states. Policymakers may choose to focus instead on the influence of peers and changing the social norm behavior.

Identifying peer effects using spatial analysis: the role of peers on risky sexual behavior.

This paper explores the role of peer effects on early sexual debut for a sample of adolescents using data from the National Longitudinal Study on Adolescent Health (Add Health). Most studies analyzing peer influences ignore the "reflection" problem that occurs with studying peer effects. To address the reflection problem, this paper employs a spatial econometric approach to estimate a social interactions model. This is the first study in the literature on adolescent risky sexual behavior to use this approach to estimate peer effects. Similar to other research on peer effects and adolescent risky sexual behavior, this paper finds the existence of peer effects. However, the more vital outcome from this study is that older and male peers increase the likelihood of adolescent early sexual debut, while peers whose mothers are more open about sexual activity decrease adolescent risky sexual behavior. This methodology can help further our knowledge about the social context that influences adolescent sexual behavior.