Effectiveness of the Unified Protocol for Transdiagnostic Treatment of Emotional Disorders Among Veterans With Posttraumatic Stress Disorder: A Pilot Study

Abstract

Effective treatment options are needed for veterans who do not participate in trauma-focused psychotherapy. Research has yet to examine the effectiveness of transdiagnostic psychotherapy in veterans with posttraumatic stress disorder (PTSD) and co-occurring psychological disorders. This pilot study examined the effectiveness of the Unified Protocol for Transdiagnostic Treatment of Emotional Disorders (UP) delivered in a 16-week group format. We examined treatment outcomes in male and female veterans (n = 52) in an outpatient specialty PTSD clinic at a large Veterans Affairs (VA) medical center. We hypothesized significant decreases in emotion regulation difficulty (Difficulties in Emotion Regulation Scale), PTSD symptom severity (PTSD Checklist for DSM-5), and depressive symptom severity (Patient Health Questionnaire–9). In addition, we hypothesized that reductions in emotion regulation difficulty across treatment would negatively predict PTSD and depressive symptoms at posttreatment. PTSD symptoms, depressive symptoms, and emotion regulation difficulty all evidenced significant improvements at the end of treatment relative to baseline (ps < .001). In addition, reductions in emotion regulation across treatment were associated with lower PTSD and depressive symptoms at posttreatment (ps < .001). This pilot study provides preliminary evidence supporting use of UP among veterans with PTSD and co-occurring disorders. Well-designed clinical trials evaluating efficacy of UP among veterans are needed.

Keywords

emotion regulation unified protocol PTSD veterans affairs transdiagnostic

The number of U.S. military veterans diagnosed with posttraumatic stress disorder (PTSD) has increased each year since the start of the conflicts in Iraq and Afghanistan (Seal et al., 2009). Low utilization of mental health services by this growing population presents a major public health concern (Hoge et al., 2014; Seal et al., 2010). Several effective interventions for PTSD are available (Institute of Medicine, 2008) including trauma-focused psychotherapies such as prolonged exposure (PE; Foa, Hembree, & Rothbaum, 2007) and cognitive processing therapy (CPT; Resick, Monson, & Chard, 2007), which have been implemented throughout the Department of Veterans Affairs (DVA) with good effect (Karlin et al., 2010). However, barriers to care are common (Seal et al., 2010). For example, despite DVA successfully training thousands of clinicians in PE and CPT, these interventions are often not used due to understaffing, large clinical caseloads, and incompatible clinic structures (Rosen et al., 2016). Thus, the development and implementation of new treatment options are needed, particularly group treatments that offset barriers.

Barriers of substantial concern include patient dropout, patient preference, and clinical presentations that include complex traumas and psychiatric comorbidities (Steenkamp, Litz, Hoge, & Marmar, 2015). A recent study found that only 41% of service members received an adequate dose of PTSD treatment after referral to a mental health clinic (Hoge et al., 2014). Low completion rates may be due, in part, to dropout motivated by patients’ preference to not participate in trauma-focused psychotherapy. Even in controlled clinical trials, approximately 25% of patients drop out from PE and CPT (Steenkamp et al., 2015).

Low completion rates may also be related to comorbidities that complicate treatment planning and engagement (Forbes, Creamer, Hawthorne, Allen, & McHugh, 2003). Veterans with PTSD often present with a number of comorbid conditions including problems involving depression and dysregulated affect (Marmar et al., 2015). Research (e.g., van Minnen, Harned, Zoellner, & Mills, 2012) has demonstrated that patients can benefit from trauma-focused psychotherapy despite carrying multiple comorbidities such as dissociation, borderline personality disorder, psychosis, substance use disorders, and major depression. However, a tension exists between these findings and day-to-day clinical practice. Many clinicians have concerns regarding comorbidities, which likely stems from clinicians’ direct experience with complex clinical cases and awareness that trauma-focused psychotherapy research trials have historically excluded patients with comorbid conditions (Spinazzola, Blaustein, & Van Der Kolk, 2005). Low motivation and low cognitive functioning may also interfere with treatment adherence (Cook, Dinnen, Simiola, Thompson, & Schnurr, 2014).

