Matthew Worley | University of California, San Diego (original) (raw)
Papers by Matthew Worley
Drug and alcohol dependence, 2015
Research grounded in behavioral economics has previously linked addictive behavior to disrupted d... more Research grounded in behavioral economics has previously linked addictive behavior to disrupted decision-making and reward-processing, but these principles have not been examined in prescription opioid addiction, which is currently a major public health problem. This study examined whether pre-treatment drug reinforcement value predicted opioid use during outpatient treatment of prescription opioid addiction. Secondary analyses examined participants with prescription opioid dependence who received 12 weeks of buprenorphine-naloxone and counseling in a multi-site clinical trial (N=353). Baseline measures assessed opioid source and indices of drug reinforcement value, including the total amount and proportion of income spent on drugs. Weekly urine drug screens measured opioid use. Obtaining opioids from doctors was associated with lower pre-treatment drug spending, while obtaining opioids from dealers/patients was associated with greater spending. Controlling for demographics, opioid ...
Alcoholism, clinical and experimental research, 2015
Oral naltrexone is an efficacious medication for treatment of alcohol dependence, but small effec... more Oral naltrexone is an efficacious medication for treatment of alcohol dependence, but small effect sizes and variability in outcomes suggest the presence of person-level moderators of naltrexone response. Identification of contextual or psychosocial moderators may assist in guiding clinical recommendations. Given the established importance of social networks in drinking outcomes, as well as the potential effects of naltrexone in reducing cue reactivity which may be especially important among those with more heavy drinkers and more alcohol cues in their networks, we examined pretreatment social network variables as potential moderators of naltrexone treatment effects in the COMBINE study. The sample included all COMBINE study participants in medication conditions with full data on the Important People Inventory (IPI) and covariates at intake (N = 1,197). The intake IPI assessed whether participants had any frequent drinkers in their network and the average frequency of contact with t...
Drug and Alcohol Dependence, 2015
This study explored whether the density of family history (FH) of substance use disorders relates... more This study explored whether the density of family history (FH) of substance use disorders relates to post-treatment substance use outcomes in adolescents, with the primary aim of determining whether FH exerts a relatively stronger influence on longer-term outcomes. The present investigation examined adolescents (ages 12-18, n=366) from two independent samples who were treated for alcohol/substance use disorder (ASUD) and re-assessed during the eight years following treatment with identical methodology. Primary substance use outcomes were assessed at 1, 2, 4, 6, and 8 years post-treatment and included total drinks, days using marijuana, and days using other drugs. In hierarchical linear models there were significant FH density×linear time interactions for total drinks (z=12.75, p<0.001) and marijuana use days (z=4.39, p<0.001); greater FH density predicted more total drinks and more marijuana use days, with both associations becoming stronger over time. The increasing linkage between FH and other drug use was not significant over time. Findings are consistent with previous research indicating that the risk associated with FH increases over time, especially in relation to quantity/frequency measures of alcohol and marijuana use. By extending these findings to an adolescent clinical sample, the current study highlights that FH density of alcohol and drug dependence is a risk factor for poorer long-term outcomes for adolescent-onset ASUD youth as they transition into adulthood. Future work should explore the mechanisms underlying greater post-treatment substance use for adolescents/young adults with greater FH density.
