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. Author manuscript; available in PMC: 2023 May 1.
Published in final edited form as: Psychol Trauma. 2021 Nov 29;14(4):605–614. doi: 10.1037/tra0001119

Do Older Veterans Experience Change in Posttraumatic Cognitions Following Treatment for Posttraumatic Stress Disorder?

Stephanie Y Wells 1,2,3, Kristen H Walter 1,4, Eric A Dedert 2,3,5, David R Strasshofer 2, Janina S Schnitzer 4, Steven R Thorp 6, Leslie A Morland 1,4,7, Lisa H Glassman 1,7
PMCID: PMC9639672  NIHMSID: NIHMS1738573  PMID: 34843355

Abstract

Objective:

It is unclear whether PTSD treatments improve negative posttraumatic cognitions (NPCs) and if changes in NPCs mediate treatment outcomes in older veterans. The current study examined if prolonged exposure therapy (PE) and relaxation therapy (RT) reduce NPCs over time in older adult veterans with PTSD.

Method:

This study analyzed data from a randomized controlled trial of eighty-six older male veterans with PTSD randomized to PE or RT. The Posttraumatic Cognitions Inventory (PTCI), which includes a total score and three subscales, negative cognitions of the self (Self), negative cognitions of the world (World), and self-blame (Blame), was used to assess NPCs at pretreatment, posttreatment, and 6-month follow-up.

Results:

Changes in NPCs differed by treatment condition. Veterans who received PE had significantly reduced overall NPCs and NPCs about the self at posttreatment but these NPCs were no longer significantly different from baseline at the follow-up assessment. In contrast, NPCs about the world and self-blame did not significantly change following PE. NPCs did not change following RT. Effects of PE on decreased 6-month follow-up clinician-rated PTSD symptoms were conveyed through intervening effects of decreased posttreatment PTCI total scores, suggesting the utility of targeting posttraumatic cognitions as a mechanism of long-term PTSD symptom reduction.

Conclusions:

Given that reductions in overall negative cognitions are associated with lower clinician-administered PTSD scores six months after PE, clinicians could consider monitoring changes in these cognitions over the course of treatment. RT is not a recommended treatment approach to target NPCs in older adults with PTSD.

Keywords: Prolonged exposure, relaxation therapy, older adults, veterans, posttraumatic cognitions

Introduction

Negative posttraumatic cognitions (NPC) following trauma can lead to the development and maintenance of posttraumatic stress disorder (PTSD; LoSavio et al., 2017). NPCs are related to PTSD severity, and changes in posttraumatic cognitions precede and mediate PTSD symptom change (e.g., McLean et al., 2015; Schumm et al., 2015; Zalta et al., 2014). Fortunately, evidence-based PTSD treatments, such as prolonged exposure (PE; Foa et al., 2019), reduce NPCs in several populations, such as female sexual assault survivors and adults with various trauma exposures (e.g., terrorist attack, combat; Foa & Rauch, 2004; Hagenaars et al., 2010; Nacasch et al., 2015). Although these findings suggest that PE can successfully decrease negative trauma-related cognitions, no studies have examined whether negative cognitions decrease following PE in older veterans.

The number of older veterans is increasing, and so is their healthcare utilization (Wierchers et al., 2015). Older adults receive less mental health treatment when compared to younger groups (Smith et al., 2016), which may be related to entrenched NPCs about the self (e.g., “I’m unable to improve after this long”; “nothing can help me”). However, research examining outcomes of evidence-based PTSD treatments and their impact on NPCs among older veterans remains limited, and there may be unique considerations for older veterans.

Examining NPCs among older adult veterans may be particularly salient because individuals tend to adopt an overall positive or negative valuation of their life experiences with increased age (Joseph & Linley, 2005). Thus, older adult veterans who have experienced traumatic events may be at greater risk for negative valuations and more rigid posttraumatic beliefs. Older veterans’ posttraumatic cognitions may also be more entrenched than those of younger veterans as more time has passed since the traumatic event(s). Further, memories are state-dependent (Bower, 1981); if older adults spend significant time in a negative mood state due to PTSD, anxiety, or depression, they may be more likely to frequently recall traumatic experiences and NPCs. Cognitive flexibility also declines in older adulthood (Harada et al., 2013); as a result, older adult veterans may have more difficulty changing existing posttraumatic beliefs. Finally, Socioemotional Selectivity Theory (Carstensen, 1995) proposes that goals for social interaction naturally change over the lifespan. As individuals near the end of life and have less time left, emotion regulation through social interactions becomes increasingly aimed at emotional regulation rather than information seeking or meeting unfamiliar people (Carstensen, 1995). Thus, people will primarily associate with individuals who are familiar to them to provide comfort (Carstensen, 1995). As a result, older adults often interact with a smaller group of individuals. For individuals with PTSD, social networks may be further limited by negative posttraumatic cognitions. For example, negative beliefs about others’ trustworthiness or negative beliefs about oneself (e.g., I am worthless) may interfere with social interactions with even familiar individuals. Additionally, a smaller support network may make it more difficult to challenge negative beliefs about others and the world due to fewer opportunities. Given these special considerations for older adults, it is possible that changes in posttraumatic beliefs may be attenuated following evidence-based PTSD treatment.

