Reduced Symptoms of Post-Traumatic Stress Disorder and Irritable Bowel Syndrome Following Mindfulness-Based Stress Reduction Among Veterans

Abstract

Objectives:

Post-traumatic stress disorder (PTSD) and irritable bowel syndrome (IBS) are highly comorbid conditions associated with reduced health-related quality of life. Comorbid prevalence is especially high among veterans, ranging from 23% to 51%, but there is limited research on integrative treatments.

Design:

To improve treatment of comorbid PTSD and IBS, this study examined the impact of mindfulness-based stress reduction (MBSR) on symptom reduction and mindfulness skill building among veterans with this comorbidity. We hypothesized that veterans would report reduced trauma-related, gastrointestinal (GI) symptom-specific anxiety (GSA), and depression symptoms and greater mindfulness skills post-treatment. We also hypothesized that veterans who reported lower trauma-related GSA and depression symptoms, and reported greater mindfulness skills and MBSR session attendance would report lower irritable bowel symptoms post-treatment.

Settings/Location:

VA (Veterans Administration) Puget Sound Health Care System, Seattle, Washington.

Subjects:

Participants were 55 veterans with PTSD and IBS.

Interventions:

Veterans participated in an 8-week open trial of MBSR group.

Outcome measures:

This study measured the impact of MBSR on PTSD, IBS, GSA, and depression symptoms as well as mindfulness skills.

Results:

Veterans reported reduced trauma-related, irritable bowel, GSA, and depression symptoms and greater mindfulness skills immediately post-treatment. Trauma-related and depression symptom reduction were maintained 4 months post-treatment, but irritable bowel and GSA symptoms were nonsignificant. Lower baseline GSA predicted lower irritable bowel symptoms immediately post-treatment. At 4 months post-treatment, 77.50% met PTSD criteria and 40.38% met IBS criteria compared with 100% veteran comorbidity pretreatment.

Conclusions:

MBSR holds promise as a transdiagnostic intervention for individuals with comorbid trauma-related, depression, GSA, and irritable bowel symptoms, with maintenance of trauma-related and depression symptom improvement 4 months post-treatment.

Introduction

Post-traumatic Stress Disorder (PTSD) is a common condition in the United States general population with an estimated at 8.3% lifetime prevalence.¹ There is growing evidence that trauma-related symptoms are associated with an increased likelihood of developing symptom-based syndromes without identifiable physical causes, such as irritable bowel syndrome (IBS),^2

–5 which is characterized by chronic abdominal pain or discomfort.⁶ An estimated 14.1% of the United States meets diagnostic criteria for IBS within a 12-month period,⁷ and IBS is the most frequent reason for a gastroenterologist visit (19% of all referrals).⁸ IBS patients attend more nongastrointestinal (non-GI) healthcare visits and incur twice the healthcare costs compared with controls, likely stemming from high rates of psychiatric disorders, such as major depressive disorder and non-GI somatic syndromes, such as fibromyalgia, chronic fatigue syndrome, temporomandibular joint disorder, and chronic pelvic pain.⁹

PTSD and IBS are often comorbid,¹⁰ especially among military veterans.^11,12 In a study of 603,221 Iraq and Afghanistan veterans, IBS risk progressively rose as the number of mental health diagnoses rose, with GI disorder–PTSD comorbidity at 23% among males and females.¹² Similarly, a large study of women veterans recruited from a Veterans Administration (VA) primary care setting demonstrated that 51% of female veterans with IBS screened positive for PTSD, whereas 31% of those without IBS screened positive for PTSD.¹¹

Pathways to comorbidity

The pathway between PTSD and IBS is conceptualized as resulting from both psychological and physiological factors.^9,13 Physiologically, IBS is postulated to result from dysregulation of the enteric nervous system due to persistent activation of the body's stress response, which has been termed allostatic load.¹⁴ According to this framework, allostatic load accumulates through stressful event exposure, with greater chronic stress strongly predicting earlier onset, greater severity, and reduced treatment responsiveness of IBS.^15,16 Allostatic load theory specific to IBS postulates dysregulation in hypothalamic–pituitary–adrenal axis activity, greater perceptual sensitivity toward internal sensations, and elevated baseline stress reactivity.¹⁷ For individuals with PTSD and IBS, chronic stress, and hyperarousal due to trauma exposure are hypothesized to trigger sympathetic nervous system responses that cause altered GI motility and symptoms (cramping and pain).^15,16 In turn, altered motility and pain are postulated to increase vagal afferent input from the enteric nervous system to the central nervous system (CNS), which results in a positive-feedback cycle involving GI symptoms and CNS arousal.¹³

