Evaluating treatments for posttraumatic stress disorder, alcohol and other drug use disorders using meta-analysis of individual patient data: Design and methodology of a virtual clinical trial

State of the Science: Treatment of comorbid posttraumatic stress disorder and substance use disorders

Posttraumatic stress disorder (PTSD) and substance use disorders (SUDs) co-occur at high rates, with research showing that up to nearly 60% of individuals with PTSD also suffer from an alcohol and/or drug use disorder. PTSD/SUD is complex; associated with adverse health, social, and economic outcomes; and can be challenging to treat. Over the past decade, the landscape of treatment research addressing PTSD/SUD has significantly expanded. Ongoing efforts aimed at developing and evaluating novel treatments for PTSD/SUD, encompassing both psychotherapy and pharmacotherapy approaches, are steadily advancing. As such, this State of the Science paper reviews the literature on the latest scientific advances in treating PTSD/SUD. Clinical practice guidelines for the treatment of PTSD/SUD are discussed, along with evidence-based psychotherapies and emerging interventions. Rigorously conducted clinical trials demonstrate that individual, manualized, trauma-focused treatments are the most efficacious psychotherapies to use among individuals with PTSD/SUD. Moreover, patients do not need to be abstinent to initiate or benefit from evidence-based PTSD treatment. To date, no medications have been established for this comorbidity. We highlight ongoing research on novel treatments for PTSD/SUD, such as new forms of integrated trauma-focused psychotherapies, pharmacological augmentation strategies, and technology-based enhancements. Finally, promising future directions for the field are discussed.

Cannabis use and trauma-focused treatment for co-occurring posttraumatic stress disorder and substance use disorders: A meta-analysis of individual patient data

High rates of cannabis use among people with posttraumatic stress disorder (PTSD) have raised questions about the efficacy of evidence-based PTSD treatments for individuals reporting cannabis use, particularly those with co-occurring alcohol or other substance use disorders (SUDs). Using a subset of four randomized clinical trials (RCTs) included in Project Harmony, an individual patient meta-analysis of 36 RCTs (total N = 4046) of treatments for co-occurring PTSD+SUD, we examined differences in trauma-focused (TF) and non-trauma-focused (non-TF) treatment outcomes for individuals who did and did not endorse baseline cannabis use (N = 410; 70% male; 33.2% endorsed cannabis use). Propensity score-weighted mixed effects modeling evaluated main and interactive effects of treatment assignment (TF versus non-TF) and baseline cannabis use (yes/no) on attendance rates and within-treatment changes in PTSD, alcohol, and non-cannabis drug use severity. Results revealed significant improvements across outcomes among participants in all conditions, with larger PTSD symptom reductions but lower attendance among individuals receiving TF versus non-TF treatment in both cannabis groups. Participants achieved similar reductions in alcohol and drug use across all conditions. TF outperformed non-TF treatments regardless of recent cannabis use, underscoring the importance of reducing barriers to accessing TF treatments for individuals reporting cannabis use.

Introduction to the Special Issue on Innovations and Applications of Integrative Data Analysis (IDA) and Related Data Harmonization Procedures in Prevention Science

This paper serves as an introduction to the special issue of Prevention Science entitled, "Innovations and Applications of Integrative Data Analysis (IDA) and Related Data Harmonization Procedures in Prevention Science." This special issue includes a collection of original papers from multiple disciplines that apply individual-level data synthesis methodologies, including IDA, individual participant meta-analysis, and other related methods to harmonize and integrate multiple datasets from intervention trials of the same or similar interventions. This work builds on a series of papers appearing in a prior Prevention Science special issue, entitled "Who Benefits from Programs to Prevent Adolescent Depression?" (Howe, Pantin, & Perrino, 2018). Since the publication of this prior work, the use of individual-level data synthesis has increased considerably in and outside of prevention. As such, there is a need for an update on current and future directions in IDA, with careful consideration of innovations and applications of these methods to fill important research gaps in prevention science. The papers in this issue are organized into two broad categories of (1) evidence synthesis papers that apply best practices in data harmonization and individual-level data synthesis and (2) new and emerging design, psychometric, and methodological issues and solutions. This collection of original papers is followed by two invited commentaries which provide insight and important reflections on the field and future directions for prevention science.