PE may be particularly well suited to change NPCs. PE is an exposure-based trauma-focused therapy that includes psychoeducation, breathing retraining, and in-vivo and imaginal exposures. PE helps individuals approach trauma-related memories and stimuli through imaginal and in-vivo exposures in order to activate trauma-related emotion networks and help disconfirm negative trauma-related beliefs through new learning opportunities. Through repeated imaginal exposures, individuals’ memories become less fragmented and one’s ability to tolerate trauma-related stress may increase, which can challenge NPCs (e.g., “I could have prevented the trauma”; “I am too weak to handle thinking about my trauma”). Additionally, engaging in in-vivo exposures without the presence of the feared outcome can also promote new learning and disconfirm NPCs. PE has been shown to significantly reduce NPCs in various samples (Foa & Rauch, 2004; Hagenaars et al., 2010; Nacasch et al., 2015) whether older veterans can experience change following PE, and the degree of change, remain empirical questions.

Relaxation therapy (RT) can also be used to improve PTSD symptoms. A previous study found that relaxation therapy improved PTSD symptoms in a civilian sample of adults of mixed ages, although PE had a greater impact on PTSD symptoms than RT (Taylor et al., 2003). RT is proposed to work through decreasing anxiety and physiological reactivity and promoting decentering (i.e., the ability to observe thoughts with a nonjudgmental stance; Hayes-Skelton et al., 2015; Taylor et al., 2003). Additionally, RT may increase one’s sense of control and self-efficacy through learning to regulate their own physiological arousal and emotional state. While NPCs are not a specific target of RT, it may help improve NPCs. For example, if individuals have improved self-efficacy and a sense of control, individuals may change negative beliefs about themselves (e.g., I am unable to control my emotions) and the world (e.g., If I go in public, I will become too overwhelmed and not be able to handle it). Further, if individuals are better able to decenter from their thoughts, they may be able to change them more easily by recognizing they are just thoughts and not facts.

The Present Study

The present study presents new data from a parent RCT (Thorp et al., 2019) for peer review) that compared PE and relaxation therapy (RT) among 86 older adult male veterans with combat or military-related PTSD. The larger study found that clinician-rated PTSD symptoms significantly improved for veterans in both PE and RT, but the groups did not differ across time points, suggesting that neither treatment significantly outperformed the other through 6-month follow-up. However, effect sizes for clinician-rated PTSD were larger from pre to posttreatment for veterans who received PE as compared to those who received RT, though symptoms rebounded for both groups in the six-month follow-up period. For self-reported PTSD symptoms, veterans who received PE showed a greater rate of change from pre to posttreatment, but also a greater rebound effect from posttreatment to 6-month follow-up. The larger study did not examine changes in posttraumatic cognitions.

The current study expands upon the existing literature by: (1) determining whether PE and RT reduce NPCs over time in older adult veterans with PTSD; (2) evaluating whether changes are greater for veterans who received PE than for those who received RT; and 3) exploring the potential intervening role of NPCs on PTSD and depressive symptom outcomes. Based on the findings from the parent trial (Thorp et al., 2019), we hypothesized that PE would result in significant reductions in overall posttraumatic cognitions and the associated subtypes (e.g., self, world, and self-blame) from pre to posttreatment, but that posttraumatic cognitions would no longer be statistically significantly different from baseline at the 6-month follow-up due to the rebound effect for PTSD symptoms found in the parent trial. RT is proposed to increase self-efficacy, decrease arousal, heighten a sense of control, and help individuals to identify thoughts and feelings more objectively (Hayes-Skelton et al., 2015); however, none of these proposed mechanisms are designed to address maladaptive cognitions. Therefore, our second hypothesis was that, relative to veterans receiving RT, veterans receiving PE would have greater reductions in overall posttraumatic cognitions and specific subtypes (i.e., negative beliefs about the self [Self], negative beliefs about world [World], and self-blame [Blame]) at posttreatment, but not at 6-month follow-up. Finally, we hypothesized that there would be an intervening effect of posttreatment PTCI total scores on the effect of treatment condition on PTSD and depressive symptoms at 6-month follow-up, such that PE-related reductions in posttraumatic cognitions will be related to lower PTSD and depressive symptoms at the 6-month follow-up.