In addition to physiological mechanisms, GI symptom-specific anxiety (GSA) has been proposed as a key psychological mechanism to explain the maintenance and development of PTSD–IBS comorbidity.¹⁸ GSA describes anxiety resulting from GI symptoms and the contexts in which they occur, which can include hypervigilance, fear, worry, and avoidance of GI sensations and situations involving food and eating.^19,20 GSA also can include beliefs about inability to control symptoms, which can contribute to reduced quality of life reported in IBS patients.²¹ Like GSA, PTSD also is commonly associated with hypervigilance, increased anxiety, increased focus on internal sensations such as GI symptoms,^20,22 and greater perceived relevance of GI sensations. Hence, GSA may represent a chronic stressor¹⁷ that disrupts adaptive GI functioning through alterations in CNS functioning and related cognitive mechanisms.^20,22

PTSD–IBS treatment

Given the importance of mental health conditions, particularly PTSD, as risk factors for IBS among veterans,^11,12 treatments targeting stress reduction may concurrently treat both conditions. Mindfulness-based interventions are shown to improve PTSD symptoms^23
–25 and IBS.^26,27 In particular, mindfulness-based stress reduction (MBSR)²⁸ is an empirically supported intervention that is demonstrated to reduce depression, suicidal ideation, anxiety, and PTSD symptoms among veterans^25,29 and reduce IBS symptoms among civilians.^26,30 Despite growing support for the healing capacity of MBSR, no research has examined the impact of MBSR on comorbid PTSD and IBS among veterans.

Despite literature indicating a relationship between PTSD and IBS, to date, there is little research on integrative treatment approaches for individuals with PTSD and IBS.¹² Optimal treatment approaches for individuals with IBS would address both mental health conditions and physical symptomatology to potentially benefit individuals across conditions. Hence, additional studies examining integrative treatment approaches for IBS and psychiatric comorbidity, such as PTSD and depression, are needed to provide a better understanding of how mental and physical health conditions respond to intervention.

Current Study

To address the need to better understand and treat comorbid PTSD–IBS among veterans, the current study examined the impact of an 8-week open trial of MBSR on symptom reduction and mindfulness skill building among veterans with both conditions. First, we hypothesized that veterans would report reductions in PTSD, IBS, GSA, and depression symptoms as well as greater mindfulness skills immediately post-MBSR and 4 months post-MBSR as compared with baseline. We also examined the impact of MBSR on depression symptoms given the high prevalence of depression in both PTSD and IBS,³¹ and we examined whether there were changes in the proportion meeting Rome III IBS criteria at each time point. Second, we hypothesized that veterans who reported lower baseline PTSD, GSA, and depression symptoms and reported greater baseline mindfulness skills and attended more MBSR sessions would report lower IBS symptoms post-MBSR.

Materials and Methods

Participants and procedure

Participants were 55 veterans with PTSD and IBS who participated in MBSR at the VA Puget Sound Health Care System and completed assessments at pre-MBSR baseline, immediately post-MBSR, and 4 months post-MBSR. Veterans were 85.5% male with a mean age of 52.55 years (standard deviation [SD] = 11.68 years). Culturally, 83.6% of veterans identified as Caucasian, 9.1% identified as African American, 1.8% identified as Hispanic, 1.8% identified as Asian/Pacific/Native American, and 3.6% identified as another cultural background. Veterans attended an average of 6.31 sessions (SD = 2.60) and 29.1% of veterans attended all 9 sessions (eight 2.5-h weekly groups and a Saturday 7-h retreat between weeks 6 and 7). Study data represent an aggregate of three MBSR trials, with veterans from the first trial participating in MBSR as clinically indicated and the second and third trials conducted as randomized controlled pilot studies of MBSR compared with treatment as usual. For all trials, exclusion criteria included (1) a history of a psychotic disorder; (2) mania, or poorly controlled bipolar disorder; (3) known borderline or antisocial personality disorder; (4) current suicidal or homicidal ideation with intent; and (5) active substance use disorder. Only veterans who met a symptom cutoff score for PTSD (see the Measures section for details) and who met criteria for IBS at baseline assessment were included in analyses. Veterans were recruited through VA provider referral, provided informed consent, and voluntarily participated without monetary compensation.