Effective transdiagnostic psychotherapies may provide a solution for patients and clinicians who collaboratively decide to pursue a nontrauma-focused treatment plan to address a range of psychiatric symptoms and low quality of life. Targeting transdiagnostic vulnerabilities within psychotherapy may be a parsimonious approach to treating complex clinical presentations, particularly presentations involving multiple emotional disorders (e.g., PTSD, depressive disorders, and anxiety disorders; Barlow et al., 2011). One such transdiagnostic vulnerability is difficulty in emotion regulation (Fairholme, Boisseau, Ellard, Ehrenreich, & Barlow, 2010; Gratz, Bardeen, Levy, Dixon-Gordon, & Tull, 2015; Sheppes, Suri, & Gross, 2015). Emotion regulation is defined as adaptive responding to emotional distress, requiring a repertoire that includes the awareness, understanding, and acceptance of emotions, the ability to inhibit impulses while engaging in goal-driven behavior in the presence of emotional distress, and the flexible and situationally appropriate use of strategies to modulate the course (i.e., intensity and duration) of emotions (Gratz & Roemer, 2004). Evidence suggests that emotion dysregulation is associated with several emotional disorders (Campbell-Sills, Barlow, Brown, & Hofmann, 2006; Eftekhari, Zoellner, & Vigil, 2009) and that improving emotion regulation predicts psychotherapy outcomes (Boden, Bonn-Miller, Kashdan, Alvarez, & Gross, 2013; Gratz, Weiss, & Tull, 2015).

The unified protocol (UP) for the transdiagnostic treatment of emotional disorders targets emotion regulation as a mechanism of change (Barlow et al., 2011; Fairholme et al., 2010). UP is the synthesis of common strategies used in empirically supported cognitive-behavioral therapies (CBTs; Norton & Paulus, 2016). Evidence supports UP for individuals diagnosed with anxiety disorders and mood disorders including four randomized controlled trials (Ciraulo et al., 2013; Farchione et al., 2012; Lotfi, Bakhtiyari, Asgharnezhad-Farid, & Amini, 2014; Mohammadi, Birashk, & Gharraee, 2014), two open trails (de Ornelas Maia, Braga, Nunes, Nardi, & Silva, 2013; de Ornelas Maia, Nardi, & Cardoso, 2014), and several case studies (Boisseau, Farchione, Fairholme, Ellard, & Barlow, 2010; Boswell, Anderson, & Barlow, 2014; Bullis et al., 2015; Ellard, Deckersbach, Sylvia, Nierenberg, & Barlow, 2012; Ellard, Fairholme, Boisseau, Farchione, & Barlow, 2010; Sauer-Zavala, Bentley, & Wilner, 2016). Furthermore, evidence suggests that improvements in anxiety, depression, and daily functioning are sustained for at least 18 months following UP completion (Bullis, Fortune, Farchione, & Barlow, 2014). In addition to symptom reduction, UP results in improvements in quality of life (Carl, Gallagher, Zavala, Bentley, & Barlow, 2014; Gallagher et al., 2013). In accordance with the UP theoretical model (Barlow et al., 2011), evidence suggests that UP may improve emotion regulation (Mohammadi et al., 2014; Sauer-Zavala et al., 2016) as well as the related constructs of emotional reactivity (Sauer-Zavala et al., 2012) and temperament (Carl et al., 2014).

In addition to anxiety and mood disorders, UP may be well suited for trauma-related pathology as PTSD has been conceptualized as a manifestation of emotion dysregulation following trauma (Seligowski, Lee, Bardeen, & Orcutt, 2015). From this perspective, weak inhibitory control of emotions is a vulnerability for reexperiencing and hyperarousal (Frewen & Lanius, 2006), and maladaptive avoidance to regulate reexperiencing stress maintains dysphoric emotions and additional hyperarousal (Gallagher, Thompson-Hollands, Bourgeois, & Bentley, 2015). Empirical evidence supports this view as emotion dysregulation is associated with PTSD (Boden et al., 2013; Bonn-Miller, Vujanovic, Boden, & Gross, 2011; Ehring & Quack, 2010; Moore, Zoellner, & Mollenholt, 2008; Tull, Barrett, McMillan, & Roemer, 2007). However, thus far, evidence supporting UP for PTSD and comorbidities is limited to case studies (Gallagher & Barlow, 2015).

