Neighborhood of residence and risk of initiation into injection drug use among street-involved youth in a Canadian setting

Background

While research has suggested that exposure to environments where drug use is prevalent may be a key determinant of drug-related risk, little is known regarding the impact of such exposure on the initiation of illicit injection drug use. We assessed whether neighborhood of residence predicted rates of injecting initiation among a cohort of street-involved youth in Vancouver, British Columbia.

Methods

We followed street-involved injecting naïve youth aged 14–26 and compared rates of injecting initiation between youth residing in Vancouver's Downtown Eastside (DTES) neighborhood (the site of a large street-based illicit drug market) to those living in other parts of the city. Univariate and multivariate Cox regression analyses were employed to determine whether residence in the DTES was independently associated with increased risk of initiation of injection drug use.

Results

Between September, 2005 and November, 2011, 422 injection-naïve individuals were followed, among whom 77 initiated injecting for an incidence density of injecting of 10.3 (95% confidence interval [CI] 5.0–18.8) per 100 person years. In a multivariate model, residence in the DTES was independently associated with initiating injection drug use (adjusted hazard ratio [AHR] = 2.16, 95% CI: 1.33–3.52, p = 0.002).

Conclusions

These results suggest neighborhood of residence affects the risk of initiation into injection drug use among street-involved youth. The development of prevention interventions should target high-risk neighborhoods where risk of initiating into injecting drug use may be greatest.     

Risk factors for progression to regular injection drug use among street-involved youth in a Canadian setting

Background

Street-involved youth are at high risk for experimenting with injection drug use; however, little attention has been given to identifying the factors that predict progression to on-going injecting.

Methods

Logistic regression was used to identify factors associated with progression to injecting weekly on a regular basis among a Canadian cohort of street-involved youth.

Results

Among our sample of 405 youth who had initiated injecting at baseline or during study observation, the median age was 22 years (interquartile range [IQR] = 21–24), and 72% (293) reported becoming a regular injector at some point after their first injection experience. Of these, the majority (n = 186, 63%) reported doing so within a month of initiating injection drug use. In multivariate analysis, the drug used at the first injection initiation event (opiates vs. cocaine vs. methamphetamine vs. other; all p > 0.05) was not associated with progression; however, younger age at first injection (adjusted odds ratio [AOR] = 1.13), a history of childhood physical abuse (AOR = 1.81), prior regular use of the drug first injected (AOR = 1.77), and having a sexual partner present at the first injection event (AOR = 2.65) independently predicted progression to regular injecting.

Conclusion

These data highlight how quickly youth progress to become regular injectors after experimentation. Findings indicate that addressing childhood trauma and interventions such as evidence-based youth focused addiction treatment that could prevent or delay regular non-injection drug use, may reduce progression to regular injection drug use among this population.     

Is opioid substitution treatment beneficial if injecting behaviour continues?

Background

Opioid substitution treatment (OST) is recognised as an effective treatment for opioid dependence. Still, a subgroup of OST users continues to inject drugs. This study examines health risks and criminal activity in a population of needle exchange programme (NEP) participants by comparing those identified as current OST users to (i) those identified as former OST users and (ii) those with no OST experience.

Methods

This was a semi-annual cross-sectional study conducted from 2002 to 2011. NEP participants were interviewed in Oslo, Norway (n = 1760); 341 were identified as current OST users, 356 as former OST users and 1063 had no OST experience. The associations between OST status and health risk and criminal activity were assessed through univariate and multiple logistic regression analyses.

Results

Among NEP participants, those currently in OST had fewer non-fatal overdoses (OR = 0.5 [95% CI 0.3, 0.9]) compared to former OST users and those never in OST. Additionally, they were less likely to have injected frequently (OR = 0.4 [95% CI 0.3, 06]), to have used heroin daily or almost daily (OR = 0.3 [95% CI 0.2, 0.4]), and to have committed theft (OR = 0.6 [95% CI 0.4, 1.0]) and engaged in drug dealing (OR = 0.7 [95% CI 0.5, 0.9]) in the past month. Overall, there was a high level of polysubstance use and no group differences on this measure.

Conclusions

NEP participants who are currently in OST have substantially reduced health risks and criminal activity than other NEP participants. The high level of polysubstance use nevertheless poses a public health challenge.     