Vaccine, 2014
We have established that the efficacy of a heterologous poxvirus vectored HIV vaccine, fowlpox vi... more We have established that the efficacy of a heterologous poxvirus vectored HIV vaccine, fowlpox virus (FPV)-HIV gag/pol prime followed by attenuated vaccinia virus (VV)-HIV gag/pol booster immunisation, is strongly influenced by the cytokine milieu at the priming vaccination site, with endogenous IL-13 detrimental to the quality of the HIV specific CD8+ T cell response induced. We have now developed a novel HIV vaccine that co-expresses a C-terminal deletion mutant of the mouse IL-4, deleted for the essential tyrosine (Y119) required for signalling. In our vaccine system, the mutant IL-4C118 can bind to IL-4 type I and II receptors with high affinity, and transiently prevent the signalling of both IL-4 and IL-13 at the vaccination site. When this IL-4C118 adjuvanted vaccine was used in an intranasal rFPV/intramuscular rVV prime-boost immunisation strategy, greatly enhanced mucosal/systemic HIV specific CD8+ T cells with higher functional avidity, expressing IFN-γ, TNF-α and IL-2 and greater protective efficacy were detected. Surprisingly, the IL-4C118 adjuvanted vaccines also induced robust long-lived HIV gag-specific serum antibody responses, specifically IgG1 and IgG2a. The p55-gag IgG2a responses induced were of a higher magnitude relative to the IL-13Rα2 adjuvant vaccine. More interestingly, our recently tested IL-13Rα2 adjuvanted vaccine which only inhibited IL-13 activity, even though induced excellent high avidity HIV-specific CD8+ T cells, had a detrimental impact on the induction of gag-specific IgG2a antibody immunity. Our observations suggest that (i) IL-4 cell-signalling in the absence of IL-13 retarded gag-specific antibody isotype class switching, or (ii) IL-13Rα2 signalling was involved in inducing good gag-specific B cell immunity. Thus, we believe our novel IL-4R antagonist adjuvant strategy offers great promise not only for HIV-1 vaccines, but also against a range of chronic infections where sustained high quality mucosal and systemic T and B cell immunity are required for protection.
Suicide and Life-Threatening Behavior, 2011
This study examined whether widely accepted suicide risk factors are useful in predicting suicide... more This study examined whether widely accepted suicide risk factors are useful in predicting suicide-related hospitalization, beyond history of a suicide attempt, in high-risk treatment-seeking veterans with depression and substance dependence. Negative mood regulation expectancies were the only significant predictor of hospitalization during 6-months of outpatient treatment. History of a suicide attempt was the only significant predictor of hospitalization during the one-year follow-up period. Results suggest that within high-risk populations, standard suicide risk factors may not identify individuals who will engage in suicidal behaviors resulting in hospitalization. Assessing negative mood regulation expectations may assist in identifying those most at risk.
Substance Use & Misuse, 2013
In 2008-2009, we conducted a 6-week, open-label trial of transdermal nicotine replacement therapy... more In 2008-2009, we conducted a 6-week, open-label trial of transdermal nicotine replacement therapy and practical counseling for 34 adolescents seeking smoking cessation in Los Angeles. Dependent outcomes were study retention, use of the patch, and 7-day quit status at the end-of-study and at follow-up visits. Predictors of outcomes included cigarette dependence, withdrawal symptoms, demographic and psychiatric measures, and other substance use. Variables significant in bivariate analysis (p < .10) were retained in a multivariate model. Subjects had significant pre-to-post reductions in quit rates, dependence, and withdrawal symptoms. Subjects also reported a high number of comorbidities. Implications for clinicians are discussed.
Substance Abuse, 2013
Among substance-dependent individuals, comorbid major depressive disorder (MDD) is associated wit... more Among substance-dependent individuals, comorbid major depressive disorder (MDD) is associated with greater severity and poorer treatment outcomes, but little research has examined mediators of posttreatment substance use outcomes within this population. Using latent growth curve models, the authors tested relationships between individual rates of change in 12-step involvement and substance use, utilizing posttreatment follow-up data from a trial of group Twelve-Step Facilitation (TSF) and integrated cognitive-behavioral therapy (ICBT) for veterans with substance dependence and MDD. Although TSF patients were higher on 12-step affiliation and meeting attendance at end-of-treatment as compared with ICBT, they also experienced significantly greater reductions in these variables during the year following treatment, ending at similar levels as ICBT. Veterans in TSF also had significantly greater increases in drinking frequency during follow-up, and this group difference was mediated by their greater reductions in 12-step affiliation and meeting attendance. Patients with comorbid depression appear to have difficulty sustaining high levels of 12-step involvement after the conclusion of formal 12-step interventions, which predicts poorer drinking outcomes over time. Modifications to TSF and other formal 12-step protocols or continued therapeutic contact may be necessary to sustain 12-step involvement and reduced drinking for patients with substance dependence and MDD.