To date, little research has examined the effectiveness of UP within a veteran sample or if UP treatment gains are associated with changes in emotion regulation skills, as proposed by treatment developers (Barlow et al., 2011). This pilot project evaluated the effectiveness of a 16-week, group-delivered UP trial by examining self-reported PTSD and depressive symptoms, as well as emotion regulation difficulties, during the first and final sessions. We anticipated effectiveness because group treatments for PTSD among civilians typically demonstrate significant pre–post effects on symptom severity reduction with dropout rates comparable with individual treatment (Sloan, Feinstein, Gallagher, Beck, & Keane, 2013). However, treatments are often less efficacious in veteran samples as compared with civilian samples (Bradley, Greene, Russ, Dutra, & Westen, 2005; Watts et al., 2013) including PTSD group therapies (Sloan et al., 2013). Even front-line trauma-focused psychotherapies have smaller effect sizes in this population when delivered in groups as opposed to individually (Resick et al., 2017). Thus, the effectiveness of UP delivered in groups and for veterans remains an open question.

Data were collected from a sample of mixed-gendered military veterans diagnosed with PTSD and comorbidities. First, we hypothesized that veterans receiving group-delivered UP would exhibit significant reductions in emotion regulation difficulties, PTSD symptoms, and depressive symptoms. Second, we hypothesized that reductions in emotion regulation difficulties would be negatively associated with PTSD and depressive symptom severity measured at posttreatment.

Method

Participants

This study was designed as an observation of a portion of veteran mental health care within a larger PTSD outpatient clinic (POC) at a large Veterans Affairs (VA) medical center. The POC has 12 staff members (e.g., psychologists, social workers) as well as rotating trainees who operate as members of the team. All providers in the POC function as independent providers who manage their own individual caseloads. As POC providers are referred patients from all over the hospital, it is their mission to determine whether PTSD related to military service is a key feature of the patient’s presenting issues, and if yes, engage the veteran in PTSD treatment planning. Each individual patient’s duration in the clinic varies widely, and patients often receive more than one episode of care over the course of their time in POC. Participation in POC services is not exclusive, and many patients opt to obtain psychiatric medication services as well as other services throughout VA and the private community as they see fit.

Accordingly, participants were not included in the UP groups based on formal inclusion and exclusion criteria. Information about participants’ diagnoses and medications were obtained by a review of the medical record. All participants had a diagnosis of PTSD, as this is a requirement for receiving care in the POC. Diagnoses and referrals were managed using standard clinical procedures, which typically include a semistructured clinical interview. Each clinician was practicing within his or her own clinical judgment; there was not a formal decision tree process that dictated which referrals were sent to UP and which were sent elsewhere. Clinicians judged appropriateness of patient referral to the UP group based on a number of factors. Clinicians often considered patient’s readiness for trauma-focused treatment or patient preference for nontrauma-focused treatment when making referrals. Patients with active substance dependence (e.g., unmanaged substance use that was not a treatment target) or significant harm potential to self or others (e.g., suicidal or homicidal intention or behaviors that involved a level of imminent risk beyond low) were typically not referred to UP.

Of 170 veterans who initiated the UP group, 150 veterans consented to participate in data collection and returned survey packets to experimenters after the first session. Ten participants returned surveys with incomplete data (>12% missing data on PTSD Checklist for DSM-5 [PCL-5], Patient Health Questionnaire–9 [PHQ-9], and/or Difficulties in Emotion Regulation Scale [DERS]). Of 140 participants, who sufficiently responded to the first session survey packet, 52 participants completed and returned final session survey packets. All final session survey packets were completed sufficiently (<12% missing data). All missing items in the final data set were replaced by the mean of the participant’s completed responses within the given measure.