Prevalence and factors related to syringe sharing behaviours among female injecting drug users who are also sex workers in China

Background

Female injecting drug users who are sex workers (IDUFSWs) are at high risk of contracting HIV. They may bridge HIV transmissions from injecting drug users to clients of female sex workers.

Methods

A total of 216 non-institutionalised IDUFSWs were recruited by snowball sampling methods. Anonymous face-to-face interviews were conducted to collect data. Univariate, multivariate and hierarchical logistic regression models were fitted to investigate the associations between background characteristics, cognitive variables, psychological stress and syringe sharing behaviours among IDUFSWs.

Results

Respectively 33.8% and 27.8% of the respondents injected drugs with others’ used syringes and gave used syringes to others for drug injection in the last month. These two syringe sharing behaviours were significantly associated with inconsistent condom use during commercial sex (OR = 5.00 and 1.92, p < 0.05). Over 90% of the respondents reported at least one type(s) of psychological distress included in this study. Adjusting for significant background variables, all variables that are related to the Theory of Planned Behaviour (attitude, norm, perceived control and behavioural intention) and psychological distress (except for depression) were significantly associated with injecting drugs with others’ used syringes (adjusted OR = 2.08-6.25, p < 0.05), whilst variables related to perceived control, behavioural intention and insomnia were significantly associated with providing used syringes to others for injection (adjusted OR = 2.00-3.56, p < 0.05). In two separate summary multivariate models, variables related to the Theory of Planned Behaviours and psychological distress were independently associated with injecting drugs with others’ used syringes (OR = 1.98-4.02, p < 0.05) and giving used syringes to others for injection (OR = 2.06-3.59, p < 0.05).

Conclusions

Syringe sharing behaviours were prevalent among IDUFSWs and were associated with cognitive and psychological factors. Effective integrative intervention programmes targeting IDUFSWs are warranted.     

Intentions to quit smoking among youth in substance abuse treatment

Introduction

Smoking cessation interventions for adolescents in substance abuse treatment have shown promise. However, a better understanding of the correlates of substance use disordered (SUD) youths’ intentions toward smoking cessation will help tailor cessation interventions to this population. The current study examined tobacco use, smoking-related self-efficacy, substance use and intentions to quit using alcohol and illicit drugs as correlates of intentions to quit smoking among youth in SUD treatment.

Methods

Participants were 178 adolescents who were in inpatient (n = 90) or outpatient (n = 88) SUD treatment and had smoked at least once in the past 30 days. The sample was 44% female, 72% non-Hispanic Caucasian, with a mean age of 16.2 years (SD = 1.2). Participants rated the likelihood that they would be nonsmokers in the next year (9-point scale).

Results

SUD youth intention to quit smoking averaged 4.9 out of 10 (SD = 3.2), comparable to intention to quit drinking (M = 5.3, SD = 3.6), but lower than their intention to quit using drugs (M = 6.0, SD = 3.4). Teens’ intentions to quit smoking were associated with nicotine dependence (r = −.30, p < .01) and smoking cessation related self-efficacy (r = .36, p < .01), but not with pretreatment substance use severity (r = −.15). Controlling for nicotine dependence, teens’ intentions to quit smoking were positively related to smoking cessation self-efficacy (pr = .26, p < .01) and intention to quit using illicit drugs (pr = .15, p < .05), but unrelated to intention to quit drinking.

Discussion

Findings highlight the appropriateness of addressing adolescent tobacco use during SUD treatment, but emphasize the importance of assessing intention and other cognitions for each substance, as they may differ markedly.     

Patterns of injection drug use cessation during an expansion of syringe exchange services in a Canadian setting

Background

Needle and syringe programmes (NSPs) have been shown to reduce HIV risk among people who inject drugs (IDUs). However, concerns remain that NSPs delay injecting cessation.

Methods

Individuals reporting injection drug use in the past six months in the greater Vancouver area were enrolled in the Vancouver Injection Drug Users Study (VIDUS). Annual estimates of the proportion of IDU reporting injecting cessation were generated. Generalized estimating equation (GEE) analysis was used to assess factors associated with injecting cessation during a period of NSP expansion.

