Comparison of longitudinal phenotypes based on alternate heavy drinking cut scores: a systematic comparison of trajectory approaches III.

The goal of the present study was to empirically determine the effect of employing different cut scores for frequency of heavy episodic drinking (HED; an often-used indicator of problematic alcohol involvement) within a longitudinal framework. Using data from a large prospective (9-wave) college student sample, the authors used latent class growth analyses to characterize developmental trajectories of HED based on alternate cut scores that varied in frequency of HED (defined by 5+ drinks per occasion), as well as to measure very heavy episodic drinking (12+ drinks per occasion). As cut score severity increased and base rates for HED correspondingly decreased, individuals were increasingly categorized into less severe classes. Concordance between trajectories ranged from small to moderate, with concordance using highly discrepant definitions of frequent HED being particularly low. HED trajectories based upon different cut scores were validated against a range of etiological and consequential correlates. No single cut score was superior to others in explaining variance in external validity indicators, suggesting that the choice of cut score should be based upon theoretical and clinical considerations. This study further extends the authors' prior work examining the effects of methodological factors that are critical to characterizing the developmental course of alcohol involvement.     

Drinking trajectories following an initial lapse.

Relapse following alcohol treatment is a major problem for individuals who are alcohol dependent, yet little is known about the course of drinking after the initial lapse. In the current study, discrete-time survival analysis and latent growth mixture modeling were used to evaluate the time to first lapse and the trajectories of postlapse drinking in a sample of 563 individuals who received community alcohol treatment. Results showed a decreasing risk of lapsing over time. After the initial lapse, 3 trajectory subgroups provided a parsimonious representation of the heterogeneity in postlapse drinking frequency and quantity, with the majority of individuals reporting light, infrequent drinking. Covariate analyses incorporating demographics, distal risk factors, time to first lapse, and coping behavior as predictors of time to lapse and postlapse drinking trajectories indicated that alcohol dependence and coping behavior were the strongest predictors of lapsing and postlapse drinking behavior.     

Motivational pathways to alcohol use and abuse among Black and White adolescents

Using data from a biracial community sample of adolescents, the present study examined trajectories of alcohol use and abuse over a 15-year period, from adolescence into young adulthood, as well as the extent to which these trajectories were differentially predicted by coping and enhancement motives for alcohol use among the 2 groups. Coping and enhancement motivations (M. L. Cooper, 1994) refer to the strategic use of alcohol to regulate negative and positive emotions, respectively. Results showed that Black and White youth follow distinct alcohol trajectories from adolescence into young adulthood and that these trajectories are differentially rooted in the regulation of negative and positive emotions. Among Black drinkers, coping motives assessed in adolescence more strongly forecast differences in alcohol involvement into their early 30s, whereas enhancement motives more strongly forecast differences among White drinkers. Results of the present study suggest that different models may be needed to account for drinking behavior among Blacks and Whites and that different approaches may prove maximally effective in reducing heavy or problem drinking among the 2 groups.     

The natural history of cigarette smoking from adolescence to adulthood in a midwestern community sample: multiple trajectories and their psychosocial correlates.

Previous research on the natural history of smoking has focused on overall group trajectories without considering the possibility of risk subgroup variation. To address this limitation, the authors of the present study aimed to identify subgroups with varying trajectories of smoking behavior. The authors accomplished this within a cohort-sequential study of a large community sample (N = 8,556) with measurements spanning ages 11-31. After removing 2 a priori groups (abstainers and erratics), the authors empirically identified 4 trajectory groups--early stable smokers, late stable smokers, experimenters, and quitters--and psychosocial variables from adolescence and young adulthood were significantly distinguished among them. Given recent advances in quantitative methods, it is now feasible to consider subgroups of trajectories within an overall longitudinal design.     

Changes in smoking behaviors from late childhood to adolescence: insights from the Canadian National Longitudinal Survey of Children and Youth.

OBJECTIVE: To examine smoking behaviors in Canadian youth from late childhood to adolescence. By following participants from as young as 10 and 11 years, the authors proposed to identify distinct developmental pathways of smoking acquisition. DESIGN: Growth mixture modeling was used to identify developmental trajectories of smoking among 10- to 17-year-old participants of the Canadian National Longitudinal Survey of Children and Youth. MAIN OUTCOME MEASURES: Developmental trajectories of trying smoking, smoking frequency, and smoking intensity. Results: Five developmental trajectories related to smoking frequency were identified, of which 2 were acquisition patterns that led to daily smoking at age 16-17, and 3 were experimentation patterns that led to nonsmoking at age 16-17. The largest variability in changes in smoking behavior over time was the reported level of smoking frequency. CONCLUSION: Analysis showed that there is more than 1 way in which Canadian children and adolescents acquire smoking behaviors over time. The authors were able to differentiate patterns of experimentation from patterns of acquisition. Whereas experimentation has been generally considered as 1 of the stages in the smoking acquisition process leading to regular smoking, these results indicate that experimentation can be described as a distinct process in itself.     

