The legacy of minimum legal drinking age law changes: long-term effects on suicide and homicide deaths among women

Relationships of State Alcohol Policy Environments With Homicides and Suicides

INTRODUCTION

Alcohol use is involved in a large proportion of homicides and suicides each year in the U.S., but there is limited evidence on how policies targeting alcohol influence violence in the U.S.

CONTEXT

Extant studies generally focus on individual policies in isolation of each other. This study examines the impacts of changes in states' alcohol policy restrictions on overall homicide and suicide rates and firearm-related homicide and suicide rates using a holistic measure of states' alcohol policy environments.

METHODS

Using a composite measure of state-level alcohol policies (Alcohol Policy Scale) and data from the National Vital Statistics System from 2002 to 2018, this study applied a Bayesian time series model to estimate the impacts of alcohol policy changes on overall and firearm-involved homicide and suicide rates. The analysis was performed in 2023 and 2024.

RESULTS

A 1 SD change in the Alcohol Policy Scale was associated with a 6% decline in homicide rates both overall (incident rate ratio=0.94; 95% credible interval = 0.89, 1.00) and for firearm homicides specifically (incident rate ratio=0.94, 95% CI=0.88, 1.01). There was no clear association of alcohol policy with suicides. The model predicts that a nationwide increase in alcohol restrictions equivalent to a shift from the 25th to 75th percentile of the scale's distribution would result in almost 1,200 fewer homicides annually.

CONCLUSIONS

Increases in the restrictiveness of state-level alcohol policies are associated with reductions in homicides. More restrictive alcohol policy environments may offer an opportunity to reduce homicides.

The Impact of Aggregate Level Alcohol Consumption on Homicide Rates: A Time Series Analysis

Consumption of alcohol has an impact on violent crimes and homicides. The study examines the association between aggregate level consumption of spirit and homicide rates in the State of Kerala in India. Time-series analyses were conducted by building Autoregressive Moving Average with Exogenous Variables (ARMAX) models and OLS Regression models to explain the relationship between the monthly rate of consumption of alcoholic spirits and homicide rates. The study concludes that consumption of alcoholic spirits has a statistically significant impact on the total homicide rates and the male and female homicide rates. The study has significant policy implications being one of the first studies examining the relationship between alcohol consumption and homicide rates in India and suggesting methods to address challenges of adverse public health consequences associated with alcohol consumption.

Examining the Intended and Unintended Impacts of Raising a Minimum Legal Drinking Age on Primary and Secondary Societal Harm and Violence from a Contextual Policy Perspective: A Scoping Review

Raising a minimum legal drinking age (MLDA) has generated interest and debate in research and politics, but opposition persists. Up to now, the presentation of impacts focussed on effectiveness (i.e., intended impact); to our knowledge, no literature syntheses focussed on both intended and unintended impacts. A systematic scoping review was conducted in which a search strategy was developed iteratively and literature was obtained from experts in alcohol research and scientific and grey databases. Ninety-one studies were extracted and analysed using formative thematic content analysis. Intended impacts were reported in 119 units of information from the studies (68% positive), forming four paths: implementation, primary and (two) on secondary societal harm and violence. Unintended developments were reported in 43 units of information (30% positive), forming five themes. Only eight studies reported on implementation. Furthermore, a division between primary and secondary paths and the use of a bridging variable (drinking patterns in analyses or methodology) was discovered. These results provide an insight into how well legislation works and can be used to discover or implement new means of curbing underage drinking and alcohol-related violence and harm. They also offer valuable starting points for future research and underline the importance of considering unintended developments.

Age, period and cohort effects in firearm homicide and suicide in the USA, 1983–2017

Background

Rates of firearm homicide and suicide have varied over time. These variations are due to a number of factors including temporal trends, age, birth year and gender. We sought to conduct an age–period–cohort analysis to understand the intersection of these factors with firearm homicide and suicide.

Methods

We used data on firearm homicide and suicide for the years 1983–2017 from the Centers for Disease Control and Prevention’s Web-based Injury Statistics Query and Reporting System for this analysis. We restricted our analysis on firearm homicide to persons aged 10–44 years and our analysis on firearm suicide to persons aged 50–84 years, as these age groups are most at risk of each outcome. We calculated annual incidence rates for both outcomes per 100 000 population, overall and by gender.