Results

Between May 1996 and December 2010, the number of NSP sites in Vancouver increased from 1 to 29 (P < 0.001). The estimated proportion of participants (n = 2710) reporting cessation increased from 2.4% (95% confidence interval [CI]: 0.0–7.0%) in 1996 to 47.9% (95% CI: 46.8–48.9%) in 2010 (P < 0.001). In a multivariate GEE analysis, the authors observed an association between increasing calendar year and increased likelihood of injecting cessation (Adjusted Odds Ratio = 1.17, 95% CI: 1.15, 1.19, P < 0.001).

Conclusion

The proportion of IDU reporting injecting cessation increased during a period of NSP expansion, implying that increased NSP availability did not delay injection cessation. These results should help inform community decisions on whether to implement NSPs.     

A tale of two stimulants: Mentholated cigarettes may play a role in cocaine,but not methamphetamine,dependence

Background

Research suggests that mentholated cigarettes may play a role in cocaine dependence. The purpose of the present study was to expand upon the research on mentholated cigarettes and cocaine dependence and to evaluate the role of mentholated cigarettes in methamphetamine dependence.

Methods

Secondary analysis of a multisite, randomized trial evaluating the impact of smoking-cessation treatment in stimulant-dependent outpatients (N = 538). Participants’ reasons for concurrent use of cigarettes and illicit stimulants were assessed via self-report. Stimulant-abstinence was measured by self-report and urine drug screens. Smoking cessation was assessed via self-report and carbon monoxide levels.

Results

Of the 301 cocaine-dependent participants, 201 (67%) were menthol and 100 (33%) were non-menthol cigarette smokers. Cocaine-dependent participants who smoked menthol, compared to non-menthol, cigarettes were significantly more likely to report that cigarettes prolong their cocaine high (X²(1) = 16.3, p < .0001, OR = 3.58 [95% CI: 1.88–6.79]) and were less likely to be stimulant abstinent during active treatment (W = 3.6, p < 0.001, d = .39 [95% CI: 0.16–0.62]), at 3-month follow-up (X²(1) = 14.4, p < 0.001, OR = .32 [95% CI: 0.17–0.58]), and at 6-month follow-up (X²(1) = 4.6, p = 0.03, OR = .53 [95% CI: 0.29–0.95]). No parallel differences were found between menthol and non-menthol methamphetamine-dependent smokers. The prevalence of Caucasian menthol smokers was significantly greater in the cocaine-dependent participants (37.2%) than in the methamphetamine-dependent participants (17.61%), (X²(1) = 14.4, p < .001, OR = 2.77 [95% CI:1.62–4.73]). Smoking cessation was not significantly associated with cigarette type for either cocaine- or methamphetamine-dependent participants.

Conclusions

The present results suggest that mentholated cigarettes play a role in cocaine, but not methamphetamine, dependence.     

Association between nicotine replacement therapy use in pregnancy and smoking cessation

Background

There is an urgent need to find better ways of helping pregnant smokers to stop. Randomized controlled trials (RCTs) have not detected an effect of nicotine replacement therapy (NRT) for smoking cessation in pregnancy. This may be because of inadequate dosing because of faster nicotine metabolism in this group. In England, many pregnant smokers use single form and combination NRT (patch plus a faster acting form). This correlational study examined whether the latter is associated with higher quit rates.

Methods

Routinely collected data from 3880 pregnant smokers attempting to stop in one of 44 Stop Smoking Services in England. The outcome measure was 4-week quit rates, verified by expired-air carbon monoxide level < 10 ppm. Outcome was compared between those not using medication versus using single form NRT (patch or one of the faster acting forms), or combination NRT. Potential confounders were intervention setting (specialist clinic, home visit, primary care, other), intervention type (one-to-one, group, drop-in, other), months pregnant, age, ethnicity and occupational group in multi-level logistic regressions.

Results

After adjustment, combination NRT was associated with higher odds of quitting compared with no medication (OR = 1.93, 95% CI = 1.13–3.29, p = 0.016), whereas single NRT showed no benefit (OR = 1.06, 95% CI = 0.60–1.86, p = 0.84).

Conclusions

Use of a combination of nicotine patch and a faster acting form may confer a benefit in terms of promoting smoking cessation during pregnancy. While this conclusion is based on correlational data, it lends support to continuing this treatment option pending confirmation by an RCT.     