遗传、环境和青少年的吸烟饮酒行为：芬兰双生子研究的回溯与前瞻

本文介绍的两个“芬兰双生子（Finn Twin）”研究是对10个出生组的青少年双生子及其家庭的长期跟踪研究。本文概述了这两个项目对遗传与环境的关联和互动对吸烟饮酒行为影响的研究。这些研究的结果提示个体差异对吸烟饮酒行为的长期变动的影响受到兄弟姐妹互动、同伴互动以及父母教养方式的调节。环境对吸烟饮酒的影响主要表现在学校、居住社区与家庭环境的差异上。环境与遗传影响的程度和持久度有城乡差异。遗传的影响受居住社区的制约。多阶段模型的分析揭示了遗传与环境的互动对这些行为的演变（从试吸试饮到发展到滥用）的动态的影响,遗传似乎对吸烟饮酒的共同轨迹更有影响。这些结果对今后本项目对这约1万对芬兰成年双生子的分子遗传学研究提供了有益的线索     

The effect of restraint beliefs on alcohol-seeking behavior

Individuals who believe that they have high levels of restraint over motivated behaviors such as cigarette smoking are, paradoxically, more likely to engage in those behaviors when tempted (Nordgren, Van Harreveld, & Van Der Pligt, 2009). Our aim was to experimentally manipulate heavy drinkers' beliefs about their drinking restraint to examine the effect on drinking behavior. Sixty heavy drinkers completed an implicit association test and a stop-signal task before receiving bogus feedback on their task performance that indicated that they had either high or low levels of drinking restraint. Participants then completed a bogus taste test in which they were able to consume beer and a soft drink. Results indicated that the group falsely led to believe that they had a high level of drinking restraint subsequently consumed more beer than the group led to believe that they had a low level of drinking restraint. This study demonstrates that beliefs about drinking restraint can influence drinking behavior, in that individuals who overestimate their control over drinking are at greater risk of drinking to excess when exposed to tempting situations.     

Alcohol use trajectories and the ubiquitous cat's cradle: cause for concern?

In recent years, trajectory approaches to characterizing individual differences in the onset and course of substance involvement have gained popularity. Previous studies have sometimes reported 4 prototypic courses: (a) a consistently "low" group, (b) an "increase" group, (c) a "decrease" group, and (d) a consistently "high" group. Although not always recovered, these trajectories are often found, despite these studies varying in the ages of the samples studied and the duration of the observation periods employed. Here, the authors examined the consistency with which these longitudinal patterns of heavy drinking were recovered in a series of latent class growth analyses that systematically varied the age of the sample at baseline, the duration of observation, and the number and frequency of measurement occasions. Data were drawn from a 4-year, 8-wave panel study of college student drinking (N = 3,720). Despite some variability across analyses, there was a strong tendency for these prototypes to emerge regardless of the participants' age at baseline and the duration of observation. These findings highlight potential problems with commonly employed trajectory-based approaches and the need to not over-reify these constructs.     

Smoking patterns and dependence: contrasting chippers and heavy smokers

The authors used ecological momentary assessment to contrast smoking patterns among chippers (CHs; n = 26)--smokers who smoke despite an apparent absence of tobacco dependence--with those seen in heavy smokers (HSs; n = 28). Smoking and nonsmoking settings (activity, mood, etc.) were assessed by means of electronic diary. CHs were not social smokers; like HSs, they smoked half their cigarettes while alone. When smoking, CHs' urge levels equaled those of HSs; between cigarettes, CHs had few urges, whereas HSs reported moderate urges. CHs' smoking was particularly associated with indulgent activities: relaxation, socializing, eating, and drinking alcohol. Outside of these indulgent settings, CHs' (but not HSs') smoking was associated with negative affect. In idiographic analyses, CHs' smoking was under much stronger stimulus control than was that of HSs. The authors propose that the disappearance of stimulus control over use is a characteristic of dependence.     