Mitigating Multiple Sources of Bias in a Quasi-Experimental Integrative Data Analysis: Does Treating Childhood Anxiety Prevent Substance Use Disorders in Late Adolescence/Young Adulthood?

Psychiatric epidemiologists, developmental psychopathologists, prevention scientists, and treatment researchers have long speculated that treating child anxiety disorders could prevent alcohol and other drug use disorders in young adulthood. A primary challenge in examining long-term effects of anxiety disorder treatment from randomized controlled trials is that all participants receive an immediate or delayed study-related treatment prior to long-term follow-up assessment. Thus, if a long-term follow-up is conducted, a comparison condition no longer exists within the trial. Quasi-experimental designs (QEDs) pairing such clinical samples with comparable untreated epidemiological samples offer a method of addressing this challenge. Selection bias, often a concern in QEDs, can be mitigated by propensity score weighting. A second challenge may arise because the clinical and epidemiological studies may not have used identical measures, necessitating Integrative Data Analysis (IDA) for measure harmonization and scale score estimation. The present study uses a combination of propensity score weighting, zero-inflated mixture moderated nonlinear factor analysis (ZIM-MNLFA), and potential outcomes mediation in a child anxiety treatment QED/IDA (n = 396). Under propensity score-weighted potential outcomes mediation, CBT led to reductions in substance use disorder severity, the effects of which were mediated by reductions in anxiety severity in young adulthood. Sensitivity analyses highlighted the importance of attending to multiple types of bias. This study illustrates how hybrid QED/IDAs can be used in secondary prevention contexts for improved measurement and causal inference, particularly when control participants in clinical trials receive study-related treatment prior to long-term assessment.

Methodological Strategies for Prospective Harmonization of Studies: Application to 10 Distinct Outcomes Studies of Preventive Interventions Targeting Opioid Misuse

The Helping to End Addiction Long-Term (HEAL) Prevention Cooperative (HPC) is rapidly developing 10 distinct evidence-based interventions for implementation in a variety of settings to prevent opioid misuse and opioid use disorder. One HPC objective is to compare intervention impacts on opioid misuse initiation, escalation, severity, and disorder and identify whether any HPC interventions are more effective than others for types of individuals. It provides a rare opportunity to prospectively harmonize measures across distinct outcomes studies. This paper describes the needs, opportunities, strategies, and processes that were used to harmonize HPC data. They are illustrated with a strategy to measure opioid use that spans the spectrum of opioid use experiences (termed involvement) and is composed of common "anchor items" ranging from initiation to symptoms of opioid use disorder. The limitations and opportunities anticipated from this approach to data harmonization are reviewed. Lastly, implications for future research cooperatives and the broader HEAL data ecosystem are discussed.

Differential symptom weighting in estimating empirical thresholds for underlying PTSD severity: Toward a "platinum" standard for diagnosis?

OBJECTIVE

Symptom counts as the basis for Post-Traumatic Stress Disorder (PTSD) diagnoses in the DSM presume each symptom is equally reflective of underlying disorder severity. However, the "equal weight" assumption fails to fit PTSD symptom data when tested. The present study developed an enhanced PTSD diagnosis based on (a) a conventional PTSD diagnosis from a clinical interview and (b) an empirical classification of full PTSD that reflected the relative clinical weights of each symptom.

METHOD

Baseline structured interview data from Project Harmony (N = 2658) was used. An enhanced diagnosis for full PTSD was estimated using an empirical threshold from moderated nonlinear factor analysis (MNLFA) latent PTSD scale scores, in combination with a full conventional PTSD diagnosis based on interview data.

RESULTS

One in 4 patients in the sample had a PTSD diagnosis that was inconsistent with their empirical PTSD grouping, such that the enhanced diagnostic standard reduced the diagnostic discrepancy rate by 20%. Veterans, and in particular female Veterans, were at greatest odds for discrepancy between their underlying PTSD severity and DSM diagnosis.

CONCLUSION

Psychometric methodologies that differentially weight symptoms can complement DSM criteria and may serve as a platform for symptom prioritization for diagnoses in future editions of DSM.

Project Harmony: A Meta-Analysis With Individual Patient Data on Behavioral and Pharmacologic Trials for Comorbid Posttraumatic Stress and Alcohol or Other Drug Use Disorders

OBJECTIVE

Treatment efficacy for co-occurring posttraumatic stress disorder (PTSD) and substance use disorders is well established, yet direct evidence for comparative effectiveness across treatments is lacking. The present study compared the effectiveness of several behavioral and pharmacological therapies for adults with co-occurring PTSD and alcohol or other drug use disorders.