Final analyses used only the 52 veterans who completed first session and final session survey packets. Veterans may have not provided final session data for several reasons: treatment dropout (barriers to care, nonresponding, or early responding), changes to preferences or availability, absence during the final session, refusal to continue research participation, and forgetting to return survey packet. This study emphasizes ecological validity by assessing outcomes of a novel intervention in routine clinical care. As such, this study did not use monetary incentives, independent evaluators, or patient tracking to facilitate outcome assessment at posttreatment or follow-up. Data are not available to determine reasons why 62% of participants did not return final survey data. Thus, a true attrition or dropout rate is not available. In a review of PTSD group treatments, dropout rates ranged from 0% to 52%, though the definition for dropout varied considerably (Sloan et al., 2013).

Demographic and diagnostic information was collected from each veteran’s medical record. The medical record is maintained and updated by clinicians in the POC as well as providers throughout the VA health care system. Of those who completed the first and last session, the mean age was 46.65 years (SD = 12.50). Forty-three veterans were men (82.7%) and nine were women (17.3%). In terms of race, 34 veterans were identified as White (65.4%), five as black (9.6%), two as Native Hawaiian/Pacific Islander (3.8%), two as Asian American (3.8%), and nine chose not to disclose (17.3%). Ten veterans indicated Latino ethnicity (19.2%). All veterans had a diagnosis of military-related PTSD, and only eight carried PTSD as his or her only mental health disorder (15.4%). The number of psychiatric comorbidities ranged from zero to four. Thirty were diagnosed with a depressive disorder (57.7%), 20 with a sleep–wake disorder (38.5%), 18 with substance use disorder (34.6%), 10 with an anxiety disorder (19.2%), four with bipolar disorder (7.7%), and one with schizophrenia (1.9%). In total, veterans averaged 2.71 mental health diagnoses including PTSD (SD = 1.05). Forty participants were prescribed with a least one psychiatric medication (76.9%). The number of psychiatric medications ranged from zero to five with an average number of 1.67 prescriptions (SD = 1.32).

Measures

DERS

The DERS (Gratz & Roemer, 2004) is a questionnaire that uses 36 5-point scaled items to assess difficulty in adaptive emotion regulation. Items reflect difficulties in the following skills: emotional awareness, emotional clarity, emotional acceptance, impulse control, ability to persist in goal-directed behavior when experiencing negatively valenced emotions, and access to specific adaptive emotion regulation strategies when experiencing negatively valenced emotions. Example items include “When I’m upset, I have difficulty controlling my behaviors,” and “When I’m upset, it takes me a long time to feel better.” Scores with higher values indicate greater difficulty in emotion regulation (1 = almost never to 5 = almost always). The DERS overall score has demonstrated strong psychometric properties (Bardeen, Fergus, & Orcutt, 2012; Gratz & Roemer, 2004). Cutoff scores to identify pathological levels of dysregulation have not yet been determined empirically. Internal consistency for the total score within the current study was excellent (first session: α = .91; final session: α = .96).

PCL-5

The PCL-5 (Weathers et al., 2013) is a 20-item self-report questionnaire corresponding to the Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5; American Psychiatric Association, 2013) criteria for PTSD. Findings from a large study using a PTSD treatment–seeking military sample support the PCL-5’s internal consistency, convergent and discriminant validity, sensitivity to clinical change, and diagnostic utility (Wortmann et al., 2016). PCL-5 items represent the 20 DSM-5 symptoms of PTSD, and scores with higher values indicate greater symptom severity (0 = not at all to 4 = extremely). Internal consistency within the current study was excellent (first session: α = .91; final session: α = .95). The clinically significant cutoff for the PCL-5 is 33 (Wortmann et al., 2016).

PHQ-9

The PHQ-9 (Kroenke & Spitzer, 2002) is a nine-item self-report measure of depressive symptoms. Scores with higher values indicate greater symptom severity (0 = not at all to 3 = nearly every day). Evidence supports its reliability, validity, and sensitivity to clinical change (Löwe, Unützer, Callahan, Perkins, & Kroenke, 2004). Internal consistency within the current study was good (first session: α = .86; final session: α = .91). The clinically significant cutoff for the PHQ-9 is 11 (Manea, Gilbody, & McMillan, 2012).

