Chapter 8 Alcohol: Social Beverage/Social Drug What Makes a Beverage Alcoholic? Fermentation of sugars by yeasts honey (mead) fruit (wine) grain (beer) alcoholic content limited to about 15% Higher concentrations achieved by distillation spirits alcoholic content up to 95% Table 8.1 Alcohol Use through History Alcohol use dates back thousands of years fermentation is very process simple its discovery was probably accidental. Distillation was perfected during the Middle Ages brandy was the first distilled spirit increases the alcohol content and preserves it 17th C brandy was used to “fortify” wine preserved it during shipping from Portugal to England (Port) Alcohol Use through History In later centuries, gin gained popularity in Europe, as did whiskey in the United States. Serious concern about the adverse consequences of alcohol consumption arose in the late 1700s and took root in the United States as a temperance movement. This movement addressed primarily the drinking of distilled spirits. The differentiation among forms of alcohol drinking became blurred during the nineteenth century, as temperance advocates began to promote a total ban on alcohol consumption. Alcohol Use through History National Prohibition was the law in the United States from 1920 to 1933. Since the end of Prohibition, government regulation has been carried out chiefly through education and the taxation of alcohol. Patterns of Alcohol Consumption Today The demographics of alcohol consumption reveal a large disparity in the drinking habits of the population. About a third do not drink at all, and only about 30 percent of those who drink account for 80 percent of all the alcoholic beverages consumed in the United States. Peak alcohol consumption occurs at ages twenty-one to twenty-two. Past-Month Adolescent Alcohol, Cigarette, and Marijuana Use by Grade. Source: Data from 2006 Monitoring the Future Survey Percentage of Americans Who Have Ever Drunk Alcohol (A Whole Drink). Source: SAMHSA data from 2005 National Survey on Drug Use and Health (NSDUH) Number of Days in the Past 30 in Which Drinkers Consumed 5 or More Drinks, by Age and Gender. Source: SAMHSA data from 2005 NSDUH Binge drinking increases short-term risks (accident, overdose, etc) The Pharmacology of Alcohol Alcohol is a very small molecule, easily soluble in both water and fat. Its absorption into the bloodstream is extremely rapid. The breakdown of alcohol is handled by two enzymes in the stomach and especially in the liver, alcohol dehydrogenase and acetaldehyde dehydrogenase. metabolism by liver, in GI tract metabolism by brain legal limit 0.08%, or 80 mg% Blood alcohol concentration (BAC) after the rapid consumption of different amounts of alcohol by eight adult fasting male subjects.* (Adapted from Wilkinson et al., Journal of Pharmacokinetics and Biopharmaceutics, 5(3):207-224, 1977.) The Pharmacology of Alcohol The rate of alcohol biodegradation is constant (~100mg/hr/kg) and dependent on the activity of alcohol dehydrogenase, which limits the rate of metabolism and excretion no matter what quantity of alcohol is consumed. The level of alcohol in the body is measured by the bloodalcohol concentration (BAC; ml/dl), which is dependent on body weight, rate of consumption and time since the last drink. Table 8.2 The Pharmacology of Alcohol Blood alcohol tests are impractical as part of a field sobriety test, so breath alcohol concentration (BrAC) is used instead (Breathalyzer). BAC is estimated from BrAC using a partition ratio (BAC:BrAC) of 2100:1. Urinalysis is another non-invasive way to estimate BAC, but is most useful for long-term detection of ethanol consumption. Ethyl gluturonide (EtG) is detectable for several days since ingesting alcohol. Effects of Alcohol on the Brain Although alcohol affects several neurotransmitters in the brain, it is presently agreed that the principal effect is stimulation of the GABA receptor. Alcohol also acts as an indirect antagonist at NMDA receptors, and thus shares some actions with PCP and ketamine. Effects of Alcohol on the Brain Generally, the neural effect of alcohol begins with inhibition of the cerebral cortex, then that of lower brain regions. Alcohol exerts a powerful effect on the cerebellum via its GABA agonistic effects. Cerebellar function is the primary target of behavioral field sobriety tests. Effects of Alcohol on the Brain Inhibition of respiratory systems in the medulla, usually accomplished at BAC levels in the neighborhood of 0.50 percent, results in asphyxiation and death. Acute Physiological Effects loss of body heat (peripheral vasodilation) increased excretion of water increased heart rate constriction of coronary arteries disturbed sleep serious interactions with other drugs. Acute Behavioral Effects exhilaration and excitement talkativeness slurred speech loss of coordination irritability aggressiveness drowsiness sensorimotor impairment impaired judgment Adolescents Often Get Alcohol From Adults 40% of underage drinkers ages 12 to 20,who drank in the past 30 days obtained alcohol at no cost from adults 21 or older > 6% of underage drinkers given alcohol by their parents in the past month The younger the underage drinker, the more likely he or she is to get alcohol from a family member > 30% of 12 to 14 year old drinkers get alcohol from a family member 12% of drinkers age 18 to 20 Risks Associated with Underage Binge Drinking High school students in the U.S. who binge drink frequently are at higher risk for the following outcomes than are students who