Psychotherapy Research, 2007
Psychoanalytic Psychology, 2008
Journal of Substance Abuse Treatment, 2010
Patients with comorbid substance use disorder (SUD) and depression incur greater treatment costs ... more Patients with comorbid substance use disorder (SUD) and depression incur greater treatment costs than those with either disorder alone. Integrated treatment targeting both issues concurrently has been shown to reduce substance use and depression in this population, but little is known about the effects of such treatment on the utilization of costly health services. This study compared 18-month patterns of service utilization for 236 veterans with comorbid SUD depression randomly assigned to 6 months of either Integrated Cognitive Behavioral Therapy (ICBT) or Twelve-Step Facilitation Therapy. Treatment group differences were found for the utilization of psychotropic medication services and inpatient hospitalization. Higher rates of therapy attendance, lower baseline depression, and receiving ICBT all predicted shorter admissions for those hospitalized during treatment. Ethnicity and gender predicted medication service use both during and following treatment. The findings provide evidence supporting the long-term cost-effectiveness of integrated treatment for this high-risk population.
Journal of Substance Abuse Treatment, 2012
This study examined the longitudinal association between substance use and depressive symptoms in... more This study examined the longitudinal association between substance use and depressive symptoms in veterans receiving outpatient treatment for comorbid substance use disorder and major depression. Veterans (N = 237, mean age = 48.2 years, 90% male, 70% Caucasian) received either 6 months of group integrated cognitive-behavioral therapy or twelve-step facilitation. Hamilton Depression Rating Scale scores and percent days using any substance were assessed every 3 months up to 1 year posttreatment. Greater substance use predicted time-varying elevations in depression above individual patterns of change in depression. Moreover, change in depressive symptoms was associated with change in both the likelihood of any substance use and the frequency of use during the treatment and follow-up periods. Changes in these symptoms appear to be linked, such that individuals with greater reductions in substance use have greater reductions in depressive symptoms (and vice versa).
Journal of Substance Abuse Treatment, 2007
We report here on the feasibility of implementing a semiautomated performance improvement system-... more We report here on the feasibility of implementing a semiautomated performance improvement system-Patient Feedback (PF)-that enables real-time monitoring of patient ratings of therapeutic alliance, treatment satisfaction, and drug/alcohol use in outpatient substance abuse treatment clinics. The study was conducted in six clinics within the National Institute on Drug Abuse Clinical Trials Network. It involved a total of 39 clinicians and 6 clinic supervisors. Throughout the course of the study (consisting of five phases: training period [4 6weeks], baseline [4 weeks], intervention [12 weeks], postintervention assessment [4 weeks], sustainability [1 year]), there was an overall collection rate of 75.5% of the clinic patient census. In general, the clinicians in these clinics had very positive treatment satisfaction and alliance ratings throughout the study. However, one clinic had worse drug use scores at baseline than other participating clinics and showed a decrease in self-reported drug use at postintervention. Although the implementation of the PF system proved to be feasible in actual clinical settings, further modifications of the PF system are needed to enhance any potential clinical usefulness. D 2007 Elsevier Inc. All rights reserved.
Journal of Consulting and Clinical Psychology, 2014
Neurocognitive impairment has not consistently predicted substance use treatment outcomes but has... more Neurocognitive impairment has not consistently predicted substance use treatment outcomes but has been linked to proximal mediators of outcome. These indirect effects have not been examined in adults with substance dependence and co-occurring psychiatric disorders. We examined mediators and moderators of the effects of neurocognitive impairment on substance use among adults in treatment for alcohol or drug dependence and major depression (MDD). Participants were veterans (N = 197, mean age = 49.3 years, 90% male, 75% Caucasian) in a trial of 2 group interventions for alcohol/drug dependence and MDD. Measures examined here included intake neurocognitive assessments and percent days drinking (PDD), percent days using drugs (PDDRG), self-efficacy, 12-step affiliation, and depressive symptoms measured every 3 months from intake to the 18-month follow-up. Greater intake neurocognitive impairment predicted lower self-efficacy, lower 12-step affiliation, and greater depression severity, and these time-varying variables mediated the effects of impairment on future PDD and PDDRG. The prospective effects of 12-step affiliation on future PDD were greater for those with greater neurocognitive impairment. Impairment also interacted with depression to moderate the effects of 12-step affiliation and self-efficacy on PDD. Adults with greater impairment and currently severe depression had the strongest associations between 12-step affiliation/self-efficacy and future drinking. Greater neurocognitive impairment may lead to poorer outcomes from group therapy for alcohol/drug dependence and MDD due to compromised change in therapeutic processes. Distal factors such as neurocognitive impairment can interact with dynamic risk factors to modulate the association between therapeutic processes and future drinking outcomes.