Procedure

All study procedures were reviewed and approved by the appropriate Institutional Review Board. Data were collected as part of routine clinical care at a POC. All participants carried a military-related PTSD diagnosis (DSM-5 criteria) that was confirmed during intake session conducted by one of the clinic’s licensed clinicians (social worker or clinical psychologist) or a trainee supervised by a licensed clinician. All participants were referred to the UP group based on a treatment plan constructed collaboratively by the intake clinician and veteran.

Once veterans were referred to UP group, during their initial session, a representative from the study came to provide informed consent. Veterans were provided with an information statement detailing the purpose of the study, benefits, and limitations, as well as contact information for researchers as needed. Consenting was always conducted by a licensed clinical psychologist and was never conducted by a group facilitator to reduce any undue influence on veterans to participate. Participation was completely voluntary, and veterans were not provided with financial compensation. Data were deidentified and entered into a database by a research assistant unaffiliated with the delivery of clinical care. Data analyses were conducted by the principal investigator (a clinical psychologist) and a psychology intern working under her supervision.

Delivery of UP

UP is designed to be a flexible treatment, and the manual does not strictly dictate session length or number of sessions required (Barlow et al., 2011). UP includes eight modules that are provided sequentially and flexibly: (a) increasing motivation for change, (b) learning to monitor objective and subjective facets of emotion, (c) cultivate nonjudgmental emotional awareness, (d) develop cognitive reappraisal skills, (e) identify and modify maladaptive avoidance and emotion-driven behaviors, (f) enhance ability to tolerate physical sensations of emotions, (g) engage in interoceptive and in-vivo exposures, and (h) incorporate learned skills to prevent future relapse.

Guidance from treatment developers indicates that when applied individually, UP can be self-paced with a varying number of sessions (Barlow et al., 2011). Research on UP administered in an individual format has included session length ranging from 50 to 60 min, and total number of sessions ranging from 12 to 18 (Boisseau et al., 2010; Farchione et al., 2012). As this study included UP administration in a group format, it was determined to administer the content over 16 sessions lasting 90 min per session to occur one time per week. UP was always delivered by at least one licensed clinical psychologist who was trained via a workshop conducted by UP developers. Several groups had a cofacilitator who was a licensed social worker, licensed clinical psychologist, or predoctoral psychology intern. Data collected for the purposes of this study were assessed during the first session and final session.

Data Analyses

First, analyses were conducted to rule out the possibility of systematic biases, namely, gender differences in outcomes and differences between those who did and did not complete final session data. Second, zero-order correlations were explored between outcomes and potential correlates of age and number of psychiatric diagnoses. Third, to test intervention effectiveness, pre–post effects for DERS, PHQ-9, and PCL-5 were analyzed using three separate repeated measures analysis of variances (ANOVAs). Fourth, to test emotion regulation as a potential change mechanism in outcome reduction, hierarchical linear regression (HLR) analyses were used for predicting final session outcomes with DERS change scores (controlling for first session outcomes). Fifth, to explore the directionality of a potential relationship between changes in emotion regulation difficulty and clinical outcomes, additional HLRs were conducted in which changes in symptom severity were used to predict final session emotion regulation difficulty.

Results

To examine the potential for baseline differences between those who did (n = 52) and did not (n = 88) provide final session data, the two groups were compared on all first session symptom variables (DERS [p = .54], PHQ-9 [p = .34], PCL-5 [p = .11]), and no significant differences emerged. There were no gender differences on first session or final session DERS, PHQ-9, or PCL-5. Associations were explored using zero-order correlations between DERS, PHQ-9, PCL-5, age, and number of psychiatric diagnoses at each time point (see Table 1). Age was negatively related to DERS during the first session, r(50) = −.29, p = .034, and the final session, r(50) = −.30, p = .028. Therefore, age was included as a covariate when testing hypotheses.

Table 1.

Correlations and Pre–Post Effects (n = 52).

