Dulce Digital: An mHealth SMS-Based Intervention Improves Glycemic Control in Hispanics With Type 2 Diabetes.

OBJECTIVE: Type 2 diabetes is growing in epidemic proportions and disproportionately affects lower-income, diverse communities. Text messaging may provide one of the most rapid methods to overcome the "digital divide" to improve care. RESEARCH DESIGN AND METHODS: A randomized, nonblinded, parallel-groups clinical trial design allocated N = 126 low-income, Hispanic participants with poorly controlled type 2 diabetes to receive the Dulce Digital intervention or usual care (UC). Dulce Digital participants received up to three motivational, educational, and/or call-to-action text messages per day over 6 months. The primary outcome was HbA1c; lipids, blood pressure, and BMI were secondary outcomes. Satisfaction and acceptability were evaluated via focus groups and self-report survey items. RESULTS: The majority of patients were middle-aged (mean age 48.43 years, SD 9.80), female (75%), born in Mexico (91%), and uninsured (75%) and reported less than a ninth-grade education level (73%) and mean baseline HbA1c 9.5% (80 mmol/mol), SD 1.3, and fasting plasma glucose 187.17 mg/dL, SD 64.75. A statistically significant time-by-group interaction effect indicated that the Dulce Digital group achieved a significantly greater reduction in HbA1c over time compared with UC (P = 0.03). No statistically significant effects were observed for secondary clinical indicators. The number of blood glucose values texted in by participants was a statistically significant predictor of month 6 HbA1c (P < 0.05). Satisfaction and acceptability ratings for the Dulce Digital intervention were high. CONCLUSIONS: Use of a simple, low-cost text messaging program was found to be highly acceptable in this sample of high-risk, Hispanic individuals with type 2 diabetes and resulted in greater improvement in glycemic control compared with UC.

Drinking Patterns Across Spring, Summer, and Fall in 462 University Students.

BACKGROUND: Student heavy drinking and associated problems are common at most universities and fluctuate throughout the calendar year, with marked increases during celebrations. Most studies of student drinking are limited to the academic year itself, and relatively few focus specifically on special heavy drinking events. Even fewer studies include drinking during summer break and subsequent school return. METHODS: In the context of an experimental protocol, beginning in January 2014, alcohol-related characteristics were evaluated 8 times over 55 weeks for 462 college freshmen, including periods that incorporated a campus festival, summer, and school return. Baseline predictors of drinking quantities over time included demography, substance use patterns, as well as environmental and attitudinal characteristics. Product-moment correlations evaluated relationships between baseline characteristics and subsequent quantities, and simultaneous entry regression analyses evaluated which characteristics most robustly predicted usual and maximum drinks over time. RESULTS: Maximum drinks per occasion increased 18% from the early spring (4/8/14 to 5/6/14) to the campus festival period (5/7/14 to 6/3/14), decreased 29% in the summer (7/8/14 to 8/5/14), and increased 31% on school return (10/7/14 to 11/4/14). The most robust predictors of higher quantities in regression analyses included items from each of the 3 major domains with the most consistent results seen for most baseline alcohol-related items and descriptive drinking norms (R(2) = 0.20 to 0.31). CONCLUSIONS: These data demonstrate important changes in students' drinking during the calendar year, including expected large increases during the month of a 1-day festival, large decreases over the summer, and resumption of relatively high quantities upon return to school.

Treatment Attendance Among Veterans With Depression, Substance Use Disorder, and Trauma.