Method

Participants

The study included 86 older adult male combat veterans with military-related PTSD who participated in an RCT of PE (n = 40) and RT (n = 46). Participants had a mean age of 65.09 years (range = 60–88; SD = 5.18); the majority of participants were White (75.5%), married (69.9%), and served in the Vietnam era (86.3%). Individuals were randomized into either PE (48.2%) or RT (51.8%). Participants who received PE significantly differed from those who received RT on pretreatment PTCI total scores (t[72] = 2.42, p = .02; M = 36.98, SD = 6.25 vs. M = 32.15, SD = 5.15), and the World (t[79] = 2.62, p = .01; M = 9.83, SD = 1.59 vs. M = 8.36, SD = 1.28) and Blame (t[81] = 2.96, p = .004; M = 5.88, SD = 0.93 vs. M = 7.78, SD = 1.19 vs.) subscales; they did not differ on pretreatment Self subscale scores (t[74] = 1.80, p = .08), respectively. Additional information, group comparisons, and methodology descriptions have been published (Thorp et al., 2019). All participants provided informed consent and all procedures were approved by the (Thorp et al., 2019).

Inclusion criteria for the RCT required being: (1) male; (2) a U.S. veteran; (3) 60 years of age or older; (4) literate in the English language; and (5) diagnosed with PTSD with a clear memory of a military-related criterion A event using the Clinician-Administered PTSD Scale for DSM-IV (Blake et al., 1995). Participants in the current study also needed to have PTCI subscale data from at least one assessment time point. Only one individual was removed from the original sample because they did not have PTCI data at any time point. Additional exclusion criteria from the parent study consisted of individuals who: (1) received concurrent psychotherapy targeting PTSD or depressive symptoms; (2) experienced manic episodes or unmanaged psychosis in the past year; (3) screened positive for substance dependence in the past two months; (4) had a significant respiratory or cardiovascular disease that affected therapy attendance; or (5) reported a lifetime history of head injury with loss of consciousness longer than 20 minutes.

Procedure

Recruitment occurred between 2009 and 2013 at a Southwestern VA Medical Center. Veterans were recruited using posted flyers and referrals from VA clinic providers. To assess for potential eligibility, veterans first completed a telephone screen. If deemed initially eligible following the telephone screen, veterans were scheduled for an in-person baseline assessment to determine final eligibility. If eligible for the study following the baseline assessment, veterans completed 12 sessions of individual therapy, a posttreatment assessment, and a 6-month follow-up assessment. Veterans were compensated $40 for each study assessment that they completed. All procedures were approved by the San Diego VA Health Care System Institutional Review Board.

Treatment

Veterans were randomized to either PE or RT; treatment was consistent with the respective study protocols (Foa et al., 2007; Taylor et al., 2003). Each therapy consisted of 12 weekly sessions that were 90-minutes in duration and delivered in an individual face-to-face format. Both PE and RT were provided by licensed clinical psychologists and social workers trained in both protocols. To ensure fidelity, therapists attended clinical consultation every week that included didactic training, case discussion, and review of video recorded sessions.

Prolonged exposure.

Following the PE protocol, veterans randomly assigned to PE learned how to use breathing retraining, engaged in imaginal exposures (i.e., repeatedly verbally recounted their most distressing trauma memory aloud in session), completed in-vivo exposures (e.g., approached feared but safe situations), and completed homework assignments (e.g., listened to audio recordings of the sessions, conducted in-vivo exposures).

Relaxation therapy.

Veterans randomly assigned to the RT condition were taught how to engage in systematic relaxation through tensing and relaxing 16 different muscle groups (i.e., progressive muscle relaxation), while also using pleasant imagery and relaxing words. As therapy progressed, veterans reduced the number of muscle groups that they targeted during practice and started to practice relaxation in other environments.

Treatment fidelity.

As reported in the primary outcome paper (Thorp et al., 2019), two clinicians trained in PE and RT rated each therapy session for 20% of veterans in this study (divided equally between PE and RT). Fidelity was rated by determining the average percentage of essential elements (e.g., imaginal exposure for PE, progressive muscle relaxation for RT) that were administered at each session (PE = 91.73%; RT = 88.00%; t(24) = 2.41, p = .20).

Treatment completion.

In the parent study, treatment completion and attrition rates did not statistically differ between PE and RT; 73% of veterans completed all 12 sessions of PE and 78% completed RT, (t[85] = −.049, p = 0.38).

Measures

The CAPS-IV (Blake et al., 1995), Posttraumatic Cognitions Inventory (PTCI; Foa et al., 1999), Posttraumatic Stress Disorders Checklist. Specific version (PCL-S; Weathers et al., 1993), and the Patient Health Questionnaire-9 (PHQ-9; Kroenke et al., 2001) were each administered at pretreatment, posttreatment, and 6-month follow-up

Posttraumatic Cognitions.

The PTCI (Foa et al., 1999) is a 33-item self-report measure used to assess the strength of negative cognitions following a traumatic event. Items are rated on a Likert-type scale (1 = totally disagree to 7 = totally agree), and ratings are summed to yield a total score. Total scores range from 33–231, with higher scores indicating stronger endorsement of negative cognitions. The PTCI contains three subscales: negative cognitions about the self (Self; “I am a weak person”; “My reactions since the event mean I am going crazy”), negative cognitions about the world (World; “People can’t be trusted”; “I can’t rely on other people”), and self-blame (Blame; “The event happened because of the way I acted”; “Somebody else would have stopped the event from happening”). The three subscales have been shown to have sound internal consistency among veterans: Self (α = .91), World (α = .79), and Blame (α = .70; Held et al., 2017). In this study, internal consistency was α = .95, α = .94, α = .88, and α = .85 for the total score, Self, World, and Blame subscales, respectively. The three-factor model has been validated (e.g., Andreu et al., 2016; Beck et al., 2004). The PTCI showed discriminant validity for the total, Self, and World subscales in prior studies (Beck et al., 2004).

