Effects on Caffeine on Adolescent Behavior and Physiology

描述(申请人提供)：美国人每年消费超过150亿加仑的苏打水；相当于每人550罐。在过去的30年里，青少年中咖啡因的使用量增加了70%。在这个年龄段，最受欢迎的咖啡因摄入途径是苏打水。除了摄入咖啡因的潜在健康风险外，苏打水往往含有高水平的糖，这会使儿童面临患龋齿和超重的风险。尽管尚不清楚咖啡因本身是否会使人上瘾，但成人和青少年咖啡因使用者的一部分符合《精神疾病诊断和统计手册》-IV药物依赖标准。此外，咖啡因的使用增加了对可卡因、安非他明和尼古丁的敏感性和成瘾。因为糖是一种已知的“自然奖赏”，它激活与滥用药物相似的神经通路，我们假设咖啡因与糖的长期配对导致糖的消耗增加，这可能是通过增加含有添加糖的食品和饮料的强化价值来调节的。本文概述的研究将检验这一假设，并确定青少年是否对咖啡因的影响产生生理和/或心理上的耐受性。12-17岁的儿童将根据自己报告的每日咖啡因摄入量被细分为四分位数。这将使我们能够评估是否存在不同程度的习惯性使用咖啡因导致对咖啡因使用的生理和行为反应的变化。在具体目标1中，将通过对服用安慰剂和三剂量咖啡因的生理(心率、血压和手部震颤)和心理测量进行剂量反应研究。此外，还将评估咖啡因对添加糖的食品和饮料的消费以及对蔗糖的敏感性和喜好的影响。《特定目标2》将测量慢性和急性咖啡因如何调节人们对新饮料的口味偏好。最后，具体目标3将评估含咖啡因和不含咖啡因饮料的相对增强价值。这些研究调查了一组关于青少年摄入咖啡因的生理和行为后果的新问题。此外，这些结果将提供有关咖啡因使用和食物偏好发展之间潜在联系的信息，特别是对高添加糖分的食物和饮料的偏好。获得国立卫生研究院的资助并完成这套研究将通过提供人类摄食行为、行为药理学和成瘾领域的培训，为首席调查员的职业目标做出贡献。这些研究是朝着建立一条独立的研究路线迈出的第一步，该研究涉及研究调节摄食行为的神经机制。此外，这一奖项将展示成为独立调查员和竞争R01拨款所需的资金潜力。

DESCRIPTION (provided by applicant): Americans consume over 15 billion gallons of soda per year; the equivalent of >550 cans per individual. Caffeine use in adolescents has increased by 70% in the past 30 years. Within this age group, the most popular route of caffeine administration is soda. In addition to potential health risks from consuming caffeine, soda tends to contain high levels of sugar, which puts children at risk for dental caries and overweight. Although it is unclear if caffeine itself is addictive, a subset of adult and adolescent caffeine users meet the Diagnostic and Statistical Manual for Mental Disorders-IV criteria for drug dependence. In addition, caffeine usage increases sensitivity and potentiates addiction to cocaine, amphetamine, and nicotine. Because sugar is a known "natural reward" that activates similar neuronal pathways as drugs of abuse, we hypothesize that the long-term pairing of caffeine with sugar leads to enhanced sugar consumption, potentially mediated by increased reinforcing value of foods and beverages containing added sugar. The studies outlined here will test this hypothesis as well as determine whether adolescents develop physiological and/or psychological tolerance to the effects of caffeine. Children ages 12-17 years will be subdivided into quartiles based on their self-reported daily caffeine intake. This will allow us to assess whether there are different levels of habitual caffeine use lead to changes in physiological and behavioral responses to caffeine administration. In Specific Aim 1, a dose response study will be conducted by taking physiological (heart rate, blood pressure, and hand tremor) and psychological measurements in response to administration of placebo and three doses of caffeine. In addition, the effects of caffeine on consumption of foods and beverages containing added sugar and sensitivity to and liking of sucrose will also be assessed. Specific Aim 2 will measure how chronic and acute caffeine modulates taste preferences for novel drinks. Finally, Specific Aim 3 will assess the relative reinforcing value of caffeinated and non-caffeinated beverages. These studies investigate a novel set of questions concerning the physiological and behavioral consequences of caffeine ingestion among adolescents. In addition, these results will provide information on the potential link between caffeine use and the development of food preferences, in particular preference for foods and beverage with high levels of added sugar. Obtaining NIH funding and completing this set of studies will contribute to the Principal Investigator's career goals by providing training in the areas of human ingestive behavior, behavioral pharmacology, and addiction. These studies are a first step toward establishing an independent line of research that involves studying neuronal mechanisms that regulate ingestive behavior. In addition, this award will demonstrate the funding potential necessary to become an independent investigator and to compete for an R01 grant.