OBJECTIVE: Low attendance in psychotherapy, particularly among individuals with comorbid disorders, is a pervasive challenge. The present study examined predictors of treatment attendance in a sample of veterans with depression, substance use disorder, and trauma. METHODS: This is an analysis of data collected as part of a larger clinical trial involving outpatients at a Veterans Administration dual diagnosis clinic. Individuals were excluded if they had significant memory deficits, schizophrenia, bipolar disorder, or substantial travel constraints. Participants (N = 146) received 12 weeks of group-delivered integrated cognitive behavioral therapy for depression and substance use, followed by randomization to 12 additional weeks of individually delivered cognitive behavioral therapy (n = 62) or cognitive processing therapy (n = 61) modified to address substance use and trauma. Participants, therapists, and researchers were not blinded to group assignment. For this study, we included only the 123 participants who were randomized into the second phase, analyzing predictors of treatment attendance categorized into predisposing factors, enabling factors, and need factors. RESULTS: Participants were primarily male (89%) and Caucasian (76%) and averaged 47 years old (SD = 12). Forty-four percent had alcohol use disorder, 16% had drug use disorder, and 40% had polysubstance use disorder. Most met criteria for PTSD (82%), with 44% having combat-related trauma, 33% sexual trauma, and 28% other trauma. Treatment attendance did not differ between groups. More education was associated with increased group (r = .19, p = .04) and individual session attendance (r = .28, p = .002). Individuals with chronic housing problems attended fewer group sessions (r = -.19, p = .04), while individuals with sexual trauma, compared to those with other traumas, attended more individual sessions (r = .23, p = .01). Number of group sessions attended was positively associated with individual session attendance. CONCLUSIONS: Few variables were significantly predictive of treatment attendance, possibly due to the complex nature of comorbid disorders. Including a focus on trauma was not associated with lower attendance. Special consideration may need to be given to education level, homelessness, and trauma when trying to engage and retain patients with comorbid disorders in treatment. This clinical trial is registered at www.clinicaltrials.gov as NCT00958217.

The Low Level of Response to Alcohol-Based Heavy Drinking Prevention Program: One-Year Follow-Up.

OBJECTIVE: Heavy drinking is common on college campuses, with a marked increase from high school to freshman year. Programs addressing heavy campus drinking often personalize prevention protocols to fit a student's demography and prior drinking characteristics. Few efforts have individualized approaches to address a person's vulnerability through his or her low level of response (low LR) to alcohol. METHOD: This article describes the recently completed 55-week outcome in drinking quantities and problems for the >90% of 500 participants in a prevention program at a U.S. university (62% female, mean age = 18 years) who completed a 4-week series of 50-minute videos delivered via the Internet. We evaluated whether, for low LRs, participation in an educational approach that focused on a low LR (the LR-based [LRB] condition) was associated with better outcomes than a state-of-the-art (SOTA) general education or with a no-intervention control condition. RESULTS: Using a mixed-design analysis of variance and focusing on the most closely ethnically matched high and low LR pairs, students with low LRs in the LRB condition demonstrated the greatest decreases in usual and maximum drinks over the 55 weeks, especially when compared with closely ethnically matched students with high LRs. Low LR controls showed the highest drinking values over time. CONCLUSIONS: This study underscores the potential importance of targeting a person's specific preexisting vulnerability toward heavy drinking when he or she enters college. The approach can be used in a relatively inexpensive protocol of video education sessions delivered via the Internet.

Behavioral economic predictors of brief alcohol intervention outcomes.

OBJECTIVE: The present study attempted to determine whether behavioral economic indices of elevated alcohol reward value, measured before and immediately after a brief alcohol intervention, predict treatment response. METHOD: Participants were 133 heavy drinking college students (49.6% female, 51.4% male; 64.3% Caucasian, 29.5% African American) who were randomized to 1 of 3 conditions: motivational interviewing plus personalized feedback (brief motivational interventions; BMI), computerized personalized feedback intervention (electronic check-up to go; e-CHUG), and assessment only. RESULTS: Baseline level of alcohol demand intensity (maximum consumption) significantly predicted drinks per week and alcohol problems at 1-month follow-up and baseline relative discretionary expenditures on alcohol significantly predicted drinks per week and alcohol problems at 6-month follow-up. BMI and e-CHUG were associated with an immediate postsession reduction in alcohol demand (p < .001, ηp2 = .29) that persisted at the 1-month follow-up, with greater postsession reductions in the BMI condition (p = .02, ηp2 = .06). Reductions in demand intensity and Omax (maximum expenditure) immediately postintervention significantly predicted drinking reductions at 1-month follow up (p = .04, ΔR2 = .02, and p = .01, ΔR2 = .03, respectively). Reductions in relative discretionary expenditures on alcohol at 1-month significantly predicted drinking (p = .002, ΔR2 = .06,) and alcohol problem (p < .001, ΔR2 = .13) reductions at the 6-month follow-up. CONCLUSIONS: These results suggest that behavioral economic reward value indices may function as risk factors for poor intervention response and as clinically relevant markers of change in heavy drinkers.