Clinician-Assessed PTSD Symptom Severity.

The CAPS-IV is a gold-standard PTSD clinician-administered diagnostic assessment and was used to assess PTSD symptoms experienced in the past month. The Frequency (F1)/Intensity (I2; i.e., frequency ≥ 1, intensity ≥ 2) criteria was used to determine a current diagnosis (Weathers et al., 1999) and clinicians rated symptom items from zero (none) to four (extreme, incapacitating distress, cannot dismiss memories, unable to continue activities) for intensity and frequency (0 = never, 4 = daily or almost every day), which were summed to create a severity score. The severity scores range from 17–136, and higher scores indicate greater symptom severity. The CAPS-IV has demonstrated strong internal consistency (α = .84; Weathers et al., 2001), including in this study (α = .87).

Self-reported PTSD Symptom Severity.

The PCL-S (Weathers et al., 1993) is a commonly used self-report measure of PTSD symptoms related to an identified index trauma. The PCL-S has strong psychometric properties including test-retest reliability, and convergent and discriminant validity (Wilkins et al., 2011). Scores are rated on a one (not at all) to five (extremely) scale with total scores ranging from 17–85. Higher scores on the PCL-S indicate greater self-reported PTSD symptoms. Cronbach’s alpha in this sample was .89.

Self-reported Depression Symptom Severity.

Depressive symptom severity in the past two weeks was assessed using the PHQ-9 (Kroenke et al., 2001), a widely used self-report measure of depressive symptoms. The PHQ-9 consists of nine items that are rated from zero (not at all) to three (nearly every day); total scores range from 0–27 and greater scores signify greater depressive symptom severity. Internal consistency for the PHQ-9 in this sample was α = .87.

Data Analysis

All participants with PTCI subscale data from at least one assessment point were included in analyses. Multilevel modeling (MLM) in SPSS Statistics version 25 was used to examine whether PTCI total and subscale scores changed over the course of the study period (i.e., pretreatment, posttreatment, 6-month follow-up), and whether this change was predicted by treatment condition. Time, a quadratic growth function, treatment condition, and pretreatment PTSD and depressive symptom severity were included as main effects in the model.

Time consisted of three time points and was coded from 0 (intercept as pretreatment) through 2 (6-month follow-up). The quadratic growth function was calculated as the time value squared and was included based on previously published analyses demonstrating both linear and quadratic patterns of change in treatment outcomes (Thorp et al., 2019). Considering that the parent study was an RCT of PE (coded as 1) and RT (coded as 0), treatment condition was included in the model in order to account for the treatment conditions and to determine differences in posttraumatic cognitions differed by treatment condition. Pretreatment PTSD and depressive symptom severity were previously shown to differ between treatment conditions (Thorp et al., 2019) and are related to posttraumatic cognitions, so they were both added to the model. PTSD and depressive symptom severity are continuous variables and were mean centered for analyses. Model specifications were selected based on suitability for longitudinal designs and incorporated the restricted maximum likelihood (REML) approach for missing data, a random intercept, and an unstructured covariance structure.

Separate two-level MLM models were conducted for the PTCI total score and each of the three subscales. The first step of each model revealed whether there was significant variation across participants in both the intercept and random time slope. If significant variation was observed, then a second step was conducted that only included main effects. The final models consisted of the main effects, as well as the interactions between time and treatment condition to determine whether posttraumatic cognitions changed over time and if this change varied as a function of the type of treatment received. Tests of statistical significance were accompanied by within-group effect size indices (Cohen’s d calculated from complete data at assessment points, adapted for repeated measures), which are expressed as absolute values.

To explore the potential mediating role of posttreatment PTCI total scores on the effects of treatment assignment on treatment outcome, we tested three separate single mediator models of the primary treatment outcome symptom scores (i.e., CAPS-IV, PCL-S, and PHQ-9). We conducted all intervening variable models by using the process macro for bootstrapping (Preacher & Hayes, 2004) developed for use in SAS (SAS © software version 9.4; SAS Institute Inc, 2013). This procedure is designed to estimate effects of intervening variables. This procedure deletes cases listwise, so only cases with complete data were included in intervening variable models. As illustrated in Figure 1, bootstrapping mediation seeks to estimate the following three effects: 1) the direct effect of the treatment assignment on the outcome variable, which is independent of 2) the indirect effect of treatment assignment on outcome that is exerted via the mediator (i.e., posttreatment PTCI total score), and 3) the total effect of treatment assignment on the outcome variable, which is the sum of the direct effect and the indirect effect. The indirect effect provides an estimate of the effect of treatment on the outcomes that attributable to the mechanistic role of the proposed mediator. Bootstrapping models yield effect estimates, standard errors and 95% confidence intervals for the direct effect of the independent variable on the outcome variable, and the overall indirect effect of the independent on the variable via the mediating PTCI variable. We ran three models (each with n=10,000 resamples) with treatment condition as the independent variable, posttreatment PTCI total score as the intervening variable, and symptom severity total scores (i.e., CAPS-IV, PCL-S, and PHQ-9) at the 6-month follow-up as the outcome variables. All mediation models covaried the baseline PTCI total score and baseline value of the measure for which we were modeling the 6-month outcome score (i.e., CAPS-IV, PCL-S, PHQ-9).

