Adolescent caffeine use and problematic school behavior: A longitudinal analysis of student survey data and teacher observations.

INTRODUCTION: Caffeine is a psychostimulant possessing arousal, motor activation, and reinforcing properties, which is consumed daily by most adolescents aged 12-19 years. Although current understanding of the implications of adolescent caffeine consumption for school behaviors remains incomplete, studies have shown that in addition to acute effects of the drug, in common with other habit-forming psychoactive substances, regular use leads to physical dependence, evidenced by recurring negative withdrawal symptoms. METHODS: Employing two waves of longitudinal data, we tested the prospective association between daily caffeine use and homeroom teacher-observed self-control and problem behavior in a sample of middle-school students in 20 schools in West Virginia in the United States. Caffeine was operationalized with two dichotomized variables, daily consumption of <100 mg, and daily consumption of >100 mg, versus no daily use. Gender, mother's education, family financial status, social support by primary caregiver and adults in school, and school climate, were applied as covariates in linear mixed models. RESULTS: Daily caffeine use of >100 mg was robustly and inversely associated with self-control and positively associated with problem behavior. CONCLUSIONS: Caffeine consumption and associated withdrawal symptoms may be an important factor in problematic school behavior among adolescents. Recent advent of highly concentrated caffeine products (e.g., caffeine "shots") commonly marketed directly at youth, should give rise to concerns including consideration about limiting caffeine consumption among children and youth.

Caffeine consumption and onset of alcohol use among early adolescents.

Preventing or delaying the onset of alcohol use among children and youth is an important public health goal. One possible factor in alcohol use onset among early adolescents is caffeine. The aim of this study was to assess the possible contribution of caffeine to the onset of alcohol use during early adolescence. We used data from the Young Mountaineer Health Study Cohort. Survey data were collected from 1349 (response rate: 80.7%) 6th grade students (mean age at baseline 11.5 years) in 20 middle schools in West Virginia during the fall of 2020, and again approximately 6 months later in spring of 2021. We limited our analyses to students reporting never having used any form of alcohol at baseline. Logistic regression was employed in multivariable analyses and both Odds Ratios and Relative Risks reported. At follow-up, almost 14% of participants reported having consumed alcohol at least once and 57% used caffeine of 100 mg + daily. In multivariable analyses we controlled for social and behavioral variables known to impact tobacco use. Caffeine use was operationalized as a three-level factor: no use, <100 mg per day, and 100 + mg per day, with the latter being the approximate equivalent of the minimum of a typical cup of coffee or can of energy drink. Caffeine use of 100 mg + per day was significantly related to alcohol use at 6-months follow-up (OR: 1.79, RR: 1.56, p = .037). We conclude that caffeine consumption among 11-12-year-old adolescents may be a factor in early onset of alcohol use.

Adolescent caffeine consumption and aggressive behavior: A longitudinal assessment.

Background: Adolescent caffeine consumption has been linked to aggressive behaviors, although no longitudinal tests have been reported to date. The purpose of this study was to test the longitudinal relations between daily adolescent caffeine consumption and aggressive behaviors. Methods: Two waves of survey data collected 12 months apart in the spring of 2018 and 2019, from the 2004 birth cohort in the Icelandic LIFECOURSE study, were analyzed using structural equation modeling (N = 2,278). Both direct and mediated models were employed. Results: Caffeine use at time 1 (T1) was associated with aggressive behavior at time 2 (T2) (ß = .12, p < .001) independent of aggressive behavior at T1. A considerable added relation was observed between caffeine at T1 and aggressive behavior at T2 via indirect (i.e., mediated) effects of aggressive behavior at T1 (standardized ß = .20, p < .001). Over 64% of the standardized total effect (ß = .31) observed between caffeine at T1 and aggressive behavior at T2 was due to mediation. Conclusion: Adolescent caffeine consumption forecasts aggressive behaviors. Caffeine use at T1 increased the likelihood of self-reported aggressive behaviors 12 months later irrespective of level of reported aggressive behavior at T1 while controlling for common confounders.