Trajectories of alcohol and drug use and dependence from adolescence to adulthood: the effects of familial alcoholism and personality

This study describes trajectories of substance use and dependence from adolescence to adulthood. Identified consumption groups include heavy drinking/heavy drug use, moderate drinking/experimental drug use, and light drinking/rare drug use. Dependence groups include alcohol only, drug only, and comorbid groups. The heavy drinking/heavy drug use group was at risk for alcohol and drug dependence and persistent dependence and showed more familial alcoholism, negative emotionality, and low constraint. The moderate drinking/experimental drug use group was at risk for alcohol dependence but not comorbid or persistent dependence and showed less negative emotionality and higher constraint. Familial alcoholism raised risk for alcohol and drug use and dependence in part because children from alcoholic families were more impulsive and lower in agreeableness.     

Telescoped trajectories from alcohol initiation to disorder in children of alcoholic parents

The current study tested whether and why children of alcoholics (COAs) showed telescoped (adolescent) drinking initiation-to-disorder trajectories as compared with non-COAs. Using longitudinal data from a community-based sample, the authors confirmed through survival analyses that COAs progressed more quickly from initial adolescent alcohol use to the onset of disorder than do matched controls. Similar risks for telescoping were evident in COAs whose parents were actively symptomatic versus those whose parents had been previously diagnosed. Stronger telescoping effects were observed for COAs whose parents showed comorbidity for either depression or antisocial personality disorder. Both greater externalizing symptoms and more frequent, heavier drinking patterns at initiation failed to explain COAs' risk for telescoping, although externalizing symptoms were a unique predictor of telescoping. This risk for telescoping was also evident for drug disorders. These findings characterize a risky course of drinking in COAs and raise important questions concerning the underlying mechanisms and consequences of telescoping in COAs.     

Integration of impulsivity and positive mood to predict risky behavior: development and validation of a measure of positive urgency

In 3 studies, the authors developed and began to validate a measure of the propensity to act rashly in response to positive affective states (positive urgency). In Study 1, they developed a content-valid 14-item scale, showed that the measure was unidimensional, and showed that positive urgency was distinct from impulsivity-like constructs identified in 2 models of impulsive behavior. In Study 2, they showed that positive urgency explained variance in risky behavior not explained by measures of other impulsivity-like constructs, differentially explained positive mood-based risky behavior, differentiated individuals at risk for problem gambling from those not at risk, and interacted with drinking motives and expectancies as predicted to explain problem drinking behavior. In Study 3, they confirmed the hypothesis that positive urgency differentiated alcoholics from both eating-disordered and control individuals.     

The Heritability of Human Behavior: Results of Aggregating Meta-Analyses

The heritability of human behavior can be estimated through studies comparing MZ and DZ twins and through adoption studies. Meta-analyses have estimated the heritability of intelligence, mental chronometric performance, language ability, anxiety disorders, major depression, antisocial behavior, problem drinking, and smoking. This article presents the aggregation and analysis of these meta-analyses, which included a total of over four hundred samples. The results of the aggregation suggest that about 41% of human behavior is genetically influenced, a percentage that may have evolutionary value. Some significant moderators were found in more than one meta-analysis, including greater heritability (a) in more disordered levels of a behavior for performance on a language-ability test, antisocial behavior, and smoking and (b) in females for antisocial behavior and smoking initiation. The moderator findings raise questions about what might explain the identified differences in level of heritability.     

The relationship between drinking control strategies and college student alcohol use.

Interventions designed to reduce heavy drinking among college students often contain suggestions for drinking control strategies. However, little is known about the relationship between the use of these strategies and alcohol consumption. The authors developed a measure of drinking control strategies and investigated its psychometric properties in a sample of 250 college drinkers. Strategies clustered into three factors: selective avoidance of heavy drinking activities and situations, strategies used while drinking, and alternatives to drinking. These three types of strategies were independently associated with alcohol use; however, the first and last types were negatively associated with alcohol consumption, whereas the second type was positively associated with alcohol use. The findings from this study suggest that the type of strategy recommended may be important when the goal is alcohol reduction.     

Thinness and eating expectancies predict subsequent binge-eating and purging behavior among adolescent girls

One's expectancies for reinforcement from eating or from thinness are thought to represent summaries of one's eating-related learning history and to thus influence the development of binge-eating and purging behavior. In a 3-year longitudinal study, the authors tested this hypothesis and the hypothesis that binge eating also influences subsequent expectancy development. The authors used trajectory analysis to identify groups of middle school girls who followed different trajectories of binge eating, purging, eating expectancies, and thinness expectancies. Initial eating and thinness reinforcement expectancies identified girls whose binge eating and purging increased during middle school, and expectancies differentiated girls who began these problem behaviors from girls who did not. Initial binge-eating scores differentiated among eating expectancy developmental trajectories. The onset of most behaviors can be understood in terms of learned expectancies for reinforcement from these behaviors. The same model can be applied to the risk for eating disorders.     