Results

Across all age groups, rates of firearm homicide increased dramatically in the late 1980s and early 1990s. The peak age for firearm homicide varied across cohorts, although it was generally between ages 15 and 29 years. Rates of firearm homicide were substantially higher among men than women, regardless of age, period or cohort. Firearm suicide rates varied significantly by gender. Among men, older cohorts had higher firearm suicide rates, although the rate of firearm suicide increased with age across all cohorts. Among women, firearm suicide rates were also highest among older cohorts; however, firearm suicide rates decreased or remained relatively constant with age.

Conclusion

There are important differences in rates of firearm homicide and suicide with respect to gender, age, period and cohort.

Assessing the impacts of minimum legal drinking age laws on police-reported violent victimization in Canada from 2009 to 2013

BACKGROUND/AIM

Given that alcohol-related victimization is highly prevalent among young adults, the current study aimed to assess the potential impacts of Minimum Legal Drinking Age (MLDA) laws on police-reported violent victimization events among young people.

DESIGN

A regression-discontinuity (RD) approach was applied to victimization data from the Canadian Uniform Crime Reporting 2 (UCR2) Incident-based survey from 2009-2013. Participants/cases: All police-reported violent victimization events (females: n = 178,566; males: n = 156,803) among youth aged 14-22 years in Canada.

MEASUREMENTS

Violent victimization events, primarily consisting of homicide, physical assault, sexual assault, and robbery.

RESULTS

In comparison to youth slightly younger than the drinking age, both males and females slightly older than MLDA had significant and immediate increases in police-reported violent victimization events (females: 13.5%, 95% CI: 7.5%-19.5%, p < 0.001; males: 11.6%, 95% CI: 6.6%-16.7%, p < 0.001). Victimizations occurring in the evening rose sharply immediately after the MLDA by 22.8% (95% CI: 9.9%-35.7%, p =  0.001) for females and 19.3% (95% CI: 11.5%-27.2%, p < 0.001) for males. Increases in violent victimization immediately after MLDA were most prominent in bar/restaurant/open-air settings, with victimizations rising sharply by 44.9% (95% CI: 29.5%-60.2%, p < 0.001) among females and 18.3% (95% CI: 7.7%-29.0%, p =  0.001) among males.

CONCLUSIONS

Young people gaining minimum legal drinking age incur immediate increases in police-reported violent victimizations, especially those occurring in the evening and at bar/restaurant/open-air settings. Evidence suggests that increasing the MLDA may attenuate patterns of violent victimization in newly restricted age groups.

Alcohol Policies and Alcohol-Involved Homicide Victimization in the United States

OBJECTIVE

The purpose of this study was to examine the associations between the alcohol policy environment and alcohol involvement in homicide victims in the United States, overall and by sociodemographic groups.

METHOD

To characterize the alcohol policy environment, the presence, efficacy, and degree of implementation of 29 alcohol policies were used to determine Alcohol Policy Scale (APS) scores by state and year. Data about homicide victims from 17 states from 2003 to 2012 were obtained from the National Violent Death Reporting System. APS scores were used as lagged exposure variables in generalized estimating equation logistic regression models to predict the individual-level odds of alcohol involvement (i.e., blood alcohol concentration [BAC] > 0.00% vs. = 0.00% and BAC ≥ 0.08% vs. ≤ 0.079%) among homicide victims.

RESULTS

A 10 percentage point increase in APS score (representing a more restrictive policy environment) was associated with reduced odds of alcohol-involved homicide with BAC greater than 0.00% (adjusted odds ratio [AOR] = 0.89, 95% CI [0.82, 0.99]) and BAC of 0.08% or more (AOR = 0.91, 95% CI [0.82, 1.02]). In stratified analyses of homicide victims, more restrictive policy environments were significantly protective of alcohol involvement at both BAC levels among those who were female, ages 21-29 years, Hispanic, unmarried, victims of firearm homicides, and victims of homicides related to intimate partner violence.

CONCLUSIONS

More restrictive alcohol policy environments were associated with reduced odds of alcohol-involved homicide victimization overall and among groups at high risk of homicide. Strengthening alcohol policies is a promising homicide prevention strategy.

The impact of adolescent exposure to medical marijuana laws on high school completion, college enrollment and college degree completion

BACKGROUND

There is concern that medical marijuana laws (MMLs) could negatively affect adolescents. To better understand these policies, we assess how adolescent exposure to MMLs is related to educational attainment.