Measures

Post-traumatic stress disorder

PTSD symptom severity was measured with the 17-item PTSD Checklist—Civilian Version (PCL-C)³² for DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition). Veterans rated to what extent they were bothered by each symptom over the past month from 1 (not at all) to 5 (extremely) for items such as, “Feeling very upset when something reminded you of a stressful experience from the past?” Higher scores represented greater PTSD symptom severity. The PCL-C demonstrated strong internal consistency (α = 0.96)^33,34 and convergent validity with the Clinician-Administered PTSD Scale (r = 0.79)³³ in veteran samples, and Cronbach's α = 0.89 in our study. We adhered to the recommended cutoff score of 36³² to determine PTSD sample prevalence.

IBS diagnostic status

Symptom-based diagnostic criteria for IBS was defined by having subjects complete a written version of the Rome III questionnaire.⁶ The Rome III questionnaire asks if a person has recurrent abdominal pain or discomfort at least 3 days per month over the last 3 months and is associated with two or more of the following: improvement with defecation, onset associated with a change in frequency of stool, onset associated with a change in form (appearance) of stool. The diagnosis of IBS was based on Rome III diagnostic criteria.

IBS symptom severity

IBS symptom severity was measured with the 4-item Irritable Bowel Severity Scoring System (IBS-SSS).³⁵ Veterans rated to what extent they experienced each symptom over the past 10 days from 0 (no symptom distress) to 100 (extreme symptom distress) for items such as, “how severe is your abdominal distension/tightness.” Higher scores represented greater IBS symptom severity. In a psychometric comparison of IBS outcome measures, the IBS-SSS was evaluated as the strongest instrument.³⁶ Cronbach's α = 0.83 in our study.

GI symptom-specific anxiety

GSA was measured with the 15-item Visceral Sensitivity Index (VSI).³⁷ Veterans rated to what extent they experienced each symptom over the past week from 1 (strongly agree) to 6 (strongly disagree) for items such as, “I often worry about problems in my belly.” Items were reverse scored so that higher scores represented greater GI-specific anxiety. The VSI demonstrated strong discriminant validity with the Hospital Anxiety and Depression Scale and the Anxiety Sensitivity Index in a sample of IBS patients.³⁷ The VSI also demonstrated strong reliability (α = 0.93) in a sample of adults with a history of IBS, and α = 0.95 in our study.

Depression

Depression symptoms were measured with the Patient Health Questionnaire 9-Item Depression Scale (PHQ-9)³⁸ or the Patient-Reported Outcomes Measurement Information System (PROMIS).³⁹ Both measures were converted to a single comparable metric using the guidelines provided by the NIH-sponsored PROsetta Stone Project⁴⁰ for transforming PROMIS T-score values into PHQ-9 raw scores. Veterans rated to what extent they were bothered by each symptom over the past 2 weeks from 0 (not at all) to 3 (nearly every day) for items such as, “Little interest or pleasure in doing things.” Higher scores represented greater depression symptom severity. The PHQ-9 demonstrated strong internal consistency (α = 0.86–0.89) and test–retest reliability (r = 0.84–0.95) in a civilian medical sample, and α = 0.88 in our study.

Mindfulness skills

Mindfulness skills were measured with the 39-item Five Facet Mindfulness Questionnaire (FFMQ).⁴¹ The FFMQ includes five psychometrically distinct subscales: observing, describing, acting with awareness, nonjudging of inner experience, and nonreactivity to inner experience. The FFMQ observing subscale was excluded in regression analyses as recommended by Gu et al.,⁴² since the factor structure of the FFMQ is better represented when observing is excluded from the multifaceted construct of mindfulness. Higher scores represented greater mindfulness skills for each facet. The FFMQ demonstrated strong internal consistency (α = 0.77–0.93) and construct validity in a civilian adult sample, and α = 0.79 in our study.