Etiological contributions to heavy drinking from late adolescence to young adulthood

The authors examined genetic and environmental contributions to stability and change in heavy drinking from late adolescence to young adulthood in a sample of 1,152 twin pairs. In men, heavy drinking was similarly heritable at ages 17 (h2=.57) and 20 (h2=.39), and its stability owed primarily to common genetic factors. In women, heavy drinking was less heritable than in men at ages 17 (h2=.18) and 20 (h2=.30) and its stability was primarily due to enduring shared environmental influences. P3 amplitude, an event-related brain potential marker of alcoholism risk, was less predictive of heavy drinking in women than in men, providing further support for the proposition that biological factors have less impact on heavy drinking in young adult women than in young adult men.     

A randomized motivational enhancement prevention group reduces drinking and alcohol consequences in first-year college women.

Alcohol consumption among college students has become an increasing problem that requires attention from college administrators, staff, and researchers. Despite the physiological differences between men and women, college women are drinking at increasingly risky rates, placing them at increased risk for negative consequences. The current study tested a group motivational enhancement approach to the prevention of heavy drinking among 1st-year college women. Using a randomized design, the authors assigned participants either to a group that received a single-session motivational enhancement intervention to reduce risky drinking that focused partly on women's specific reasons for drinking (n = 126) or to an assessment-only control group (n = 94). Results indicated that, relative to the control group participants, intervention participants drank fewer drinks per week, drank fewer drinks at peak consumption events, and had fewer alcohol-related consequences over a 10-week follow-up. Further, the intervention, which targeted women's reasons for drinking, was more effective in reducing consumption for participants with high social and enhancement motivations for drinking.     

Identifying two potential mechanisms for changes in alcohol use among college-attending and non-college-attending emerging adults

This study tested whether pro-alcohol peer influences and prosocial involvement account for increases in drinking during the transition into emerging adulthood and whether these mechanisms differ depending on college attendance and/or moving away from home. The authors used structural equation modeling of prospective data from 825 young men and women. For 4 groups defined by college and residential status, more drinking in the spring of 12th grade predicted more pro-alcohol peer influences the following fall, and more pro-alcohol peer influences in the fall predicted increases in drinking the following spring. Going to college while living at home was a protective factor against increases in drinking and selection of pro-alcohol peer involvements. Prosocial involvement (measured by involvement in religious activities and volunteer work) was not significantly related to post-high school drinking except among college students living away from home. Prevention efforts should focus on (a) reducing opportunities for heavy drinking for college and noncollege emerging adults as they leave home and (b) increasing prosocial involvement among college students not living at home.     

Changes in heavy drinking over the third decade of life as a function of collegiate fraternity and sorority involvement: a prospective, multilevel analysis.

Although affiliation with a fraternity or sorority is an important risk factor for heavy drinking, recent research indicates that this risk may be limited to the college years. Random coefficient growth modeling was used to track changes in patterns of heavy drinking over the course of 11 years as a function of gender and collegiate Greek involvement (N=318). Overall, greater cumulative exposure to the Greek system led to increased heavy drinking during the college years, particularly among men. Shortly after leaving college, heavy drinking levels dropped markedly and remained low through approximately age 30. Inclusion of peer alcohol use norms in the model reduced the influence of Greek involvement. Implications for models of heavy drinking and health risks are discussed.     

Is heavy drinking really associated with attrition from college? The alcohol-attrition paradox

Student attrition at colleges across the United States poses a significant problem for students and families, higher educational institutions, and the nation's workforce competing in the global economy. Heavy drinking is a highly plausible contributor to the problem. However, there is little evidence that it is a reliable predictor of attrition. Notably, few studies take into account indicators of collegiate engagement that are associated with both heavy drinking and persistence in college. Event-history analysis was used to estimate the effect of heavy drinking on attrition among 3,290 undergraduates at a large midwestern university during a 4-year period, and student attendance at a number of college events was included as covariates. Results showed that heavy drinking did not predict attrition bivariately or after controlling for precollege predictors of academic success. However, after controlling for event attendance (an important indicator of collegiate engagement), heavy drinking was found to predict attrition. These findings underscore the importance of the college context in showing that heavy drinking does in fact predict attrition and in considering future intervention efforts to decrease attrition and also heavy drinking.