Figure 1.

Figure 1.

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Means derived from complete data at each assessment time point. PTCI = Posttraumatic Cognitions Inventory. Sample sizes for means at pretreatment, posttreatment, and 6-month follow-up, respectively (PTCI Total Score: RT, n’s = 39, 32, 22; PE, n’s = 35, 23, 15; PTCI Self Subscale Score: RT, n’s = 39, 33, 22; PE, n’s = 37, 24, 16).

Results

PTCI Total Score Model.

Results from the first step of the PTCI total score model demonstrated significant variation in the intercept (B = 128.38, p < .001), linear time (B = −24.48, p = .05), and quadratic growth (B = 6.90, p = .03). MLM results from the final PTCI total score model are displayed in Table 1. In the final model, results showed a significant main effect of pretreatment depressive symptom severity as well as both interactions (i.e., time x treatment condition; quadratic growth x treatment condition). Study findings revealed that overall self-reported negative posttraumatic cognition scores tended to improve over time; however, the rate of change decelerated across the study period. The main effect of pretreatment depressive symptom severity indicates that older adult male veterans with higher pretreatment depressive symptom severity also had higher total scores on the PTCI across time. The interactions showed that veterans who received RT did not experience significant changes in overall posttraumatic cognitions from pre to posttreatment (d = 0.09; effect sizes adjusted for repeated measures) or from posttreatment to follow-up (d = −0.03); those who received PE reported significant improvement during the treatment period (d = −0.46; medium effect), but these gains were not maintained in the follow-up period, and actually worsened (d = 1.24; large effect; see Figure 1).

Table 1.

Between-Group Effects on Posttraumatic Cognitions

Parameter B SE t 95% CI
LB UB
PTCI Total Score
 Intercept 75.57 19.52 3.87*** 36.88 114.25
 Time −6.00 14.95 −0.40 −36.38 24.38
 Quadratic Growth 1.35 3.82 0.35 −6.41 9.11
 Pretreatment PTSD Severity (CAPS-IV) 0.22 0.27 0.82 −0.31 0.75
 Pretreatment Depression Severity (PHQ-9) 1.08 0.33 3.27** 0.42 1.74
 Treatment Condition 22.34 19.98 1.12 −17.81 62.49
 Time x Treatment Condition −52.52 22.71 −2.31* −98.62 −6.42
 Quadratic Growth x Treatment Condition 14.95 5.84 2.56* 3.13 26.78
PTCI Self Subscale
 Intercept 33.66 14.43 2.74** 10.67 66.64
 Time −2.53 10.71 −0.24 −24.15 19.07
 Quadratic Growth 0.22 2.74 0.08 −5.29 5.74
 Pretreatment PTSD Severity (CAPS-IV) .013 0.19 0.67 −0.26 0.51
 Pretreatment Depression Severity (PHQ-9) 0.78 0.24 3.25** 0.30 1.26
 Treatment Condition 24.48 14.15 1.73 −3.84 52.80
 Time x Treatment Condition −44.97 16.12 −2.79** −77.48 −12.45
 Quadratic Growth x Treatment Condition 12.78 4.12 3.10** 4.47 21.09
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Note: N = 86. Estimates of fixed effects reported.

*

p < .05,

**

p < .01,

***

p < .001. PTCI = Posttraumatic Cognitions Inventory. PTSD = Posttraumatic Stress Disorder. CAPS-IV = Clinician-Administered PTSD Scale. PHQ-9 = Patient Health Questionnaire, 9-Item. Treatment Condition was coded 0 (Relaxation Therapy), 1 (Prolonged Exposure); Time is a linear function and was coded as 0 (pretreatment), 1 (posttreatment), and 2 (6-month follow-up); Quadratic Growth is linear time squared.

PTCI Subscale Score Models.

The initial step of the PTCI subscale score models demonstrated that there was significant variation in the intercept (B = 80.11, p < .001), linear time (B = −18.64, p = .04), and quadratic growth (B = 4.99, p = .03) only for the Self subscale. Neither the World [intercept (B = 87.77, p < .001); linear time (B = −2.04, p = .52); and quadratic growth (B = 0.79, p = .32)] nor the Blame subscales [intercept (B = 15.06, p < .001), linear time (B = −4.38, p = .10), and quadratic growth (B = 1.26, p = .06) showed significant variation. As a result, final models were only conducted for the Self subscale.