The impact of focusing a program to prevent heavier drinking on a pre-existing phenotype, the low level of response to alcohol.

BACKGROUND: Heavy drinking is common during transitions from high school to college. Optimal programs for diminishing risks for high alcohol consumption often tailor the approach to the specific needs of students. This study describes the results of an Internet-based prevention protocol that tailors the information to the risk associated with a pre-existing phenotype, the Low level of Response (Low LR) to alcohol. METHODS: Using stratified random assignment, 454 freshmen with Low and High LR values were assigned to 2 education groups (LR-based where all examples were given the context of the Low LR model of heavy drinking or a State Of The Art (SOTA) Group where the same lessons were taught but without an emphasis on LR) or a no-intervention Control Group. Individuals in the 2 education groups viewed 50-minute online videos once per week for 4 weeks. Changes in drinking patterns were assessed at Baseline, 4 weeks, and 8 weeks using a 2 (LR status) by 3 (education group) by 3 (time points) analysis of variance, with additional tests for ethnicity and sex. RESULTS: Low LR participants tended to decrease their usual (p < 0.06) and maximum (p < 0.05) drinks per occasion most prominently when assigned to the LR-based protocol, while those with High LRs improved more in the SOTA Group. The most robust differences were seen when controlling for ethnicity. The effect sizes were small to medium. CONCLUSIONS: These results support the advantages of carrying out prevention via the Internet and in tailoring the approach to a pre-existing phenotype.

Chronic physical health problems moderate changes in depression and substance use among dual diagnosed individuals during and after treatment.

BACKGROUND: Physical illnesses frequently co-occur with depression and substance use disorders and may impact their improvement. Physical illness symptoms may overlap with or exacerbate somatic symptoms of depression. Individuals may use substances to cope with symptoms of physical illness. OBJECTIVES: We examined whether chronic physical health problems moderated changes in depression and substance use among dual diagnosed individuals during and in the year following treatment. METHODS: Participants were recruited from a Veterans Affairs dual diagnosis outpatient program between March 2000 and November 2007 and were randomized to either Integrated Cognitive-Behavioral Therapy or Twelve-Step Facilitation Therapy. A total of 214 veterans with assessment data for the variables of interest were included in analyses. Participants completed quarterly depression, substance use, and health assessments over an 18 month period. We used linear-mixed effects models to analyze patterns of change for depression and substance use. RESULTS: Individuals with severe chronic health problems and higher intake depression showed slower improvements in both nonsomatic and somatic depression symptoms. Individuals with severe chronic health problems and higher midtreatment substance use showed less improvement in substance use. CONCLUSIONS: Assessing and addressing physical health issues during depression and substance use disorder treatment may improve outcomes.

Family history of problem drinking is associated with less sensitivity of alcohol demand to a next-day responsibility.

OBJECTIVE: Behavioral economic demand curves measure alcohol consumption as a function of price and may capture clinically relevant individual differences in alcohol-reinforcing efficacy. This study used a novel, behavioral-economic, hypothetical demand-curve paradigm to examine the association between family history of alcohol misuse and individual differences in both alcohol demand and the relative sensitivity of alcohol demand to next-day responsibilities. METHOD: Participants were 207 college students (47% male, 68.5% White, 27.4% African American, Mage = 19.5 years) who reported at least one heavy drinking episode (5/4 or more drinks on one occasion for a man/woman) in the past month and completed two versions of an alcohol purchase task (APT) that assessed hypothetical alcohol consumption across 17 drink prices. In one APT (standard), students imagined they had no next-day responsibilities, and in the other, they imagined having a 10:00 a.m. test the next day. RESULTS: A series of analyses of covariance indicated that participants with at least one biological parent or grandparent who had misused alcohol reported similar levels of alcohol demand on the standard APT but significantly less sensitivity to the next-day academic responsibility as measured by the percentage of reduction in demand intensity and breakpoint across the no-responsibility and next-day-test conditions. CONCLUSIONS: These findings provide initial evidence that APTs might clarify one potential mechanism of risk conferred by family history. Young adult heavy drinkers with a family history of problematic drinking may be less sensitive to next-day responsibilities that might modulate drinking in drinkers without a family history of alcohol problems.