METHODS

A systematic search of PsycINFO, MEDLINE, and ClinicalTrials.gov was conducted through December 2020 for trials targeting PTSD, alcohol or other drug use disorders, or both disorders (36 studies, N=4,046). Primary outcomes were severity scores for PTSD, alcohol use, and drug use, estimated via moderated nonlinear factor analysis. Propensity score weight-adjusted multilevel models were used. Model-predicted effect sizes were estimated for each treatment, and comparative effect sizes for each active arm against treatment as usual, at end of treatment and at 12-month follow-up.

RESULTS

Compared with treatment as usual, combining trauma-focused therapy and pharmacotherapy for substance use disorders showed the largest comparative effect sizes for PTSD severity (d=-0.92, 95% CI=-1.57, -0.30) and alcohol use severity (d=-1.10, 95% CI=-1.54, -0.68) at end of treatment. Other treatments with large comparative effect sizes included pharmacotherapies for alcohol or other drug use disorders, trauma-focused integrated therapies, and trauma-focused nonintegrated therapies. Reductions in outcomes for PTSD symptoms and alcohol use were observed for nearly all treatments.

CONCLUSIONS

The findings provide support for treating comorbid PTSD and substance use disorders using a variety of approaches, with alcohol-targeted pharmacotherapies and trauma-focused behavioral therapies as a combination of treatments that lead to early and sustained improvements in PTSD and alcohol use severity. Further treatment development is indicated for combining behavioral and pharmacological treatments for synergized impact and understanding the mechanisms of action and conditions under which each treatment type is optimized.

Measurement Error-Corrected Estimation of Clinically Significant Change Trajectories for Interventions Targeting Comorbid PTSD and Substance Use Disorders in OEF/OIF Veterans

In randomized control trials (RCTs), a focus on average differences between treatment arms often limits our understanding of whether individuals show clinically significant improvement or deterioration. The present study examined differences in individual-level clinical significance trajectories between Concurrent Treatment of PTSD and Substance Use Disorders Using Prolonged Exposure (COPE) and Relapse Prevention (RP). Eighty-one treatment-seeking veterans with a comorbid PTSD/SUD diagnosis were randomized to COPE or RP; data from an additional n = 48 patients who did not meet criteria for both disorders was used to establish a normative threshold. A newly developed, modernized approach to the Jacobson and Truax (1991) clinically significant change framework, using (a) moderated nonlinear factor analysis (MNLFA) scale scoring and (b) measurement error-corrected multilevel modeling (MEC-MLM) was used; this approach was compared to other approaches using conventional total scores and/or assuming no measurement error. Using a conventional approach to estimating the Reliable Change Index (RCI) yielded no differences between COPE and RP in the percentage of patients achieving statistically significant improvement (SSI; 88.9% for both groups). However, under MNLFA/MEC-MLM, higher percentages of patients receiving COPE (75.0%) achieved SSI compared to RP (40.7%). Findings suggest that, even though COPE and RP appear to reduce the same number of PTSD symptoms, MNLFA scoring of outcome measures gives greater weight to interventions that target and reduce "hallmark" PTSD symptoms.

Estimating posttraumatic stress disorder severity in the presence of differential item functioning across populations, comorbidities, and interview measures: Introduction to Project Harmony

Multiple factor analytic and item response theory studies have shown that items/symptoms vary in their relative clinical weights in structured interview measures for posttraumatic stress disorder (PTSD). Despite these findings, the use of total scores, which treat symptoms as though they are equally weighted, predominates in practice, with the consequence of undermining the precision of clinical decision-making. We conducted an integrative data analysis (IDA) study to harmonize PTSD structured interview data (i.e., recoding of items to a common symptom metric) from 25 studies (total N = 2,568). We aimed to identify (a) measurement noninvariance/differential item functioning (MNI/DIF) across multiple populations, psychiatric comorbidities, and interview measures simultaneously and (b) differences in inferences regarding underlying PTSD severity between scale scores estimated using moderated nonlinear factor analysis (MNLFA) and a total score analog model (TSA). Several predictors of MNI/DIF impacted effect size differences in underlying severity across scale scoring methods. Notably, we observed MNI/DIF substantial enough to bias inferences on underlying PTSD severity for two groups: African Americans and incarcerated women. The findings highlight two issues raised elsewhere in the PTSD psychometrics literature: (a) bias in characterizing underlying PTSD severity and individual-level treatment outcomes when the psychometric model underlying total scores fails to fit the data and (b) higher latent severity scores, on average, when using DSM-5 (net of MNI/DIF) criteria, by which multiple factors (e.g., Criterion A discordance across DSM editions, changes to the number/type of symptom clusters, changes to the symptoms themselves) may have impacted severity scoring for some patients.