The final model for the Self subscale revealed significant effects for pretreatment depressive symptom severity and the two interactions. Results indicated that PTCI Self subscale scores generally improved over time, the rate of change slowed across the study period, and veterans with higher pretreatment depressive symptom severity had more elevated Self subscale scores across assessment points. Similar to the results of the PTCI total score model, the Self subscale findings show a comparable pattern (see Figure 1) in which veterans randomized to RT did not experience significant changes in self-related posttraumatic cognitions from pre to posttreatment (d = 0.07) or from posttreatment to follow-up (d = −0.08), whereas those randomized to PE experienced significant changes while in active treatment (d = −0.60; medium effect), but self-related cognitions worsened in the follow-up period (d = 1.07; large effect).

Mediation Models.

See Figure 2 in the supplemental materials for a depiction of the intervening models that were conducted.

6-Month Follow-up CAPS-IV PTSD Symptoms.

In a model of the mediating role of posttreatment total PTCI on the effects of treatment condition on 6-month follow-up CAPS-IV PTSD symptoms, with baseline PTCI total and baseline CAPS-IV total covaried, there was not a statistically significant total effect of treatment condition on 6-month follow-up CAPS-IV PTSD symptoms (b = −3.61, SE = 5.27, 95% CI = −14.26, 7.03). There was also not a statistically significant direct effect of treatment condition on 6-month follow-up CAPS-IV PTSD symptoms (b = 3.50, SE = 5.05, 95% CI = −6.71, 13.72). However, there was a statistically significant overall indirect effect conveyed via the PTCI total (b = −7.12, SE = 3.10, 95% CI = −15.43, −2.49). The directions of this indirect were such that the PE group had significantly decreased posttreatment NPCs, and decreased posttraumatic cognitions were related to lower 6-month follow-up CAPS-IV PTSD symptoms.

6-Month Follow-up PCL-S PTSD Symptoms.

Similar to the pattern reported above for CAPS-IV, when modeling mediation of the 6-month follow-up PCL-S PTSD symptoms, there was no statistically significant total effect of treatment condition on 6-month follow-up PCL-S PTSD symptoms (b = 1.81, SE = 2.96, 95% CI = −4.17, 7.79) or direct effect of treatment condition on 6-month follow-up PCL-S PTSD symptoms (b = 3.88, SE = 3.07, 95% CI = −2.34, 10.10). However, there was a statistically significant overall indirect effect conveyed via the PTCI total (b = −2.07, SE = 1.45, 95% CI = −6.14, −0.06). The directions of this indirect were such that the PE group had significantly decreased posttreatment NPCs, and decreased posttraumatic cognitions were related to lower 6-month follow-up PCL-S PTSD symptoms.

6-Month Follow-up PHQ-9 Depressive Symptoms.

In a model of the mediating role of posttreatment total PTCI on the effects of treatment condition on 6-month follow-up depressive symptoms, with baseline PTCI total and baseline depressive symptoms covaried, There was also not a statistically significant total effect of treatment condition on 6-month follow-up depressive symptoms (b = 0.53, SE = 1.68, 95% CI = −2.88, 3.95) or a statistically significant direct effect of treatment condition on 6-month follow-up depressive symptoms (b = 1.69, SE = 1.69, 95% CI = −1.74, 5.12). However, there was a statistically significant overall indirect effect conveyed via the PTCI total (b = −1.15, SE = 0.90, 95% CI = −3.79, −0.002). The directions of this indirect were such that the PE group had significantly decreased posttreatment NPCs, and decreased posttraumatic cognitions were related to lower 6-month follow-up depressive symptoms.

Discussion

This study examined how NPCs change over time following PE and RT in a sample of older adult male veterans with military-related PTSD. We also looked at the intervening role of NPCs in PTSD and depressive symptoms changes from pretreatment to 6-month follow-up. Participants who received PE endorsed significant reductions in their overall posttraumatic cognitions and cognitions about the self during the active treatment period. The significant reductions from pre to posttreatment are consistent with other studies of PE (e.g., Foa & Rauch, 2004, Hagenaars et al., 2010), and suggest that overall negative cognitions and beliefs about the self can improve following PE even among older adult veterans. The similar patterns of change following PE for the overall score and the Self subscale may be due to the overlap between items in these two scales (i.e., 21 of the 33 total score items are Self subscale items). Additionally, participants with greater depressive symptom severity had higher PTCI total and Self scores across assessment time points, indicating that those with greater depressive symptoms have more elevated PTCI scores.