American Journal on Addictions, 2008
Addiction, 2012
Among patients with substance dependence and comorbid major depressive disorder (MDD) receiving t... more Among patients with substance dependence and comorbid major depressive disorder (MDD) receiving treatment in a controlled trial, we examined if group differences in depression were mediated by 12-Step involvement, and if the effects of 12-Step involvement on future alcohol and drug use were mediated by reductions in depression. Controlled trial of Twelve-Step facilitation (TSF) and integrated cognitive-behavioral therapy (ICBT), delivered in out-patient groups for 6 months with adjunct pharmacotherapy. Out-patient dual diagnosis clinic in Veteran's Affairs Healthcare Center. Veterans (n = 209) diagnosed with alcohol, stimulant or marijuana dependence and substance-independent MDD. Twelve-Step attendance and affiliation, depression severity, percentage of days drinking and percentage of days using drugs assessed at baseline and months 3, 6 and 9. In multi-level analyses greater 12-Step meeting attendance predicted lower depression and mediated the superior depression outcomes of the TSF group, explaining 24.3% of the group difference in depression. Independent of treatment group, lower depression severity predicted lower future alcohol use and mediated the effects of 12-Step meetings, explaining 15.7% of their effects on future drinking. Controlled, lagged models indicated these effects were not confounded by current substance use, suggesting that depression had unique associations with 12-Step meeting attendance and future drinking. For patients with substance dependence and major depressive disorder, attendance at 12-Step meetings is associated with mental health benefits that extend beyond substance use, and reduced depression could be a key mechanism whereby 12-Step meetings reduce future drinking in this population.
Drug and alcohol dependence, 2015
Research grounded in behavioral economics has previously linked addictive behavior to disrupted d... more Research grounded in behavioral economics has previously linked addictive behavior to disrupted decision-making and reward-processing, but these principles have not been examined in prescription opioid addiction, which is currently a major public health problem. This study examined whether pre-treatment drug reinforcement value predicted opioid use during outpatient treatment of prescription opioid addiction. Secondary analyses examined participants with prescription opioid dependence who received 12 weeks of buprenorphine-naloxone and counseling in a multi-site clinical trial (N=353). Baseline measures assessed opioid source and indices of drug reinforcement value, including the total amount and proportion of income spent on drugs. Weekly urine drug screens measured opioid use. Obtaining opioids from doctors was associated with lower pre-treatment drug spending, while obtaining opioids from dealers/patients was associated with greater spending. Controlling for demographics, opioid ...
Alcoholism, clinical and experimental research, 2015
Oral naltrexone is an efficacious medication for treatment of alcohol dependence, but small effec... more Oral naltrexone is an efficacious medication for treatment of alcohol dependence, but small effect sizes and variability in outcomes suggest the presence of person-level moderators of naltrexone response. Identification of contextual or psychosocial moderators may assist in guiding clinical recommendations. Given the established importance of social networks in drinking outcomes, as well as the potential effects of naltrexone in reducing cue reactivity which may be especially important among those with more heavy drinkers and more alcohol cues in their networks, we examined pretreatment social network variables as potential moderators of naltrexone treatment effects in the COMBINE study. The sample included all COMBINE study participants in medication conditions with full data on the Important People Inventory (IPI) and covariates at intake (N = 1,197). The intake IPI assessed whether participants had any frequent drinkers in their network and the average frequency of contact with t...