Measures	1	2	3	4
1. DERS Total Score	—	.55***	.56***	−.29*
2. PHQ-9 Total Score	.72***	—	.72***	−.20
3. PCL-5 Total Score	.79***	.83***	—	−.23
4. Age	−.30*	−.18	−.20	—
M (SD)—Time 1	125.39 (19.98)	16.82 (5.95)	56.47 (13.25)
M (SD)—Time 2	109.12 (29.35)	14.03 (6.68)	49.67 (17.90)
Hedges’s g	0.64	0.44	0.43
F	31.96***	24.16***	16.29***
$η_{p}^{2}$	.385	.321	.242

Note. Values above the diagonal are from first session data. Values below the diagonal are from final session data. DERS = Difficulties in Emotion Regulation Scale; PHQ-9 = Patient Health Questionnaire–9; PCL-5 = PTSD checklist for DSM-5; PTSD = posttraumatic stress disorder; DSM-5 = Diagnostic and Statistical Manual of Mental Disorders (5th ed.).

p < .05. **p < .01. ***p < .001.

To test intervention effectiveness (first hypothesis), pre–post effects for DERS, PHQ-9, and PCL-5 were analyzed using three separate repeated measures ANOVAs. As anticipated, these analyses revealed significant pre–post reductions in emotion regulation difficulty (DERS), depression severity (PHQ-9), and PTSD symptom severity (PCL-5; see Table 1 for effect size estimates using Hedges’s g). At the initial time point, 3.8% of patients were below the suggested clinical cutoff on the PCL-5, while 15.4% were below the clinical cutoff of the PHQ-9. At the final session, 15.4% were below the clinical cutoff of the PCL-5, while 36.5% were below the clinical cutoff of the PHQ-9. The final session PCL-5 and PHQ-9 mean scores were above screening cutoff recommendations for PTSD and depressive disorders, respectively.

To test emotion regulation as a change mechanism in PTSD symptom severity reduction (second hypothesis), an HLR was used for predicting final session PCL-5 total score with first session PCL-5 total score, and age was entered as the first step and DERS change score was entered as the second step (i.e., first session DERS total minus final session DERS total). As seen in Table 2, findings indicate that the second step significantly predicted final session PCL-5 scores (ΔR² = .20, p < .001). Consistent with the hypothesis, beta scores indicate that higher reductions in DERS predicted lower PCL-5 scores measured on the final session.

Table 2.

Predicting Final Session PCL-5.

Step	Independent Variables	Betas/R²
1	Age	−.03
	PCL-5 first session	.73***
	Multiple R²	.54***
2	Age	.02
	PCL-5 first session	.65***
	DERS change score	−.46***
	Multiple R²	.74***
	ΔR²	.20***

Note. PCL-5 = PTSD checklist for DSM-5; PTSD = posttraumatic stress disorder; DSM-5 = Diagnostic and Statistical Manual of Mental Disorders (5th ed.); DERS = Difficulties in Emotion Regulation Scale.

***

p < .001.

To test emotion regulation as a change mechanism in depression symptom severity reduction (second hypothesis), an HLR was used predicting final session PHQ-9 total score with first session PHQ-9 total score and age entered as the first step and DERS change score entered as the second step. As seen in Table 3, findings indicate that the second step significantly predicted final session PHQ-9 scores (ΔR² = .10, p < .001). Consistent with the hypothesis, beta scores indicate that higher reductions in DERS predicted lower PHQ-9 scores measured on the final session.

Table 3.

Predicting Final Session PHQ-9.

Step	Independent Variables	Betas/R²
1	Age	−.02
	PHQ-9 first session	.79***
	Multiple R²	.64***
2	Age	.02
	PHQ-9 first session	.72***
	DERS change score	−.33***
	Multiple R²	.74***
	ΔR²	.10***

Note. PHQ-9 = Patient Health Questionnaire–9; DERS = Difficulties in Emotion Regulation Scale.

***

p < .001.

The second hypothesis was supported by HLRs indicating that reductions in emotion regulation difficulty were negatively associated with final session symptom severity (PTSD and depression). To explore the directionality of these potential effects between emotion regulation difficulty and clinical outcomes, two additional HLRs were conducted in which changes in symptom severity were used to predict final session emotion regulation difficulty. If symptom reductions are negatively correlated with final session emotion regulation difficulty, then the directionality of the purported mechanism–outcome relationship is unclear. The first HLR predicted final session DERS total score with first session in DERS total score and age entered as the first step and PCL-5 change score entered as the second step (i.e., first session PCL-5 minus final session PCL-5). As seen in Table 4, findings indicate that the second step significantly predicted final session DERS total scores (ΔR² = .11, p < .001), and beta scores indicate that higher reductions in PHQ-9 predicted lower DERS scores at the final session. The second HLR revealed similar findings. The HLR predicted final session DERS total score with first session in DERS total score and age entered as the first step and PHQ-9 change score entered as the second step (i.e., first session PHQ-9 minus final session PHQ-9). As seen in Table 4, findings indicate that the second step significantly predicted final session DERS total scores (ΔR² = .22, p < .001), and beta scores indicate that higher reductions in PCL-5 predicted lower DERS scores at the end of treatment.