Behavioral economic measures of alcohol reward value as problem severity indicators in college students.

The aims of the current study were to examine the associations among behavioral economic measures of alcohol value derived from 3 distinct measurement approaches, and to evaluate their respective relations with traditional indicators of alcohol problem severity in college drinkers. Five behavioral economic metrics were derived from hypothetical demand curves that quantify reward value by plotting consumption and expenditures as a function of price, another metric measured proportional behavioral allocation and enjoyment related to alcohol versus other activities, and a final metric measured relative discretionary expenditures on alcohol (RDEA). The sample included 207 heavy-drinking college students (53% female) who were recruited through an on-campus health center or university courses. Factor analysis revealed that the alcohol valuation construct comprises 2 factors: 1 factor that reflects participants' levels of alcohol price sensitivity (demand persistence), and a second factor that reflects participants' maximum consumption and monetary and behavioral allocation toward alcohol (amplitude of demand). The demand persistence and behavioral allocation metrics demonstrated the strongest and most consistent multivariate relations with alcohol-related problems, even when controlling for other well-established predictors. The results suggest that behavioral economic indices of reward value show meaningful relations with alcohol problem severity in young adults. Despite the presence of some gender differences, these measures appear to be useful problem indicators for men and women.

Demographic and predeparture factors associated with drinking and alcohol-related consequences for college students completing study abroad experiences.

OBJECTIVE: Study abroad students are at risk for increased and problematic drinking behavior. As few efforts have been made to examine this at-risk population, the authors predicted drinking and alcohol-related consequences abroad from predeparture and site-specific factors. PARTICIPANTS: The sample consisted of 339 students completing study abroad programs. METHODS: Participants filled out online measures at predeparture, abroad, and at postreturn. RESULTS: The authors found that drinking and consequences abroad were predicted by a number of factors, including demographics (eg, younger age, male sex, Greek affiliation, white ethnicity), student factors (eg, low GPA, major area of study), study abroad site factors (eg, apartment living abroad, study in Europe), predeparture levels of drinking and consequences, sensation seeking, and goals related to social gathering. CONCLUSIONS: Findings can be used to inform campus policies for admission to study abroad programs as well as assist in the development of interventions targeted toward preventing risk for students during abroad experiences.

Impact of Physical Health on Treatment for Co-occurring Depression and Substance Dependence.

OBJECTIVE: There is a high rate of comorbidity among substance dependence, depression, and physical health problems. This study aimed to examine the impact of pre-treatment physical health stressors (acute and chronic conditions) on outcomes of treatment in a sample of veterans with dual disorders (depression and substance dependence) who were randomized to integrated cognitive behavioral therapy versus 12-Step interventions. METHODS: This study included 205 veterans (89.8% male, mean age = 49.5 years) enrolled in a clinical treatment outcomes trial. Chronic health problems (persistent, ongoing conditions lasting 2 weeks or more; e.g., arthritis, diabetes) and acute health events (occurring on a discrete date; e.g., injury, surgery, myocardial infarction) were coded dichotomously (presence versus absence) and evaluated separately. The impact of physical health stressors on abstinence (defined dichotomously), percentage of days abstinent, and depression symptoms were analyzed at the end of 12 and 24 weeks of treatment. Additionally, associations between intake motivation to change, health stressors, and substance use were examined. RESULTS: Analyses revealed that participants who had experienced a pretreatment acute health event had higher rates of abstinence at 12-weeks, higher percentage of days abstinent at 24-weeks, and higher depression symptoms at intake. Participants with chronic health difficulties had more severe depression at intake and those participants with severe chronic difficulties had greater depression symptoms across all time points. Chronic health difficulties were related to the Taking Steps factor of motivation to change substance use, but acute health events were not related to motivation to change. Motivation to change was also not related to substance outcomes in our sample. CONCLUSIONS: Physical health appears to have a complex relationship with co-occurring depression and substance dependence. Acute health problems predicted lower substance use, whereas chronic health problems were associated with higher depression levels. Explicitly addressing the connection between substance use and health events during treatment may improve addiction treatment outcomes. However, individuals with chronic health problems may benefit from extending treatment or adjunct strategies focused on addressing chronic health concerns. This is an analysis of data collected as part of a clinical trial registered at www.ClinicalTrials.gov as NCT00108407.