Differences between abstinent and non-abstinent individuals in recovery from alcohol use disorders

Objective

Non-abstinent goals can improve quality of life (QOL) among individuals with alcohol use disorders (AUDs). However, prior studies have defined “recovery” based on DSM criteria, and thus may have excluded individuals using non-abstinent techniques that do not involve reduced drinking. Furthermore, no prior study has considered length of time in recovery when comparing QOL between abstinent and non-abstinent individuals. The current aims are to identify correlates of non-abstinent recovery and examine differences in QOL between abstainers and non-abstainers accounting for length of time in recovery.

Sample

A large (N = 5380) national sample of individuals who self-describe as “in recovery” from alcohol problems recruited in the context of the What Is Recovery? (WIR) study.

Method

Multivariate stepwise regressions estimating the probability of non-abstinent recovery and average quality of life.

Results

Younger age (OR = 0.72), no prior treatment (OR = 0.63) or AA (OR = 0.32), fewer dependence symptoms (OR = 0.17) and less time in recovery all significantly (P < 0.05) related to non-abstinent recovery. Abstainers reported significantly (P < 0.05) higher QOL than non-abstainers (B = 0.39 for abstinence vs. non-abstinence), and abstinence was one of the strongest correlates of QOL, even beyond sociodemographic variables like education.

Conclusions

Non-abstainers are younger with less time in recovery and less problem severity but worse QOL than abstainers. Clinically, individuals considering non-abstinent goals should be aware that abstinence may be best for optimal QOL in the long run. Furthermore, time in recovery should be accounted for when examining correlates of recovery.     

Understanding the role of cessation fatigue in the smoking cessation process

Background

To understand the dynamic process of cessation fatigue (i.e., the tiredness of trying to quit smoking) with respect to its average trend, effect on relapse, time-varying relations with craving and negative affect, and differences among genders and treatment groups.

Method

Randomized placebo-controlled clinical trial. Participants received either placebo, monotherapy (bupropion SR, nicotine patch, nicotine lozenge), or combined pharmacotherapy (bupropion SR + nicotine lozenge, nicotine patch + nicotine lozenge). Data were collected from 1504 daily smokers who were motivated to quit smoking. The participants completed baseline assessments and ecological momentary assessments for 2 weeks post-quit.

Results

Cessation fatigue reduced the likelihood of 6-month post-quit abstinence (OR = 0.97, 95% CI (0.95, 0.99)), and was positively associated with craving and negative affect. After controlling for these two factors, average cessation fatigue increased over time. Compared to men, women experienced greater fatigue (t = −10.69, p < 0.0001) and a stronger relation between fatigue and craving (t = −8.80, p < 0.0001). The relationship between fatigue and negative affect was significantly stronger in men (t = 5.73, p < 0.0001). Cessation fatigue was significantly reduced by combined pharmacotherapy (t = −13.4, p < 0.0001), as well as monotherapy (t = −6.2, p < 0.0001).

Conclusions

Cessation fatigue was closely related to craving, negative affect, and cessation outcomes. Women reported greater cessation fatigue than men. Current treatments appeared to reduce fatigue and weaken its relations with craving and negative affect.     

Treatment seeking adults with autism or ADHD and co-morbid Substance Use Disorder: Prevalence,risk factors and functional disability

Background

Little is known about Autism Spectrum Disorder (ASD) in adults, especially not about ASD with co-morbid Substance Use Disorder (SUD). We wanted to examine how adults with ASD compare to adults with ADHD on prevalence and risk factors for co-morbid SUD, and on disability levels associated with SUD.

Methods

We stratified 123 treatment seeking adults with ASD (n = 70) or ADHD (n = 53), into current, former and no history of SUD (SUD+, SUD^∧, and SUD−), and conducted interviews to explore associated risk factors and current levels of disability.

Results

Prevalence of co-morbid SUD was higher in ADHD than in ASD in our sample (58% versus 30%, p = 0.001). There was no statistically significant difference between ASD and ADHD in risk factors or disability scores. Patients with lifetime SUD started regular smoking earlier in life (OR = 5.69, C_95% 2.3–13.8), reported more adverse family events (OR = 2.68; CI_95% 1.2–6.1), and had more parental SUD (OR = 5.36; CI_95% 1.0–14.5). Disability scores were significantly lower in SUD− and SUD^∧ groups compared to the SUD+ group.