Table 4.

Predicting DERS with Symptom Change.

Step	Independent Variables	PCL-5 total score	PHQ-9 total score
Step	Independent Variables	Betas/R²	Betas/R²
1	Age	−.11	−.11
	DERS first session	.68***	.68***
	Multiple R²	.51***	.51***
2	Age	−.12	−.11
	DERS first session	.58***	.65***
	PCL-5 change score	−.48***
	PHQ-9 change score		−.33**
	Multiple R²	.73***	.62***
	ΔR²	.22***	.11**

Note. DERS = Difficulties in Emotion Regulation Scale; PCL-5 = PTSD checklist for DSM-5; PTSD = posttraumatic stress disorder; DSM-5 = Diagnostic and Statistical Manual of Mental Disorders (5th ed.); PHQ-9 = Patient Health Questionnaire–9.

p < .01. ***p < .001.

Discussion

Following participation in group-delivered UP, veterans with PTSD and various comorbidities reported a significant reduction in emotion regulation difficulties and severity in depressive and PTSD symptoms relative to their reports at the beginning of treatment. The pre–post effect sizes were comparable with other PTSD group treatments using veteran participants (Sloan et al., 2013). Furthermore, in accordance with the UP theoretical model (Barlow et al., 2011), reductions in emotion regulation difficulties negatively predicted PTSD and depressive symptom severity at the end of the UP group. These findings build on previous positive findings for UP (Ellard et al., 2010; Farchione et al., 2012) and extend the findings to a group therapy format with veterans diagnosed with PTSD.

Implications

The magnitude of the pre–post effects for symptom reduction was modest and many veterans still reported significant symptoms at posttreatment. However, even small improvements in clinical symptoms and underlying mechanisms are meaningful given that the sample was referred to UP, in part, due to low clinician-assessed readiness for evidence-based, trauma-focused PTSD interventions (Kraemer & Kupfer, 2005). Also, modest effects in PTSD treatments are not surprising given that approximately two thirds of active duty and veteran patients receiving evidence-based psychotherapy for PTSD have been shown to retain their diagnosis of PTSD at posttreatment (Steenkamp et al., 2015). Clearly, innovations in therapeutic approaches need to continue. Alternative PTSD treatment approaches, particularly those such as UP that can accommodate several comorbidities, should receive additional research attention to explore efficacy as potential options. The pilot data in the current study warrant consideration of testing UP in the veteran population using a randomized controlled design with gold standard methods recommended for PTSD clinical trials (Harvey, Bryant, & Tarrier, 2003).

In this study, UP was delivered as stand-alone treatment, and patients were given the option of doing PE or CPT afterward. Future research should explore using UP as a precursor to trauma-focused psychotherapies. As a CBT, UP’s underlying framework and targeted skills are consistent with PE and CPT. Even though clinical symptoms in the current study largely remained above diagnostic thresholds, one possibility is that improvements in emotion regulation via UP can support engagement and improve clinical outcomes from subsequent trauma-focused psychotherapy. For example, improved emotion regulation skills may widen the window of tolerability required for effective interventions emphasizing exposure and reappraisal of trauma content. Alternatively, for patients who accomplish only partial recovery in trauma-focused psychotherapy, UP may be a useful aftercare strategy to support additional incremental gains, consolidate improvement, and prevent relapse.