Despite significant reductions in the PTCI total score and the Self subscale from pre to posttreatment among those who received PE, these scores worsened through the follow-up period. One potential explanation for this rebound effect in NPCs may be that these veterans stopped or decreased their engagement in exposure when they no longer had the support of a therapist; therefore, opportunities to continue challenging posttraumatic cognitions and promote new learning through exposure may have decreased. Alternatively, because of the longstanding duration of NPCs in this population, older adult veterans may need additional sessions to maintain gains and continue to reinforce new beliefs acquired during therapy. Studies have started to evaluate variable length cognitive processing therapy (CPT; Galovski et al., 2012; Resick et al., 2016) and PE (Morland et al., 2020) because some individuals adequately respond to treatment early or require additional sessions beyond the standard protocol. Additional therapy sessions may also provide additional learning opportunities that are needed to address declines in cognitive flexibility.

The rebound effect for overall posttraumatic cognitions and negative beliefs about the self observed in this study is inconsistent with other PE studies with younger adult civilian samples that have shown maintenance of gains through follow-up (e.g., Foa & Rauch, 2004; Hagenaars et al., 2010). The difference in findings may be due to sample characteristics, which diverge in terms of both age and population. Additionally, Davison’s Late-Onset Stress Symptomatology (LOSS) model (Davison et al., 2006) proposes that veterans who have previously coped well with trauma may experience an increase in distress in older adulthood due to increased reminiscence triggered by stressful aging-related events (e.g., death of loved ones). This reminiscence, in combination with potentially more unstructured time due to not working in retirement, may lend itself to rumination about prior events. Nonetheless, this rebound effect is consistent with the self-reported PTSD symptom pattern from the larger parent study (Thorp et al., 2019), which found that self-reported PTSD symptoms significantly decreased from pre to posttreatment and then increased during the follow-up period. The extant literature clearly delineates a strong association between PTSD symptoms and posttraumatic cognitions (Schumm et al., 2015; Zalta et al., 2014); thus, the patterns of change over time are likely related. The increase in PTSD symptoms and negative cognitions from posttreatment to 6-month follow-up may have been further compounded by challenges in older adulthood, such as medical comorbidity, retirement, physical health concerns, and loss of partners or friends. Due to the attrition rate between posttreatment and 6-month follow-up, it is possible that the individuals who returned for follow-up were those in greater distress and may have returned for additional therapeutic support. These findings suggest that continued exposure practice following treatment, longer treatment duration, increased cognitive flexibility, or booster PE sessions may be necessary to maintain the beneficial improvements in posttraumatic cognitions that occur over the course of active treatment.

In contrast, and as expected, overall cognitions and posttraumatic cognitions about the self did not decrease following RT. The proposed mechanisms of change for RT (e.g., reductions in arousal, increased self-efficacy; Hayes-Skelton et al., 2015) may not modify maladaptive beliefs, as the techniques used in RT do not specifically target trauma-related cognitions. Based on these initial findings, RT may not be a recommended treatment approach for improving older adult veterans’ NPCs. However, if veterans or providers have concerns about the rebound effect found in this study, then a more general cognitive behavioral therapy may be appropriate (Clapp & Beck, 2012). If veterans have symptoms following RT, then they may consider PE. Other evidence-based PTSD treatment modalities, such as CPT, may also be helpful to reduce negative cognitions in older adults with PTSD. However, this remains an empirical question until studies are conducted to determine how well these treatments may work to address posttraumatic cognitions.

Unexpectedly, negative cognitions about the World and Blame did not significantly change over time for either PE or RT. These results are limited by the pretreatment differences between the PE and RT groups in the total NPCs, as well as World and Blame NPCs. This pretreatment difference arose by chance despite randomization, but could have influenced models of the change in NPCs over time. Because these analyses modeled trajectories, the significant differences between treatment groups at pretreatment was taken into account in analyses, though the chance pretreatment difference makes complicates interpretation of effects on NPCs. The lack of change in these subscales following PE is inconsistent with prior PE studies with younger civilian samples (e.g., Foa & Rauch, 2004; Hagenaars et al., 2010). Differences in findings between the studies may be due to the different trauma populations (i.e., veterans vs. civilians) and time since the traumatic event. It is possible that negative beliefs about the world are more difficult to disconfirm and require more evidence, and a lack of control over others’ behaviors may make these beliefs more resistant to change without significant exposure-based “testing.” This additional testing through exposure could have stopped when PE ended, leaving these older adults with their original, familiar social interactions. This is consistent with Socioemotional Selectivity Theory, which theorizes that older adults closer to the end of life tend to interact with familiar individuals and often have smaller social circles due to seeking out new relationships less often (Carstensen, 1995). Therefore, individuals may have had fewer opportunities to disconfirm negative beliefs about the world and others and fewer opportunities to receive corrective information from others about their self-blame. Since the breadth of social interactions to provide disconfirming evidence could be narrower in older adults, it is possible they would benefit more from treatments such as Cognitive Processing Therapy, which focus on skills that can practiced in solitude or within smaller social groups. Self-blame has also previously been found to be a residual PTSD symptom following evidence-based PTSD treatments (Larsen et al., 2019). Older adult veterans who blame themselves for the traumatic event may need a longer treatment duration to specifically target erroneous self-blame, or may benefit from more targeted techniques, such as cognitive restructuring. The Blame subscale has been found to have poorer psychometrics compared to the other PTCI subscales in prior studies (e.g., Beck et al., 2004), which may partially account for the nonsignificant changes in this subscale; however, the Blame subscale had adequate internal consistency in our study.