METHODS

Data from the 2000 Census and 2001-2014 American Community Surveys were restricted to individuals who were of high school age (14-18) between 1990 and 2012 (n=5,483,715). MML exposure was coded as: (i) a dichotomous "any MML" indicator, and (ii) number of years of high school age exposure. We used logistic regression to model whether MMLs affected: (a) completing high school by age 19; (b) beginning college, irrespective of completion; and (c) obtaining any degree after beginning college. A similar dataset based on the Youth Risk Behavior Survey (YRBS) was also constructed for confirmatory analyses assessing marijuana use.

RESULTS

MMLs were associated with a 0.40 percentage point increase in the probability of not earning a high school diploma or GED after completing the 12th grade (from 3.99% to 4.39%). High school MML exposure was also associated with a 1.84 and 0.85 percentage point increase in the probability of college non-enrollment and degree non-completion, respectively (from 31.12% to 32.96% and 45.30% to 46.15%, respectively). Years of MML exposure exhibited a consistent dose response relationship for all outcomes. MMLs were also associated with 0.85 percentage point increase in daily marijuana use among 12th graders (up from 1.26%).

CONCLUSIONS

Medical marijuana law exposure between age 14 to 18 likely has a delayed effect on use and education that persists over time.

Alcohol Policies and Suicide: A Review of the Literature

Both intoxication and chronic heavy alcohol use are associated with suicide. There is extensive population-level evidence linking per capita alcohol consumption with suicide. While alcohol policies can reduce excessive alcohol consumption, the relationship between alcohol policies and suicide warrants a critical review of the literature. This review summarizes the associations between various types of alcohol policies and suicide, both in the United States and internationally, as presented in English-language literature published between 1999 and 2014. Study designs, methodological challenges, and limitations in ascertaining the associations are discussed. Because of the substantial between-states variation in alcohol policies, U.S.-based studies contributed substantially to the literature. Repeated cross-sectional designs at both the ecological level and decedent level were common among U.S.-based studies. Non-U.S. studies often used time series data to evaluate pre-post comparisons of a hybrid set of policy changes. Although inconsistency remained, the published literature in general supported the protective effect of restrictive alcohol policies on reducing suicide as well as the decreased level of alcohol involvement among suicide decedents. Common limitations included measurement and selection bias and a focus on effects of a limited number of alcohol policies without accounting for other alcohol policies. This review summarizes a number of studies that suggest restrictive alcohol policies may contribute to suicide prevention on a general population level and to a reduction of alcohol involvement among suicide deaths.

The Impact of the Minimum Legal Drinking Age on Alcohol-Related Chronic Disease Mortality

BACKGROUND

The minimum legal drinking age (MLDA) of 21 has been associated with a number of benefits compared to lower MLDAs, including long-term effects, such as reduced risk for alcoholism in adulthood. However, no studies have examined whether MLDA during young adulthood is associated with mortality later in life. We examined whether individuals exposed to permissive MLDA (<21) had higher risk of death from alcohol-related chronic disease compared to those exposed to the 21 MLDA. Because prior work suggests that MLDA affects college students differently, we also conducted conditional analyses based on ever having attended college.

METHODS

Data from the 1990 through 2010 U.S. Multiple Cause-of-Death files were combined with data on the living population and analyzed. We included individuals who turned 18 during the years 1967 to 1990, the period during which MLDA varied across states. We examined records on death from several alcohol-related chronic diseases, employing a quasi-experimental approach to control for unobserved state characteristics and stable time trends.

RESULTS

Individuals who reported any college attendance did not exhibit significant associations between MLDA and mortality for the causes of death we examined. However, permissive MLDA for those who never attended college was associated with 6% higher odds for death from alcoholic liver disease, 8% higher odds for other liver disease, and 7% higher odds for lip/oral/pharynx cancers (odds ratio [OR] = 1.06, 95% confidence interval [CI] [1.02, 1.10]; OR = 1.08, 95% CI [1.03, 1.13]; OR = 1.07, 95% CI [1.03, 1.12], respectively).

CONCLUSIONS

The 21 MLDA likely protects against risk of death from alcohol-related chronic disease across the lifespan, at least for those who did not attend college. This is consistent with other work that shows that the long-term association between MLDA and alcohol-related outcomes is specific to those who did not attend college.