To date, emotion regulation as an UP mechanism is primarily supported by theory (Barlow et al., 2011) and lacks evidence required to establish a mechanism of change, such as mechanism–outcome associations, mechanism–outcome temporal precedence, and experimental evidence (Kazdin, 2007). The current study extends the UP literature by demonstrating the purported mechanism (i.e., emotion regulation) and outcome that covary across treatment. Importantly, even though veterans participated in groups with peers with relatively heterogeneous clinical presentations, UP treatment gains were related to improvements in the one transdiagnostic vulnerability. However, this study provides no insights regarding mechanism–outcome directionality. Future investigations of UP mechanisms of change will benefit from conducting experimental designs within clinical trials and laboratory settings.

Limitations

A strength of this study is its summary of routine clinical data. These findings may generalize well to other VA outpatient PTSD clinics for veterans who complete participation in UP. However, generalizability to other settings may be restricted by sample characteristics (e.g., small number of participants, all of whom are veterans, and with low proportions of women and non-White veterans). In addition, well-designed trials are needed to determine the efficacy of UP among veterans. The lack of control group precludes insights regarding the cause of pre–post effects. Future studies should address the limitations of this pilot by comparing UP with a control condition, stabilizing other mental health treatments, utilizing blind outcome assessment with clinician-rated interviews for key diagnoses, and assessing outcomes several months after treatment completion. The self-report measures used, and sourcing of diagnostic information from medical chart review, present another potential limitation. To assess the efficacy of UP for a range of comorbidities of PTSD, future trials should consider assessing a wide spectrum of psychiatric symptoms, that is, beyond PTSD and depression. Furthermore, analyses only used participants who completed data collection during the first session and final session. It is possible that there were systematic differences between those who did and did not attend the final session that went undetected. Future clinical trials should utilize intent-to-treat analyses and retain all participants who start treatment in all data collection time points.

Conclusion

Many clinics are not equipped to provide evidence-based trauma-focused psychotherapy such as PE and CPT (Rosen et al., 2016). Furthermore, clinicians in specialty PTSD clinics report that many of their patients are not good candidates for trauma-focused psychotherapy (Cook et al., 2014). Given the high prevalence and complicated presentation of co-occurring conditions among patients with PTSD (Marmar et al., 2015), it is critical that the effectiveness of a range of therapeutic interventions is evaluated for this population, especially transdiagnostic treatments that can be delivered in groups and with flexibility to meet patient needs. The current study provides evidence to inform future research on UP and supports its consideration for the treatment of veterans with PTSD and co-occurring disorders. Given the meaningful proportion of veterans in specialty PTSD clinics who do not participate in trauma-focused treatment (Rosen et al., 2016) or benefit if they do participate (Steenkamp et al., 2015), future studies will profit from examining whether UP serves as an effective stand-alone treatment or a “gateway” intervention that facilitates veterans’ future engagement in front-line treatments.

Footnotes

Acknowledgements

The authors thank the clinical staff at the PTSD outpatient clinic at VA Puget Sound Health Care System—American Lake Division as well as the research support staff, Ms. Laurie Maus and Mr. John Lapinski, without whom this project would not be possible.

Author’s Note

This research was conducted at VA Puget Sound Health Care System—American Lake Division, Tacoma, WA. A.M.S. is now at the Emory School of Medicine, Atlanta, GA. The contents do not represent the views of the U.S. Department of Veterans Affairs or the U.S. government.

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

Author Biographies

Ruth L. Varkovitzky, PhD, is a staff psychologist in the Western Telemental Health Network within VA Puget Sound Health Care System at the American Lake Division in Tacoma, Washington. She is a clinical assistant professor at the University of Washington School of Medicine in the Department of Psychiatry and Behavioral Sciences. She participates in provision of clinical services over telehealth, supervision of trainees and program evaluation.

Andrew M. Sherrill is a postdoctoral fellow in the Department of Psychiatry and Behavioral Sciences at the Emory University School of Medicine in Atlanta, Georgia. He conducts research, clinical work, and consultation with the Emory Healthcare Veterans Program.

Greg M. Reger, PhD, is the deputy associate chied of Staff at the VA Puget Sound Health Care System and Associate Professor of Psychiatry and Behavioral Sciences at the University of Washington School of Medicine. Dr. Reger’s research has focused on the design and evaluation of technologies to support the psychological health of veterans and military personnel, particularly as it relates to anxiety and trauma.

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