Discussion

These findings suggest that ASD and ADHD share similar risk factors for SUD. High disability in ASD and ADHD with SUD may normalize after prolonged abstinence. Early onset of SUD was not associated with more severe disability scores than later onset. Results suggest that a subgroup of patients with former SUD may have a higher level of functioning before the onset of SUD in comparison to those without lifetime SUD.     

The prevalence and correlates of single cigarette selling among urban disadvantaged drug users in Baltimore,Maryland

Background

Selling of single cigarettes, also known as loosies, is a public health concern. Loosies allow for those with fewer resources to buy cigarettes without having to purchase a pack. Selling of loosies may cue smoking behaviors. In the US, socioeconomically disadvantaged populations have high rates of smoking and illicit drug use and the selling of loosies appears to be linked to the urban informal economy. We examined the proportion and frequency of cigarette selling and roles in the informal economy associated with selling loosies among a sample of urban drug users.

Methods

There were 801 participants, recruited by community outreach, assessed at baseline, who were enrolled in an HIV prevention intervention for drug users.

Results

Most (89%) smoked cigarettes in the prior 30 days, of whom 92% smoked daily. Self-reported selling of cigarettes was common with 58% reporting that they had sold cigarettes within the last six months; 20.4% reported selling cigarettes a few times a week and 7.4% reported daily selling of cigarettes. In a stepwise regression model, four sources of income were associated with frequent cigarette selling: providing street security (OR = 2.214, 95% CI 1.177–4.164), selling food stamps (OR = 1.461, 95% CI 1.003–2.126), pawning items (OR = 2.15, 95% CI 1.475–3.135), and selling drugs (OR = 1.634, 95% CI 1.008–2.648).

Conclusion

There is a high rate of selling loosies among urban substance users. The wide availability of loosies may promote smoking. Smoking cessation programs with drug treatment and economic development programs may help to reduce economic pressures to sell loosies.     

Internal mouthpiece designs as a future perspective for enhanced aerosol deposition. Comparative results for aerosol chemotherapy and aerosol antibiotics

Background

In an effort to identify factors producing a finest mist from Jet-Nebulizers we designed 2 mouthpieces with 4 different internal designs and 1–3 compartments.

Materials and methods

Ten different drugs previous used with their “ideal” combination of jet-nebulizer, residual-cup and loading were used. For each drug the mass median aerodynamic diameter size had been established along with their “ideal” combination.

Results

For both mouthpiece, drug was the most important factor due the high F-values (F_large = 251.7, p < 0.001 and F_small = 60.1, p < 0.001) produced. The design affected the droplet size but only for large mouthpiece (F_large = 5.99, p = 0.001, F_small = 1.72, p = 0.178). Cross designs create the smallest droplets (2.271) so differing from the other designs whose mean droplets were greater and equal ranging between 2.39 and 2.447. The number of compartments in the two devices regarding the 10 drugs was found not statistically significant (p-values 0.768 and 0.532 respectively). Interaction effects between drugs and design were statistically significant for both devices (F_large = 8.87, p < 0.001, F_small = 5.33, p < 0.001).

Conclusion

Based on our experiment we conclude that further improvement of the drugs intended for aerosol production is needed. In addition, the mouthpiece design and size play an important role in further enhancing the fine mist production and therefore further experimentation is needed.     

Injecting practices in sexual partnerships: Hepatitis C transmission potentials in a ‘risk equivalence’ framework

Background

Evidence indicates minimal hepatitis C (HCV) sexual transmission risk among HIV negative heterosexual partners. Limited HCV literacy has been demonstrated among people who inject drugs, yet there is a dearth of research exploring perceptions of HCV heterosexual transmission risk among this high risk population.

Methods

We conducted a qualitative life history study with people who had been injecting drugs for over six years, to explore the social practices and conditions of long-term HCV avoidance. Participants were recruited through London drug services and drug user networks. The sample comprised 10 women and 27 men (n = 37), of whom 22 were HCV antibody negative. Participants were aged from 23 to 57 years and had been injecting for 6 to 33 years. Twenty participants were in long term heterosexual partnerships.