Did the 18 Drinking Age Promote High School Dropout? Implications for Current Policy

OBJECTIVE

Disagreement exists over whether permissive minimum legal drinking age (MLDA) laws affected underage adolescents (e.g., those age 17 years with the MLDA of 18). We used MLDA changes during the 1970s and 1980s as a natural experiment to investigate how underage exposure to permissive MLDA affected high school dropout.

METHOD

MLDA exposure was added to two data sets: (a) the 5% public use microdata samples of the 1990 and 2000 censuses (n = 3,671,075), and (b) a combined data set based on the 1991-1992 National Longitudinal Alcohol Epidemiological Survey (NLAES) and the 2001-2002 National Epidemiological Survey on Alcohol and Related Conditions (NESARC; n = 16,331). We used logistic regression to model different thresholds of MLDA on high school dropout. We also estimated models conditioned on demographic variables and familial risk of developing alcohol problems.

RESULTS

Only the MLDA of 18 predicted high school dropout. Exposure was associated with 4% and 13% higher odds of high school dropout for the census and NLAES/NESARC samples, respectively. We noted greater impact on women (5%-18%), Blacks (5%-19%), and Hispanics (6%). Self-report of parental alcohol problems was associated with 40% higher odds, which equals a 4.14-point increase in dropout rate for that population.

CONCLUSIONS

The MLDA of 18 likely had a large impact on high school dropout rates, suggesting that the presence of legal-aged peers in a high school setting increased access to alcohol for younger students. Our results also suggest that policy can promote less dangerous drinking behavior even when familial risk of alcohol use disorders is high.

Comparative policy analysis for alcohol and drugs: Current state of the field

BACKGROUND

A central policy research question concerns the extent to which specific policies produce certain effects - and cross-national (or between state/province) comparisons appear to be an ideal way to answer such a question. This paper explores the current state of comparative policy analysis (CPA) with respect to alcohol and drugs policies.

METHODS

We created a database of journal articles published between 2010 and 2014 as the body of CPA work for analysis. We used this database of 57 articles to clarify, extract and analyse the ways in which CPA has been defined. Quantitative and qualitative analysis of the CPA methods employed, the policy areas that have been studied, and differences between alcohol CPA and drug CPA are explored.

RESULTS

There is a lack of clear definition as to what counts as a CPA. The two criteria for a CPA (explicit study of a policy, and comparison across two or more geographic locations), exclude descriptive epidemiology and single state comparisons. With the strict definition, most CPAs were with reference to alcohol (42%), although the most common policy to be analysed was medical cannabis (23%). The vast majority of papers undertook quantitative data analysis, with a variety of advanced statistical methods. We identified five approaches to the policy specification: classification or categorical coding of policy as present or absent; the use of an index; implied policy differences; described policy difference and data-driven policy coding. Each of these has limitations, but perhaps the most common limitation was the inability for the method to account for the differences between policy-as-stated versus policy-as-implemented.

CONCLUSION

There is significant diversity in CPA methods for analysis of alcohol and drugs policy, and some substantial challenges with the currently employed methods. The absence of clear boundaries to a definition of what counts as a 'comparative policy analysis' may account for the methodological plurality but also appears to stand in the way of advancing the techniques.

A reexamination of medical marijuana policies in relation to suicide risk

OBJECTIVES

Previous research has suggested that medical marijuana policies lead to reductions in suicide rates. In this study, we further investigate the association between these policies and within-state changes in suicide risk.

METHODS

Data on suicide deaths (n=662,993) from the National Vital Statistics System Multiple Cause of Death files were combined with living population data. Fixed-effects regression methods were employed to control for state differences in suicide rates and national and state secular trends. Analyses extended prior research that suggested a protective effect of medical marijuana policies by incorporating newer data and additional covariates.

RESULTS

After adjustment for race/ethnicity, tobacco control policies, and other covariates, we found no association between medical marijuana policy and suicide risk in the population ages 15 and older (OR=1.000; 95% CI: 0.956, 1.045; p=0.98), among men overall (OR=0.996; 95% CI: 0.951, 1.043; p=0.87) or for any other age-by-sex groups.

CONCLUSION

We find no statistically significant association between medical marijuana policy and suicide risk. These results contradict prior analyses which did not control for race/ethnicity and certain state characteristics such as tobacco control policies. Failure to control for these factors in future analyses would likely bias estimates of the associations between medical marijuana policy and health outcomes.