In addition to changes in posttraumatic cognitions over time, this study evaluated models of the intervening effects of NPCs on symptom outcomes. Results demonstrated that changes in PTCI total scores performed in a way that is consistent with their conceptual role as treatment mechanisms. Specifically, PE conveyed treatment effects on decreased 6-month follow-up clinician-administered symptoms via PTCI total scores that were decreased after covarying the relevant baseline PTCI and CAPS scores. This finding highlights the importance of reducing overall posttraumatic cognitions during treatment. These findings highlight of importance of reducing posttraumatic cognitions during PE in older adult veterans. However, NPCs did not convey a significant intervening effect of PE on 6-month follow-up for depressive symptom severity.

While there was a rebound in NPCs from posttreatment to 6-month follow-up, our analyses suggest that posttreatment NPCs serve as an effective mechanism for conveying effects of PE on longer-term clinician-administered and self-reported PTSD symptoms in older veterans. Although there was not a total effect of treatment on clinician-administered or self-reported PTSD symptoms, it is still possible to observe overall indirect effects via a treatment mechanism because direct effects of treatment on longer-term outcome could be in the opposite direction of the indirect effect (Zhao et al., 2010), as we observed in the current study. Placed within the context of the overall trial, the rebound effect on self-reported PTSD symptoms may be due to limited changes in NPCs, specifically cognitions related to blame and negative beliefs about the world. Additionally, the rebound effect for self-reported PTSD symptoms in the parent trial may be partially attributed to PTCI total and Self scores increasing from posttreatment to 6-month follow-up. These results suggest that clinicians working with older veterans might consider measuring and attending to persistent NPCs at the mid-treatment point, as they could be an indicator that veterans are at risk for a resurgence of symptoms following treatment.

The current study is the first, to our knowledge, to evaluate the impact of PE on older adult veterans’ posttraumatic cognitions compared to an active comparator. Strengths of this study include the use of a rigorous RCT design and analytic approaches well-suited to analyze longitudinal data. Study data were collected from both gold-standard clinical interviews and validated self-report measures. This study also has limitations. The PTCI was not administered weekly or at mid-treatment, so the pattern of change in cognitions during treatment sessions could not be determined. Furthermore, it was not possible to evaluate the temporal sequence of cognitive change in relation to PTSD or depressive symptom change during therapy. The PE group also had greater fidelity ratings compared to RT, which may have had an impact on treatment; however, this difference was not statistically significant. Notably, the sample consisted of only older adult male veterans, so findings may not generalize to other populations, such as women, younger veterans, and civilians. The sample size was also relatively small for an RCT and may have minimized the ability to detect significant differences. Finally, there was a significant difference for pretreatment PTCI scores between PE and RT, which is also a limitation.

Despite the limitations, this study highlights important findings suggesting that PE can significantly reduce overall negative beliefs and cognitions about the self during active treatment, but that additional exposure practice, booster PE sessions, or a longer treatment duration may be needed to sustain these improvements following treatment. In contrast, RT may not be a sufficient treatment modality to decrease NPCs given that cognitions remained stable across time and did not significantly improve for those who received RT. Based on the limited data available for older adult male veterans, we preliminarily recommend PE over RT for specifically reducing NPCs given the significant reductions during active treatment; however, it is critically important to determine how to maintain therapeutic gains following treatment. Fortunately, lower overall negative cognitions and negative cognitions of the self at posttreatment were associated with lower clinician-rated PTSD and self-reported PTSD symptoms six months later. This emphasizes the importance of reducing NPCs as much as possible during PE. Future research should examine the pattern of posttraumatic belief symptom change in older veterans with PTSD, how it relates to symptom change, and determine the best approach to maintaining change in negative cognitions across time.

Supplementary Material

Supplemental Material

Clinical Impact Statement.

Prolonged exposure therapy (PE) can significantly improve overall negative posttraumatic cognitions and negative cognitions about the self in older veterans with PTSD but these gains are not maintained six months after PE. Booster sessions or longer treatment duration may be helpful to maintain gains. Relaxation therapy is not recommended to improve negative posttraumatic cognitions in older veterans.

Acknowledgements:

This work is partially supported by a Career Development Award (CDA-2-009-07S) that was awarded to Dr. Thorp by the Department of Veterans Affairs. Dr. Dedert was supported by Merit Review Award Number I01 CX001757-01A2 from the United States (U.S.) Department of Veterans Affairs Clinical Sciences R&D (CSRD) Service. Dr. Dedert was also supported by the National Evidence-Based Psychotherapy Training Program, Department of Veterans Affairs Office of Mental Health and Suicide Prevention.

Footnotes

The authors disclose no conflicts of interest.

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