Findings

The majority of participants in relationships reported ‘discriminate’ needle and syringe sharing with their primary sexual partner. Significantly, and in tension with biomedical evidence, participants commonly rationalised syringe sharing with sexual partners in terms of ‘risk equivalence’ with sexual practices in regard to HCV transmission. Participants’ uncertain knowledge regarding HCV transmission, coupled with unprotected sexual practices perceived as being normative were found to foster ‘risk equivalence’ beliefs and associated HCV transmission potential.

Conclusion

HCV prevention messages that ‘add on’ safe sex information can do more harm than good, perpetuating risk equivalence beliefs and an associated dismissal of safe injecting recommendations among those already practicing unprotected sex.     

Non-fatal overdose among adult prisoners with a history of injecting drug use in two Australian states

Background

Recently released prisoners are at markedly increased risk of death and drug-related causes predominate. Non-fatal overdose (NFOD) is considerably more common than fatal overdose, but has received relatively little research attention and most studies of NFOD in this population have suffered from small samples of unknown representativeness. This study aimed to estimate the prevalence and correlates of lifetime NFOD among prisoners in NSW and Queensland.

Methods

Cross-sectional surveys of adult prisoners in two Australian states: New South Wales (n = 972) and Queensland (n = 1316). Use of similar measures and methods in the two states made direct comparison of findings possible.

Results

In both NSW and Queensland, 23% of participants reported a lifetime history of NFOD and prisoners with a history of injecting drug use were significantly more likely to report lifetime NFOD. The lifetime prevalence of NFOD among prisoners with a history of injecting drug use was significantly higher in NSW than in Queensland (44% vs. 35%; p < 0.01). Independent correlates of lifetime NFOD were similar across the two states and included ever attempting suicide, ever injecting heroin, and ever injecting opioids.

Conclusions

The risk of NFOD among prisoners with a history of injecting drug use is high. An understanding of the risk factors for NFOD in this population can inform targeted, evidence-based interventions to reduce this risk.     

PTSD symptomatology and readiness to quit smoking among women with serious mental illness

Introduction

Posttraumatic stress disorder (PTSD) is a risk factor for tobacco addiction. The majority of research on PTSD and smoking has been conducted with men, particularly combat veterans, and little is known about the association among women. In a clinical sample of women civilian smokers with serious mental illness (SMI), we examined the prevalence of PTSD symptomatology and associations with physical and mental health functioning, co-occurring substance use, nicotine dependence, and readiness to quit smoking.

Methods

376 adult women smokers aged 18–73 were recruited from 7 acute inpatient psychiatry units and screened by diagnostic interview for current PTSD symptomatology (PTSD⁺). In multiple regressions, we examined the associations of screening PTSD⁺ with physical and mental health functioning; past-month drug use; past-year substance use disorders; nicotine dependence and readiness to quit smoking.

Results

Nearly half the sample (43%) screened PTSD⁺, which was significantly associated with the use of stimulants (OR = 1.26) and opiates (OR = 1.98), drug use disorders (OR = 2.01), and poorer mental health (B = − 2.78) but not physical health functioning. PTSD⁺ status was unrelated to nicotine dependence, but predicted greater desire to quit smoking (B = 2.13) and intention to stop smoking in the next month (OR = 2.21). In multivariate models that adjusted for substance use disorders, physical and mental health functioning, and nicotine dependence, screening PTSD⁺ remained predictive of greater desire and intention to quit smoking.

Conclusion

PTSD symptomatology was common in our sample of women smokers with SMI and associated with not only worse substance use and mental health, but also greater readiness to quit smoking, suggesting the need for and potential interest in integrative PTSD-addiction treatment among women.     

Randomized clinical trial examining duration of voucher-based reinforcement therapy for cocaine abstinence

Background

This is the first study to systematically manipulate duration of voucher-based reinforcement therapy (VBRT) to see if extending the duration increases abstinence during and following VBRT.

Methods

We randomized cocaine-dependent methadone-maintained adults to Standard (12 weeks; n = 62) or Extended (36 weeks; n = 68) VBRT and provided escalating voucher amounts contingent upon urinalysis verification of cocaine abstinence. Urinalysis was scheduled at least every 2 weeks during the 48-week study and more frequently during VBRT (3/week) and 12 weeks of Aftercare (2/week).