Long-term effects of minimum legal drinking age laws on marijuana and other illicit drug use in adulthood

BACKGROUND

Exposure to permissive minimum legal drinking age (MLDA) laws (ability to purchase alcohol <21 years) during adolescence can have long-term effects, including heavy alcohol use or alcohol use disorders as adults. We examined whether exposure to permissive MLDA laws during adolescence has long-term effects on illicit drug use and disorders in adulthood.

METHODS

Participants from the 2004-2012 National Survey of Drug Use and Health (NSDUH) were linked with historical state MLDA laws. Participants born in 1949-1972 (age 31-63 years at observation, n = 110,300) were analyzed because they came of legal age for alcohol purchase when changes occurred in state MLDA laws. Logistic regression was used to model drug use measures as a function of exposure to permissive MLDA during adolescence, adjusting for state and birth-year fixed effects, demographics, and salient state characteristics.

RESULTS

Rates of past month use, past year use, and abuse/dependence of marijuana were 4.7%, 7.8%, and 1.2%, respectively. Rates of past month use, past year use, and abuse/dependence of illicit drugs other than marijuana were 2.9%, 6.2%, and 0.7%, respectively. Among the full sample, exposure to permissive MLDA laws was not significantly associated with drug use or abuse/dependence in adulthood. Men exposed to permissive MLDA laws were at 20% increased odds of past year illicit drug use (aOR 1.20, 95% CI 1.09-1.32).

CONCLUSIONS

Restricting alcohol access during adolescence did not increase long-term drug use. Allowing the purchase of alcohol among those less than 21 years of age could increase the risk of drug use later in life.

Intended and Unintended Effects of State-Mandated High School Science and Mathematics Course Graduation Requirements on Educational Attainment

Mathematics and science course graduation requirement (CGR) increases in the 1980s and 1990s might have had both intended and unintended consequences. Using logistic regression with Census and American Community Survey (ACS) data (n = 2,892,444), we modeled CGR exposure on (a) high school dropout, (b) beginning college, and (c) obtaining any college degree. Possible between-groups differences were also assessed. We found that higher CGRs were associated with higher odds to drop out of high school, but results for the college-level outcomes varied by group. Some were less likely to enroll, whereas others who began college were more likely to obtain a degree. Increased high school dropout was consistent across the population, but some potential benefit was also observed, primarily for those reporting Hispanic ethnicity.

Use of alcohol before suicide in the United States

PURPOSE

Few studies have compared acute use of alcohol in suicide decedents with that in a nonsuicide group. This study provides the first national analysis of acute use of alcohol before suicide compared with an estimate of acute use of alcohol in a living sample.

METHODS

Pooled 2003-2011 National Violent Death Reporting System data were used to estimate the prevalence of postmortem blood alcohol content positivity (blood alcohol content >0.0 g/dL) and intoxication (blood alcohol content ≥0.08 g/dL). Population estimates of comparable use of alcohol (within the past 48 hours) were based on the National Epidemiologic Survey on Alcohol and Related Conditions.

RESULTS

Compared with the living sample, male and female suicide decedents showed, respectively, a 1.83-fold (95% confidence interval [CI], 1.73-1.93) and 2.40-fold (95% CI, 2.24-2.57) increased risk of alcohol ingestion before their death after age, race/ethnicity, and chronic alcohol problems were controlled. Furthermore, male and female decedents exhibited, respectively, a 6.18-fold (95% CI, 5.57-6.86) and a 10.04-fold (95% CI, 8.67-11.64) increased risk of being intoxicated before their death after confounders were considered.

CONCLUSIONS

The findings underscore the crucial need to include among the essential components of suicide prevention policies programs that minimize the use of alcohol, particularly drinking to intoxication.

Long-term impact on alcohol-involved crashes of lowering the minimum purchase age in New Zealand

OBJECTIVES

We assessed the long-term effect of lowering the minimum purchase age for alcohol from age 20 to age 18 years on alcohol-involved crashes in New Zealand.

METHODS

We modeled ratios of drivers in alcohol-involved crashes to drivers in non-alcohol-involved crashes by age group in 3 time periods using logistic regression, controlling for gender and adjusting for multiple comparisons.

RESULTS

Before the law change, drivers aged 18 to 19 and 20 to 24 years had similar odds of an alcohol-involved crash (P = .1). Directly following the law change, drivers aged 18 to 19 years had a 15% higher odds of being in an alcohol-involved crash than did drivers aged 20 to 24 years (P = .038). In the long term, drivers aged 18 to 19 years had 21% higher odds of an alcohol-involved crash than did the age control group (P ≤ .001). We found no effects for fatal alcohol-involved crashes alone and no trickle-down effects for the youngest group.