Drug and Alcohol Dependence, 2015
This study explored whether the density of family history (FH) of substance use disorders relates... more This study explored whether the density of family history (FH) of substance use disorders relates to post-treatment substance use outcomes in adolescents, with the primary aim of determining whether FH exerts a relatively stronger influence on longer-term outcomes. The present investigation examined adolescents (ages 12-18, n=366) from two independent samples who were treated for alcohol/substance use disorder (ASUD) and re-assessed during the eight years following treatment with identical methodology. Primary substance use outcomes were assessed at 1, 2, 4, 6, and 8 years post-treatment and included total drinks, days using marijuana, and days using other drugs. In hierarchical linear models there were significant FH density×linear time interactions for total drinks (z=12.75, p<0.001) and marijuana use days (z=4.39, p<0.001); greater FH density predicted more total drinks and more marijuana use days, with both associations becoming stronger over time. The increasing linkage between FH and other drug use was not significant over time. Findings are consistent with previous research indicating that the risk associated with FH increases over time, especially in relation to quantity/frequency measures of alcohol and marijuana use. By extending these findings to an adolescent clinical sample, the current study highlights that FH density of alcohol and drug dependence is a risk factor for poorer long-term outcomes for adolescent-onset ASUD youth as they transition into adulthood. Future work should explore the mechanisms underlying greater post-treatment substance use for adolescents/young adults with greater FH density.
Vaccine, 2014
We have established that the efficacy of a heterologous poxvirus vectored HIV vaccine, fowlpox vi... more We have established that the efficacy of a heterologous poxvirus vectored HIV vaccine, fowlpox virus (FPV)-HIV gag/pol prime followed by attenuated vaccinia virus (VV)-HIV gag/pol booster immunisation, is strongly influenced by the cytokine milieu at the priming vaccination site, with endogenous IL-13 detrimental to the quality of the HIV specific CD8+ T cell response induced. We have now developed a novel HIV vaccine that co-expresses a C-terminal deletion mutant of the mouse IL-4, deleted for the essential tyrosine (Y119) required for signalling. In our vaccine system, the mutant IL-4C118 can bind to IL-4 type I and II receptors with high affinity, and transiently prevent the signalling of both IL-4 and IL-13 at the vaccination site. When this IL-4C118 adjuvanted vaccine was used in an intranasal rFPV/intramuscular rVV prime-boost immunisation strategy, greatly enhanced mucosal/systemic HIV specific CD8+ T cells with higher functional avidity, expressing IFN-γ, TNF-α and IL-2 and greater protective efficacy were detected. Surprisingly, the IL-4C118 adjuvanted vaccines also induced robust long-lived HIV gag-specific serum antibody responses, specifically IgG1 and IgG2a. The p55-gag IgG2a responses induced were of a higher magnitude relative to the IL-13Rα2 adjuvant vaccine. More interestingly, our recently tested IL-13Rα2 adjuvanted vaccine which only inhibited IL-13 activity, even though induced excellent high avidity HIV-specific CD8+ T cells, had a detrimental impact on the induction of gag-specific IgG2a antibody immunity. Our observations suggest that (i) IL-4 cell-signalling in the absence of IL-13 retarded gag-specific antibody isotype class switching, or (ii) IL-13Rα2 signalling was involved in inducing good gag-specific B cell immunity. Thus, we believe our novel IL-4R antagonist adjuvant strategy offers great promise not only for HIV-1 vaccines, but also against a range of chronic infections where sustained high quality mucosal and systemic T and B cell immunity are required for protection.
Suicide and Life-Threatening Behavior, 2011
This study examined whether widely accepted suicide risk factors are useful in predicting suicide... more This study examined whether widely accepted suicide risk factors are useful in predicting suicide-related hospitalization, beyond history of a suicide attempt, in high-risk treatment-seeking veterans with depression and substance dependence. Negative mood regulation expectancies were the only significant predictor of hospitalization during 6-months of outpatient treatment. History of a suicide attempt was the only significant predictor of hospitalization during the one-year follow-up period. Results suggest that within high-risk populations, standard suicide risk factors may not identify individuals who will engage in suicidal behaviors resulting in hospitalization. Assessing negative mood regulation expectations may assist in identifying those most at risk.