Symptoms of depression and PTSD are associated with elevated alcohol demand.

BACKGROUND: Behavioral economic demand curves measure individual differences in motivation for alcohol and have been associated with problematic patterns of alcohol use, but little is known about the variables that may contribute to elevated demand. Negative visceral states have been theorized to increase demand for alcohol and to contribute to excessive drinking patterns, but little empirical research has evaluated this possibility. The present study tested the hypothesis that symptoms of depression and PTSD would be uniquely associated with elevated alcohol demand even after taking into account differences in typical drinking levels. METHOD: An Alcohol Purchase Task (APT) was used to generate a demand curve measure of alcohol reinforcement in a sample of 133 college students (50.4% male, 64.4% Caucasian, 29.5% African-American) who reported at least one heavy drinking episode (5/4 or more drinks in one occasion for a man/woman) in the past month. Participants also completed standard measures of alcohol consumption and symptoms of depression and PTSD. RESULTS: Regression analyses indicated that symptoms of depression were associated with higher demand intensity (alcohol consumption when price=0; ΔR(2)=.05, p=.002) and lower elasticity (ΔR(2)=.04, p=.03), and that PTSD symptoms were associated with all five demand curve metrics (ΔR(2)=.04-.07, ps<.05). CONCLUSIONS: These findings provide support for behavioral economic models of addiction that highlight the role of aversive visceral states in increasing the reward value of alcohol and provide an additional theoretical model to explain the association between negative affect and problematic drinking patterns.

The impact of elevated posttraumatic stress on the efficacy of brief alcohol interventions for heavy drinking college students.

Brief alcohol interventions (BAIs) have been widely adopted for use with college students and are associated with significant reductions in drinking and problems. However, many students do not respond to these approaches and little is known about risk factors for poor response. The current study investigated one possible risk factor by examining the impact of posttraumatic stress (PTS) symptoms on BAI efficacy. This study presents pooled data from two randomized clinical trials that examined the efficacy of counselor-administered BAIs compared with computerized interventions. Participants were 207 college students (53.1% women, 68.1% White/Caucasian, 16.9% with elevated post-traumatic stress) who reported past-month heavy episodic drinking. Follow-up assessments were completed six months post-intervention. Analyses testing differences in frequency of past-month heavy episodic drinking revealed a significant post-traumatic stress by time interaction (F(1,165)=8.27, p=.005) such that individuals screening positive for PTS showed larger reductions in heavy episodic drinking at follow-up. A significant three-way interaction between time, PTS, and intervention condition (F(2,167)=5.76, p=.004) was found for alcohol related consequences. Specifically, among individuals screening positive for PTS, only those that received the counselor-administered BAI showed a significant reduction in consequences at follow-up. These results suggest that overall college students with PTS may respond well to BAIs and that counselor-delivered BAIs may be more efficacious than computer-delivered interventions for reducing alcohol problems for these high-risk students.

Alcohol-related consequences in African American and European American college students.