Design and methodology for an integrative data analysis of coping power: Direct and indirect effects on adolescent suicidality

As suicide rates have risen in the last decade, there has been greater emphasis on targeting early risk conditions for suicidality among youth and adolescents as a form of suicide "inoculation". Two particular needs that have been raised in this nascent literature are a) the dearth of examination of early intervention effects on distal suicide risk that target externalizing behaviors and b) the need to harmonize multiple existing intervention datasets for greater precision in modeling intervention effects on low base rate outcomes such as suicidal behaviors. This project, entitled "Integrative Data Analysis of Coping Power (CP): Effects on Adolescent Suicidality", funded by the National Institute of Mental Health (NIMH), will harmonize and analyze data from 11 randomized controlled trials of CP (total individual-level N = 3183, total school-level N = 189). CP is an empirically-supported, child- and family-focused preventive intervention that focuses on reducing externalizing more broadly among youth who exhibit early aggression, which makes it ideally suited to targeting externalizing pathways to suicidality. The project utilizes three measurement and data analysis frameworks that have emerged across multiple independent disciplines: integrative data analysis (IDA), random treatment effects multilevel modeling (RTE-MLM), and propensity score weighting (PSW). If successful, the project will a) provide initial evidence that CP would have gender-specific indirect effects on suicidality through reductions in externalizing for boys and reductions in internalizing for girls and b) identify optimal conditions under which CP is delivered (e.g., groups, individuals, online) across participants on reductions in suicidality and other key intermediate endpoints.

A systematic review and meta-analysis of psychological interventions for comorbid post-traumatic stress disorder and substance use disorder

BACKGROUND

The psychological treatment of comorbid post-traumatic stress disorder (PTSD) and substance use disorder (SUD) is clinically challenging, and outcomes are often poor.

OBJECTIVE

This paper describes a systematic review and meta-analysis which sought to establish the current efficacy for a number of established psychological approaches for adults and adolescents, in comparison to interventions for SUD alone, or other active approaches, following a pre-registered protocol.

METHOD

This review followed PRISMA and Cochrane Collaboration guidelines. Data extraction and risk of bias judgements using Cochrane criteria were undertaken by all authors. Primary outcomes were PTSD severity and substance use post-treatment. The quality of findings was assessed using GRADE. Following a comprehensive search, conducted to 13 September 2021, 27 studies were included.

RESULTS

We found a relatively high level of dropout across studies. In our main comparisons, we found no benefits for present-focused treatment approaches aimed at improving coping skills beyond those for SUD-only interventions. We found modest benefits for trauma-focused intervention plus SUD intervention post-treatment for PTSD (standardized mean difference (SMD) = -0.36, 95% confidence interval (CI) -0.64, -0.08), and at 6-13 months for PTSD (SMD = -0.48, 95% CI -0.81, -0.15) and alcohol use (SMD = -0.23, 95% CI -0.44, -0.02). There were no benefits for cognitive restructuring interventions as a group, but we found a modest effect for integrated cognitive behavioural therapy (ICBT) for PTSD post-treatment (SMD = -0.33, 95% CI -0.62, -0.04). There was evidence of some benefit for trauma-focused intervention over present-focused intervention for PTSD from a single study and for reduction in dropout for incentivized attendance for trauma-focused intervention from another single study. Most findings were of very low quality.

CONCLUSION

There is evidence that trauma-focused therapy and ICBT can improve PTSD for some individuals, but many patients do not fully engage with treatment and average treatment effects are modest.

HIGHLIGHTS

For PTSD, evidence was strongest for trauma-focused CBT-based approaches, but effects were modest.There was little evidence of any added benefit on substance use, beyond that of standard addiction treatments, for any included intervention.Dropout from treatment was high.