Substance Use & Misuse, 2013
In 2008-2009, we conducted a 6-week, open-label trial of transdermal nicotine replacement therapy... more In 2008-2009, we conducted a 6-week, open-label trial of transdermal nicotine replacement therapy and practical counseling for 34 adolescents seeking smoking cessation in Los Angeles. Dependent outcomes were study retention, use of the patch, and 7-day quit status at the end-of-study and at follow-up visits. Predictors of outcomes included cigarette dependence, withdrawal symptoms, demographic and psychiatric measures, and other substance use. Variables significant in bivariate analysis (p < .10) were retained in a multivariate model. Subjects had significant pre-to-post reductions in quit rates, dependence, and withdrawal symptoms. Subjects also reported a high number of comorbidities. Implications for clinicians are discussed.
Substance Abuse, 2013
Among substance-dependent individuals, comorbid major depressive disorder (MDD) is associated wit... more Among substance-dependent individuals, comorbid major depressive disorder (MDD) is associated with greater severity and poorer treatment outcomes, but little research has examined mediators of posttreatment substance use outcomes within this population. Using latent growth curve models, the authors tested relationships between individual rates of change in 12-step involvement and substance use, utilizing posttreatment follow-up data from a trial of group Twelve-Step Facilitation (TSF) and integrated cognitive-behavioral therapy (ICBT) for veterans with substance dependence and MDD. Although TSF patients were higher on 12-step affiliation and meeting attendance at end-of-treatment as compared with ICBT, they also experienced significantly greater reductions in these variables during the year following treatment, ending at similar levels as ICBT. Veterans in TSF also had significantly greater increases in drinking frequency during follow-up, and this group difference was mediated by their greater reductions in 12-step affiliation and meeting attendance. Patients with comorbid depression appear to have difficulty sustaining high levels of 12-step involvement after the conclusion of formal 12-step interventions, which predicts poorer drinking outcomes over time. Modifications to TSF and other formal 12-step protocols or continued therapeutic contact may be necessary to sustain 12-step involvement and reduced drinking for patients with substance dependence and MDD.
Psychotherapy Research, 2007
Psychoanalytic Psychology, 2008
Journal of Substance Abuse Treatment, 2010
Patients with comorbid substance use disorder (SUD) and depression incur greater treatment costs ... more Patients with comorbid substance use disorder (SUD) and depression incur greater treatment costs than those with either disorder alone. Integrated treatment targeting both issues concurrently has been shown to reduce substance use and depression in this population, but little is known about the effects of such treatment on the utilization of costly health services. This study compared 18-month patterns of service utilization for 236 veterans with comorbid SUD depression randomly assigned to 6 months of either Integrated Cognitive Behavioral Therapy (ICBT) or Twelve-Step Facilitation Therapy. Treatment group differences were found for the utilization of psychotropic medication services and inpatient hospitalization. Higher rates of therapy attendance, lower baseline depression, and receiving ICBT all predicted shorter admissions for those hospitalized during treatment. Ethnicity and gender predicted medication service use both during and following treatment. The findings provide evidence supporting the long-term cost-effectiveness of integrated treatment for this high-risk population.
Journal of Substance Abuse Treatment, 2012
This study examined the longitudinal association between substance use and depressive symptoms in... more This study examined the longitudinal association between substance use and depressive symptoms in veterans receiving outpatient treatment for comorbid substance use disorder and major depression. Veterans (N = 237, mean age = 48.2 years, 90% male, 70% Caucasian) received either 6 months of group integrated cognitive-behavioral therapy or twelve-step facilitation. Hamilton Depression Rating Scale scores and percent days using any substance were assessed every 3 months up to 1 year posttreatment. Greater substance use predicted time-varying elevations in depression above individual patterns of change in depression. Moreover, change in depressive symptoms was associated with change in both the likelihood of any substance use and the frequency of use during the treatment and follow-up periods. Changes in these symptoms appear to be linked, such that individuals with greater reductions in substance use have greater reductions in depressive symptoms (and vice versa).