CONCLUSIONS

Lowering the purchase age for alcohol was associated with a long-term impact on alcohol-involved crashes among drivers aged 18 to 19 years. Raising the minimum purchase age for alcohol would be appropriate.

Alcohol and the law

Society has had an interest in controlling the production, distribution, and use of alcohol for millennia. The use of alcohol has always had consequences, be they positive or negative, and the role of government in the regulation of alcohol is now universal. This is accomplished at several levels, first through controls on production, importation, distribution, and use of alcoholic beverages, and second, through criminal laws, the aim of which is to address the behavior of users themselves. A number of interventions and policies reduce alcohol-related consequences to society by regulating alcohol pricing, targeting alcohol-impaired driving, and limiting alcohol availability. The legal system defines criminal responsibility in the context of alcohol use, as an enormous percentage of violent crime and motor death is associated with alcohol intoxication. In recent years, recovery-oriented policies have aimed to expand social supports for recovery and to improve access to treatment for substance use disorders within the criminal justice system. The Affordable Care Act, also know as "ObamaCare," made substantial changes to access to substance abuse treatment by mandating that health insurance include services for substance use disorders comparable to coverage for medical and surgical treatments. Rather than a simplified "war on drugs" approach, there appears to be an increasing emphasis on evidence-based policy development that approaches alcohol use disorders with hope for treatment and prevention. This chapter focuses on alcohol and the law in the United States.

Long-term effects of laws governing youth access to tobacco

OBJECTIVES

We sought to examine the association between policies governing access to tobacco during adolescence and subsequent adult smoking.

METHODS

We analyzed adult smoking data from the 1998 through 2006-2007 administrations of the US Current Population Survey Tobacco Use Supplement by employing a quasi experimental approach. Participants (n = 105,519) were adults, aged 18 to 34 years at the time of the survey. Smoking outcomes included having ever smoked 100 cigarettes, smoking at the time of the survey, and having smoked 10 or more cigarettes a day conditioned on being an ever smoker. These were predicted from exposure to state youth access policies at age 17 years.

RESULTS

Four of the 9 policies exhibited significant associations with reduced prevalence of 1 or more smoking outcomes, primarily among women. Lesser effects for other policies could not be ruled out.

CONCLUSIONS

Restrictions on youth access to tobacco might lead to reduction in smoking prevalence later in adulthood. The effect might be limited to women; we estimate that having all policies in place could be associated with a 14% reduction in lifetime smoking prevalence for women, and an additional 29% reduction in heavy smoking among ever smokers.

Acute use of alcohol and methods of suicide in a US national sample

OBJECTIVES

We explored age, gender, and racial/ethnic differences with alcohol use and firearms, hanging or asphyxiation, and poisoning methods of suicide.

METHODS

We analyzed data for 37,993 suicide decedents aged 18 years and older from the 2005-2010 National Violent Death Reporting System database. Multinomial logistic regressions examined associations of method with alcohol use defined by blood alcohol content. Two-way interactions tested the effects of age, gender, and race/ethnicity on the associations between alcohol use and method of suicide.

RESULTS

Alcohol was present among decedents who used the 3 leading methods of suicide: firearm (35.0%), hanging (36.8%), and poisoning (32.7%). Two-way interaction tests suggested that in young and middle adulthood, individuals were more likely to drink alcohol when they used a firearm or hanging (compared with poisoning), but in older adulthood, the reverse was true, with alcohol use more likely with poisoning. Interaction tests also suggested that Asians and Pacific Islanders were most likely to use alcohol in poisonings and that Blacks were least likely to use alcohol in hangings.

CONCLUSIONS

The results suggested that alcohol use before suicide was influenced by several factors, including age, race/ethnicity, and suicide method.

The persistent effects of minimum legal drinking age laws on drinking patterns later in life

BACKGROUND

Exposure to permissive minimum legal drinking age (MLDA) laws not only affects young adults in the short term, but also later in life; for example, individuals who could legally purchase alcohol before the age of 21 are more likely to suffer from drinking problems as older adults, long after the laws had been changed. However, it is not known how permissive MLDA exposure affects specific drinking behavior. This present study uses changes in MLDA laws during the 1970s and 1980s as a natural experiment to investigate the potential impact of permissive MLDA exposure on average alcohol consumption, frequency of drinking, and patterns of binging and more moderate, nonheavy drinking.