Approximately 50% of college students report a heavy drinking episode in the past 2 weeks. This pattern of heavy episodic drinking places them at risk for experiencing alcohol-related problems. In addition, important ethnic differences exist between European American and African American college students in terms of drinking. European American college students report consuming more alcohol than African American college students, but little research exists on the differences in types and rates of problems. The current study sought to examine the differences in problems among 451 African American and European American college students using a comprehensive measure of alcohol-related problems. The effect of gender was also examined as research has found consistent gender differences in drinking. European American students experienced more problems overall and greater levels of social/interpersonal problems and risky behaviors even after controlling for drinking level. In addition, women reported significantly greater levels of problems in all domains except physical dependence, risky behaviors, and self-perception when drinking was controlled for.

A randomized controlled trial of a behavioral economic supplement to brief motivational interventions for college drinking.

OBJECTIVE: Behavioral economic theory suggests that a reduction in substance use is most likely when there is an increase in rewarding substance-free activities. The goal of this randomized controlled clinical trial was to evaluate the incremental efficacy of a novel behavioral economic supplement (Substance-Free Activity Session [SFAS]) to a standard alcohol brief motivational interviewing (BMI) session for heavy-drinking college students. METHOD: Participants were 82 first-year college students (50% female; 81.7% White/European American; M age = 18.5 years, SD = 0.71) who reported 2 or more past-month heavy drinking episodes. After completing a baseline assessment and an individual alcohol-focused BMI, participants were randomized to either the SFAS or to a Relaxation Training (RT) control session. The SFAS was delivered in an MI style and attempted to increase the salience of delayed academic and career rewards and the patterns of behavior leading to those rewards. RESULTS: The combination of an alcohol BMI plus the SFAS was associated with significantly greater reductions in alcohol problems compared with an alcohol BMI plus RT at the 1-month and 6-month follow-up assessments (p = .015, ηp² = .07), an effect that was partially mediated by increases in protective behavioral strategies. BMI + SFAS was also associated with greater reductions in heavy drinking among participants who at baseline reported low levels of substance-free reinforcement or symptoms of depression. CONCLUSION: These results are consistent with behavioral economic theory and suggest that a single session focused on increasing engagement in alternatives to drinking can enhance the effects of brief alcohol interventions.

A behavioral economic supplement to brief motivational interventions for college drinking.

Basic behavioral and neurobiological research has demonstrated that deficiencies in naturally occurring substance-free rewards are both a cause and a consequence of substance abuse that are due in part to the systematic discounting of delayed substance-free rewards. Existing brief motivational interventions (BMIs) for alcohol abuse do not target this mechanism of change. The goal of this uncontrolled pilot study was to evaluate a behavioral economic Substance-Free Activity Session (SFAS) to traditional alcohol BMIs. Participants were 13 college freshmen who reported two or more heavy drinking episodes (>5/4 drinks in an occasion for men/ women) in the past month. All participants completed a baseline assessment and a BMI that addressed alcohol use. In addition, participants received the SFAS, a 50-min individual session that attempts to increase engagement in constructive alternatives to drinking by enhancing the salience of delayed rewards (academic and career success) and the patterns of behavior (academic and extracurricular engagement) leading to these outcomes. At the 1-month follow-up assessment, participants reported significant reductions in heavy drinking, and moderate to large effect size reductions in weekly drinking and peak blood alcohol levels. The results of this pilot study provide preliminary support for the efficacy of this behavioral economic intervention session as a supplement to traditional alcohol BMIs.

Drinking motives mediate the relationship between reinforcing efficacy and alcohol consumption and problems.

OBJECTIVE: Several studies have shown that demand curve indices of the reinforcing efficacy of alcohol (i.e., reports of hypothetical alcohol consumption and expenditures across a range of drink prices) are associated with alcohol-related outcomes. A next logical step in this area of research is to examine potential mediators of this direct relationship. It is possible that enhancement and coping drinking motives serve as an intermediary of the reinforcing efficacy-alcohol use relationship, such that higher reinforcing efficacy is associated with increased motivation to drink, which is then associated with greater alcohol use and problems. METHOD: Data were collected from 215 college undergraduates who reported drinking in the past 30 days. RESULTS: The demand curve reinforcing efficacy indices O(max) (maximum alcohol expenditure) and intensity (consumption level when drinks were free) demonstrated the strongest and most consistent associations with alcohol use, problems, and motives. Results from two structural equation models indicated that enhancement and coping motives mediated the relationship between reinforcing efficacy and alcohol use and alcohol-related problems. CONCLUSIONS: These results suggest that the motivational effects of the behavioral economic variable reinforcing efficacy on problematic alcohol use are in part mediated by increases in enhancement and coping motives for drinking.