abstain from drinking: Risky Sexual Behavior Assaults Sexual Assaults Injuries Academic Problems Legal Problems However, no causal connections have been established between all of these outcomes and binge drinking Alcohol-related Fatalities Among Underage Drinkers Motor Vehicle Crashes: About 1,900 deaths Homicides: About 1,600 deaths Suicides: About 300 deaths Alcohol Consumption and Binge Drinking are Common Among College Students Alcohol Consumption: About four in five of all college students drink, including nearly 60 percent of students ages 18 to 20. Binge Drinking: Approximately two of every five college students of all ages—more than 40 percent—have reported engaging in binge drinking at least once during the past 2 weeks. However, colleges vary widely in their binge drinking rates—from 1 percent to more than 70 percent (Wechsler et al., 1994, 1998, 2000b and NSDUH 2006). Excessive Drinking in College (ages 18-24) Leads to Many Adverse Outcomes: Accidents 599,000 students are unintentionally injured under the influence of alcohol each year (about half are students under 21) of those, about 1,700 die each year including those in motor vehicle crashes (about half among students under 21) Excessive Drinking in College (ages 18-24) Leads to Many Adverse Outcomes: Interpersonal 696,000 are assaulted by another student who has been drinking each year (430,000 by a college student under 21) 97,000 are victims of alcohol-related sexual assault or date rape each year (about half among students under 21) 400,000 had unprotected sex as a result of their drinking >100,000 students were too intoxicated to know if they consented to having sex Excessive Drinking in College (ages 18-24) Leads to Many Adverse Outcomes: Other Events About 25 percent report academic consequences of their drinking missing class falling behind doing poorly on exams or papers receiving lower grades overall About 11 percent of drinkers report that they have vandalized property while under the influence of alcohol The Adolescent Brain May be Particularly Vulnerable to the Effects of Alcohol Reactions to Alcohol: Animal Studies: adolescent animals are less sensitive than adults to some of the aversive effects of acute alcohol intoxication e.g. sedation, hangovers, and loss of coordination more sensitive to alcohol’s effects on social facilitation may enjoy the positive sensations more than adults experience fewer of the immediate negative effects that often serve as protective factors for older drinkers. The Adolescent Brain May be Particularly Vulnerable to the Effects of Alcohol Risk-taking: less mature frontal lobes may be more sensitive to the effects of alcohol greater deficits in self regulation judgment reasoning problem solving impulse control impulsive decisions or actions without regard for consequences can put teenagers at serious risk. Social/Environmental Factors Influence Underage Drinking Risk and protective factors for alcohol use shift throughout adolescence. Transitions: moving from elementary to middle and middle to high school may present increased risk for alcohol use Stress: Increased stress may lead to alcohol use Personality traits: Youth with the following characteristics are more likely to consume alcohol than are others Strong desires for new experiences and sensations History of behavior problems Family conflict and/or familial alcohol problems Binge Drinking Among Adolescents is a Global Problem The percentage of 15-16 year old students who report drinking to intoxication is higher than in the U.S. in most European countries Italy, France, and Greece are among European countries in which a smaller proportion of students report having been drunk 10 times or more during the past 12 months than do those in the U.S. Acute Behavioral Effects serious adverse behavioral effects include blackouts significant impairment in attention, judgment and sensorimotor skills increased potential for aggressive or violent acts Other behavioral effects? Why do people (adults over the legal age) drink? Table 8.4 Acute Behavioral Effects Particular attention has been directed toward these problems within a college student population. The relationship between alcohol consumption and sexual desire and performance is a complex one, with differences being observed for men and women. Table 8.3 Alcohol/drug interactions Alcohol and Health Benefits The accumulated evidence of medical research has indicated that there is a reduced risk for coronary heart disease and stroke with moderate consumption of alcohol. Possible health benefits include a reduction of risk for diabetes, dementia, and rheumatoid arthritis. Alcohol and Health Benefits Moderate alcohol consumption has been defined as no more than one drink per day for women and no more than two drinks per day for men. There should be zero tolerance for alcohol consumption among pregnant women. Strategies for Responsible Drinking Despite the potential for alcohol consumption to produce adverse effects, most people can drink alcohol in a responsible way that avoids these harmful consequences. However, the risk of alcohol dependence is always present. Strategies for Responsible Drinking keep track of your consumption drink low-alcoholic beverages (beer, wine) know what you are drinking drink slowly (e.g. alternating alcohol & water) avoid bingeing eat before/while drinking avoid salt (makes you thirstier) take time to taste what you are drinking drink socially rather than alone don’t drink and drive make drinking an adjunct to other activities