Disclosing conflict of interest does not mitigate healthcare bias and harm: It is time to sever industry ties.

Disclosing conflict of interest is widely believed to mitigate bias and harm from industry entanglement in healthcare research, education and practice. However, evidence is lacking of disclosure-related mitigation. Radical and extensive severing of industry ties to health care is necessary to curtail industry-related bias and harm.

Can public financing of the private sector defeat antimicrobial resistance?

Public financing to incentivise private sector innovation in antimicrobial pharmaceuticals is believed by many to be necessary to defeat growing threats from antimicrobial resistance. Large cash incentives from the public sector are said to be essential to stimulate 'normal' market forces capable of unleashing much-needed innovation. However, there is little evidence to suggest that lack of innovation in drug development is peculiar to antimicrobials or that current deficits in the supply of antimicrobials is due to unique inefficiencies in the antimicrobial market. Neither the history of drug development in general nor of antimicrobial innovation in particular supports economic interventions intended to stimulate private sector supply of new antimicrobials. On the contrary, public underwriting of the private sector, which by definition is compelled to prioritise profit, risks dire consequences for future global health.

Reviving Cochrane's contribution to evidence-based medicine: bridging the gap between evidence of efficacy and evidence of effectiveness and cost-effectiveness.

Throughout the quarter century since the advent of evidence-based medicine (EBM), medical research has prioritized 'efficacy' (i.e. internal validity) using randomized controlled trials. EBM has consistently neglected 'effectiveness' and 'cost-effectiveness', identified in the pioneering work of Archie Cochrane as essential for establishing the external (i.e. clinical) validity of health care interventions. Neither Cochrane nor other early pioneers appear to have foreseen the extent to which EBM would be appropriated by the pharmaceutical and medical devices industries, which are responsible for extensive biases in clinical research due to selective reporting, exaggeration of benefits, minimization of risks, and misrepresentation of data. The promise of EBM to effect transformational change in health care will remain unfulfilled until (i) studies of effectiveness and cost-effectiveness are pursued with some of the same fervour that previously succeeded in elevating the status of the randomized controlled trial, and (ii) ways are found to defeat threats to scientific integrity posed by commercial conflicts of interest.

A gender-specific analysis of adolescent dietary caffeine, alcohol consumption, anger, and violent behavior.

Self-reported dietary caffeine and alcohol consumption were examined in relation to anger and violent behavior in Icelandic tenth-graders. Structural equation modeling (SEM) was used to investigate direct and indirect effects of measured and latent variables in the population sample of 3,670, controlling for parental financial standing, family structure, ADHD, and peer delinquency. Gender differences were observed that have not been reported previously, especially in relation to anger as a possible mediator of violent behavior against a background of caffeine and alcohol consumption. Study findings suggest the need to take account of caffeine consumption in relation to adolescent anger and violence.

Caffeinated sugar-sweetened beverages and common physical complaints in Icelandic children aged 10-12 years.

OBJECTIVE: Consumption of caffeinated sugar-sweetened beverages (CSSBs) among children and adolescents has increased markedly in recent years but the consequence of their consumption is not well understood. The objective of this study was to assess the prevalence of CSSBs in children aged 10­12 years and examine the relationship between CSSBs and common physical complaints. METHODS: Data from the 2013 cross-sectional population school survey Youth in Iceland (N=11,267, response rate: 90.1%, girls 49.7%)was used to assess the prevalence of cola and energy drink consumption and associations to headaches, stomachaches, sleeping problems and low appetite. RESULTS: Around 19% of boys and 8% of girls reported consuming cola drinks on a daily basis and 7% of boys and 3% of girls reported consuming energy drinks. A general trend of a dose­response relationship was observed between CSSBs and physical complaints for both types of beverages. These relationships were generally stronger for energy drinks than cola drinks. CONCLUSION: Our findings call into question the acceptability, availability, and marketing of CSSBs to 10­12 year-old children and adolescents. For validation purposes replications of these analyses are needed in other parts of the world, including studies using prospective longitudinal designs.