Journal of Substance Abuse Treatment, 2007
We report here on the feasibility of implementing a semiautomated performance improvement system-... more We report here on the feasibility of implementing a semiautomated performance improvement system-Patient Feedback (PF)-that enables real-time monitoring of patient ratings of therapeutic alliance, treatment satisfaction, and drug/alcohol use in outpatient substance abuse treatment clinics. The study was conducted in six clinics within the National Institute on Drug Abuse Clinical Trials Network. It involved a total of 39 clinicians and 6 clinic supervisors. Throughout the course of the study (consisting of five phases: training period [4 6weeks], baseline [4 weeks], intervention [12 weeks], postintervention assessment [4 weeks], sustainability [1 year]), there was an overall collection rate of 75.5% of the clinic patient census. In general, the clinicians in these clinics had very positive treatment satisfaction and alliance ratings throughout the study. However, one clinic had worse drug use scores at baseline than other participating clinics and showed a decrease in self-reported drug use at postintervention. Although the implementation of the PF system proved to be feasible in actual clinical settings, further modifications of the PF system are needed to enhance any potential clinical usefulness. D 2007 Elsevier Inc. All rights reserved.
Journal of Consulting and Clinical Psychology, 2014
Neurocognitive impairment has not consistently predicted substance use treatment outcomes but has... more Neurocognitive impairment has not consistently predicted substance use treatment outcomes but has been linked to proximal mediators of outcome. These indirect effects have not been examined in adults with substance dependence and co-occurring psychiatric disorders. We examined mediators and moderators of the effects of neurocognitive impairment on substance use among adults in treatment for alcohol or drug dependence and major depression (MDD). Participants were veterans (N = 197, mean age = 49.3 years, 90% male, 75% Caucasian) in a trial of 2 group interventions for alcohol/drug dependence and MDD. Measures examined here included intake neurocognitive assessments and percent days drinking (PDD), percent days using drugs (PDDRG), self-efficacy, 12-step affiliation, and depressive symptoms measured every 3 months from intake to the 18-month follow-up. Greater intake neurocognitive impairment predicted lower self-efficacy, lower 12-step affiliation, and greater depression severity, and these time-varying variables mediated the effects of impairment on future PDD and PDDRG. The prospective effects of 12-step affiliation on future PDD were greater for those with greater neurocognitive impairment. Impairment also interacted with depression to moderate the effects of 12-step affiliation and self-efficacy on PDD. Adults with greater impairment and currently severe depression had the strongest associations between 12-step affiliation/self-efficacy and future drinking. Greater neurocognitive impairment may lead to poorer outcomes from group therapy for alcohol/drug dependence and MDD due to compromised change in therapeutic processes. Distal factors such as neurocognitive impairment can interact with dynamic risk factors to modulate the association between therapeutic processes and future drinking outcomes.
American Journal on Addictions, 2008
Addiction, 2012
Among patients with substance dependence and comorbid major depressive disorder (MDD) receiving t... more Among patients with substance dependence and comorbid major depressive disorder (MDD) receiving treatment in a controlled trial, we examined if group differences in depression were mediated by 12-Step involvement, and if the effects of 12-Step involvement on future alcohol and drug use were mediated by reductions in depression. Controlled trial of Twelve-Step facilitation (TSF) and integrated cognitive-behavioral therapy (ICBT), delivered in out-patient groups for 6 months with adjunct pharmacotherapy. Out-patient dual diagnosis clinic in Veteran's Affairs Healthcare Center. Veterans (n = 209) diagnosed with alcohol, stimulant or marijuana dependence and substance-independent MDD. Twelve-Step attendance and affiliation, depression severity, percentage of days drinking and percentage of days using drugs assessed at baseline and months 3, 6 and 9. In multi-level analyses greater 12-Step meeting attendance predicted lower depression and mediated the superior depression outcomes of the TSF group, explaining 24.3% of the group difference in depression. Independent of treatment group, lower depression severity predicted lower future alcohol use and mediated the effects of 12-Step meetings, explaining 15.7% of their effects on future drinking. Controlled, lagged models indicated these effects were not confounded by current substance use, suggesting that depression had unique associations with 12-Step meeting attendance and future drinking. For patients with substance dependence and major depressive disorder, attendance at 12-Step meetings is associated with mental health benefits that extend beyond substance use, and reduced depression could be a key mechanism whereby 12-Step meetings reduce future drinking in this population.