METHODS

Policy exposure data were paired with alcohol use data from the 1991 to 1992 National Longitudinal Alcohol Epidemiologic Survey and the 2001 to 2002 National Epidemiologic Survey on Alcohol and Related Conditions. Past-year drinkers born between 1949 and 1972 (n = 24,088) were included. Average daily intake, overall drinking frequency, and frequency of both binge episodes (5+ drinks) and days without a binge episode (nonheavy drinking) for the previous year at the time of interview were tracked for each respondent.

RESULTS

Exposure to permissive MLDAs was associated with higher odds to report frequent binging and lower odds to report any moderate drinking; these associations were largely driven by men and those who did not attend college. Overall drinking frequency and average alcohol consumption were not affected by MLDA exposure.

CONCLUSIONS

The ability to legally purchase alcohol before the age of 21 does not seem to increase overall drinking frequency, but our findings suggest that it is associated with certain types of problematic drinking behaviors that persist into later adulthood: more frequent binge episodes and less frequent nonheavy drinking. We also propose that policymakers and critics should not focus on college drinking when evaluating the effectiveness of MLDAs.

Birth cohort effects on adolescent alcohol use: the influence of social norms from 1976 to 2007

CONTEXT The substantial changes in adolescent alcohol use prevalence over time suggest that population-level environmental factors are important determinants of use, yet the potential influence of such environmental factors is inadequately understood. OBJECTIVE To investigate whether adolescents in birth cohorts and/or time periods characterized by restrictive social norms toward alcohol were at decreased risk for alcohol use and binge drinking, controlling for individual attitudes (disapproval) toward use. DESIGN, SETTING, AND PARTICIPANTS In 32 annual national surveys of US high school students, a total of 967 562 students contributed outcome data from 1976 through 2007. MAIN OUTCOME MEASURES Frequency of past-year alcohol use and any instance of binge drinking (≥5 drinks) in the past 2 weeks, analyzed using multilevel models clustering individuals within periods and birth cohorts. Period- and cohort-specific social norm scores (indicating the proportion disapproving of weekend binge drinking) were modeled as predictors, controlling for individual attitudes and demographic characteristics. RESULTS Individuals who matured in birth cohorts with more restrictive social norms were less likely to use alcohol compared with individuals who matured in cohorts with more permissive norms; each 5% increase in the cohort-specific disapproval was associated with a 12% decrease in the odds of past-year alcohol use (odds ratio = 0.88; 99% CI, 0.87-0.89). The effects of cohort-specific disapproval were notably stronger among white adolescents than nonwhite adolescents. CONCLUSIONS This study documents the importance of considering time-varying population-level risk factors in the study of adolescent alcohol use and indicates that, even after an individual's personal attitudes are accounted for, risk is shaped by cohort effects whereby the norms within the cohort contribute to the risk of adolescent alcohol use.

Commentary on Fitzpatrick and colleagues (2012): Forecasting the effect of the amethyst initiative on college drinking

BACKGROUND

There is considerable evidence that heavy episodic drinking (HED) is a serious problem among college students. Concern with this problem has led 135 college presidents to endorse the Amethyst Initiative, which promotes the lowering of the minimum legal drinking age (MLDA) from 21 to 18. The Amethyst Initiative claims that the current MLDA of 21 encourages underage college students to drink in unsupervised locations where they adopt misconceptions regarding the normative level of student drinking that leads to excessive consumption or HED. The study by Fitzpatrick and colleagues (2012) in this issue challenges this hypothesis by contrasting the potential reduction in misapprehension of the drinking norm against the increase in consumption that would be expected if the MLDA was lowered to 18.

METHODS

This commentary places the Fitzpatrick study within the larger context of the MLDA, noting that full consideration of the lowering the MLDA requires the inclusion of 18- to 20-year-old noncollege youths in the work force and 15- to 17-year-old high school students who will have increased access to alcohol through their 18-year-old peers.

RESULTS

Research suggests that alcohol consumption and its associated problems will increase for 15- to 20-year-olds if the MLDA was lowered. This commentary also identifies alternative strategies for reducing college student HED that do not require lowering the MLDA.

CONCLUSIONS

Although college binge drinking is a significant problem, reducing the drinking age is unlikely to be effective. Instead, it will increase the risk of alcohol problems faced by even younger high school students.