Results

Extended VBRT produced longer durations of continuous cocaine abstinence during weeks 1–24 (5.7 vs 2.7 weeks; p = 0.003) and proportionally more abstinence during weeks 24–36 (X² = 4.57, p = .03, OR = 2.18) compared to Standard VBRT. Duration of VBRT did not directly predict after-VBRT abstinence; but longer continuous abstinence during VBRT predicted abstinence during Aftercare (p = 0.001) and during the last 12 weeks of the study (p < 0.001). Extended VBRT averaged higher monthly voucher costs compared to Standard VBRT ($96 vs $43, p < .001); however, the average cost per week of abstinence attained was higher in the Standard group ($8.06 vs $5.88, p < .001). Participants in the Extended group with voucher costs exceeding $25 monthly averaged 20 weeks of continuous abstinence.

Conclusions

Greater abstinence occurred during Extended VBRT, but providing a longer duration was not by itself sufficient to maintain abstinence after VBRT. However, if abstinence can be captured and sustained during VBRT, then providing longer durations may help increase the continuous abstinence that predicts better long-term outcomes.     

Atypical neural activity during inhibitory processing in substance-naïve youth who later experience alcohol-induced blackouts

Background

Alcohol-induced blackouts are associated with the development of alcohol abuse and dependence, so it is important to consider potential neurobiological risk factors for experiencing this problem prior to the onset of substance use. This study examines whether neural activity during inhibitory processing might be atypical in substance-naïve youth who later experience alcohol-induced blackouts.

Methods

We examined inhibitory processing during fMRI with a go/no-go task that requires withholding a prepotent response in substance-naïve youth who would later transition into heavy drinking (n = 40) and youth who remain abstinent (n = 20). After approximately 5 years of annual follow-up assessments, youth were classified as nondrinkers (n = 20), and heavy drinking youth were classified as having experienced an alcohol-induced blackout (blackout+; n = 20) or not (blackout−; n = 20). Groups were matched on demographic variables, and youth who experienced blackouts were matched on follow-up substance use.

Results

Prior to initiating substance use, blackout+ youth showed greater activation during inhibitory processing than nondrinkers and blackout− youth in frontal and cerebellar brain regions. Mean activation during correct inhibitory responses relative to go responses in the left and right middle frontal gyri at baseline predicted future blackout experience, after controlling for follow-up externalizing behaviors and lifetime alcohol consumption.

Conclusions

Substance-naïve adolescents who later experience alcohol-induced blackouts show increased neural effort during inhibitory processing, as compared to adolescents who go on to drink at similar levels but do not experience blackouts and healthy, nondrinking controls, suggesting a neurobiological vulnerability to alcohol-induced memory impairments.     

The aftermath of public housing relocation: Relationship to substance misuse

Introduction

Several cross-sectional studies have examined relationships between neighborhood characteristics and substance misuse. Using data from a sample of African-American adults relocating from US public housing complexes, we examined relationships between changes in exposure to local socioeconomic conditions and substance misuse over time. We tested the hypothesis that adults who experienced greater post-relocation improvements in local economic conditions and social disorder would have a lower probability of recent substance misuse.

Methods

Data were drawn from administrative sources to describe the census tracts where participants lived before and after relocating. Data on individual-level characteristics, including binge drinking, illicit drug use, and substance dependence, were gathered via survey before and after the relocations. Multilevel models were used to test hypotheses.

Results

Participants (N = 172) experienced improvements in tract-level economic conditions and, to a lesser degree, in social disorder after moving. A one standard-deviation improvement in tract-level economic conditions was associated with a decrease in recent binge drinking from 34% to 20% (p = 0.04) and with a decline in using illicit drugs weekly or more from 37% to 16% (p = 0.02). A reduction in tract-level alcohol outlet density of >3.0 outlets per square mile predicted a reduction in binge drinking from 32% to 18% at p = 0.05 significance level.

Discussion

We observed relationships between improvements in tract-level conditions and declines in substance misuse, providing further support for the importance of the local environment in shaping substance misuse. These findings have important implications for public housing policies and future research.