The effect of drink price and next-day responsibilities on college student drinking: a behavioral economic analysis.

More than [3/4] of U.S. college students report a heavy drinking episode (HDE; 5 (for men) and 4 (for women) drinks during an occasion) in the previous 90 days. This pattern of drinking is associated with various risks and social problems for both the heavy drinkers and the larger college community. According to behavioral economics, college student drinking is a contextually bound phenomenon that is impacted by contingencies such as price and competing alternative reinforcers, including next-day responsibilities such as college classes. This study systematically examines the role of these variables by using hypothetical alcohol purchase tasks to analyze alcohol consumption and expenditures among college students who reported recent heavy drinking (N = 207, 53.1% women). The impact of gender and the personality risk factor sensation seeking (SS) were also assessed. Students were asked how many drinks they would purchase and consume across 17 drink prices and 3 next-day responsibility scenarios. Mean levels of hypothetical consumption were highly sensitive to both drink price and next-day responsibility, with the lowest drinking levels associated with high drink prices and a next-day test. Men and participants with greater levels of SS reported more demand overall (greater consumption and expenditures) than women and students with low SS personality. Contrary to our hypotheses women appeared to be less sensitive to increases in price than men. The results suggest that increasing drink prices and morning academic requirements may be useful in preventing heavy drinking among college students.

Reinforcing efficacy moderates the relationship between impulsivity-related traits and alcohol use.

Studies have shown that impulsivity-related traits are associated with alcohol use among college students. It is possible that individual differences in susceptibility to reinforcement from alcohol, which reflects the extent to which an individual values alcohol, moderates this relationship. Data were collected from 255 college students at a large, urban university who reported consuming alcohol at least once in the past 30 days. Two impulsivity-related-traits, Urgency and Sensation Seeking, were examined, as well as the reinforcing efficacy indices of Omax (maximum alcohol expenditure) and Demand Intensity (consumption when price = zero). Findings indicated that Omax moderated the relationship between both impulsivity-related traits and alcohol consumption, and between Urgency and alcohol-related problems. Demand Intensity also moderated the relationship between both impulsivity-related traits and alcohol use, but did not moderate the relationship between either trait and alcohol-related problems. Results from this study suggest that college students high in certain impulsivity-related traits and for whom alcohol is a highly valued reinforcer have a high risk for excessive alcohol consumption and an increased probability of experiencing negative alcohol-related problems.

Relations between heavy drinking, gender, and substance-free reinforcement.

Behavioral economic theory and laboratory research have suggested that substance abuse may be associated with diminished engagement in enjoyable substance-free activities (substance-free reinforcement). However, college students, in particular men, have reported numerous social benefits from drinking that might mitigate the expected inverse relation between drinking and substance-free reinforcement. In this study, we examined the relations between college student heavy drinking, gender, and several categories of substance-free reinforcement (peer, dating, sexual, school, and family activities). Participants were 246 undergraduate students who were classified as a function of their reported frequency of heavy drinking during a typical week in the past month (120 heavy drinkers, 126 light drinkers). Heavy drinking was associated with significantly higher substance-free peer and sexual reinforcement. This association was gender invariant and remained significant in multiple regression models that controlled for gender, ethnicity, and fraternity or sorority membership. Substance-free reinforcement did not predict frequency of heavy drinking in models that included levels of substance-related reinforcement. The results indicate that college student heavy drinking is not associated with global deficits in substance-free reinforcement and is instead associated with increased peer and sexual activity that occurs outside the context of drinking or drug use. Prevention programs should help students to compensate for the potential loss of social reinforcement associated with reductions in drinking.