Data analytic plan

Missing data analyses in SPSS indicated that data were missing nonrandomly at baseline (χ²[38] = 53.57, p = 0.048) due to 19 veterans not completing the baseline IBS symptoms measure, but other data were missing completely at random (MCAR) immediately post-MBSR (χ²[18] = 27.97, p = 0.062) and 4 months post-MBSR (χ²[27] = 35.15, p = 0.135) as determined by Little's MCAR test. In Table 1, variable correlations between health comorbidities and mindfulness skill facets were examined across time points with two-tailed significance. In Table 2, baseline and post-MBSR score differences were examined with paired-samples t-tests, with the magnitude of effects represented by Cohen's d statistics. In Table 3, baseline predictors of post-MBSR IBS symptom severity were examined with linear regression with all variables entered into the same model. Six veterans were excluded from analyses due to not attending any MBSR sessions after completing baseline assessment, and an additional 7 veterans were excluded from analyses due to reporting subthreshold PTSD symptoms as determined by the PCL-C,³² resulting in the final sample size of 55 veterans with comorbid PTSD and IBS. Changes in IBS diagnostic status also were examined with McNemar's test,⁴³ which offers a repeated measures alternative to a χ² test by calculating consistency in IBS diagnostic status across time points.

Table 1.

Variable Correlations Between Health Comorbidities and Mindfulness Skill Facets

	1	2	3	4	5	6	7	8	9	10	11	M (SD)
Baseline
1. IBS												255.46 (97.50)
2. PTSD	0.21											57.56 (10.58)
3. Depression	0.48^**	0.56^**										15.29 (6.12)
4. GSA	0.68^**	0.35	0.31^*									32.20 (20.05)
5. Describing	−0.14	−0.03	−0.03	0.05								22.75 (8.13)
6. Acting	−0.01	−0.41^**	−0.43^**	−0.13	0.30^*							21.22 (6.20)
7. Nonjudging	−0.12	−0.23	−0.31^*	−0.40^**	0.10	0.31^*						21.22 (6.69)
8. Nonreactivity	−0.18	−0.06	−0.20	−0.12	0.27^*	0.16	0.19					17.60 (4.83)
Post
9. IBS	0.88^***	0.31	0.49^*	0.62^**	0.00	−0.11	−0.14	−0.10				231.35 (121.95)
10. PTSD	0.37^*	0.69^***	0.47^**	0.40^*	0.01	−0.32^*	−0.26	0.04	0.55^**			50.37 (15.41)
4 Months post
11. IBS	0.85^**	−0.13	0.24	0.50^*	−0.40	0.05	−0.03	−0.22	0.71^**	−0.02		212.16 (111.31)
12. PTSD	0.33	0.62^***	0.42^**	0.40^**	0.07	−0.44^**	−0.30	−0.03	0.39	0.81^***	0.20	50.10 (15.81)

p < 0.05, ^** p < 0.01, ^*** p < 0.001.

Acting, acting with awareness; GSA, gastrointestinal symptom-specific anxiety; IBS, irritable bowel syndrome; PTSD, post-traumatic stress disorder; SD, standard deviation.

Table 2.

Changes in Symptom Severity and Mindfulness Skills Over Time

	Baseline to immediately post-MBSR			Baseline to 4 months post-MBSR			Immediately post-MBSR to 4 months post-MBSR
	n	M (SD)	d	n	M (SD)	d	n	M (SD)	d
IBS	23	−22.22 (60.61)^**	0.19	15	−33.87 (65.20)	0.30	15	−10.60 (90.04)	0.09
PTSD	46	−7.63 (11.18)^***	0.19	40	−7.03 (12.46)^**	0.52	38	−0.84 (9.92)	0.05
Depression	45	−3.27 (6.09)^**	0.50	39	−3.05 (5.28)^**	0.44	37	−0.05 (4.99)	0.01
GSA	46	−6.63 (20.43)^*	0.32	40	−4.30 (16.70)	0.20	38	0.97 (17.40)	0.04
Mindfulness
Describing	46	3.02 (5.35)^***	0.40	40	2.70 (6.74)^*	0.35	38	−0.32 (5.91)	0.04
Acting	46	2.59 (7.24)^*	0.37	40	4.40 (5.77)^***	0.64	38	1.55 (6.91)	0.21
Nonjudging	46	4.00 (7.98)^**	0.50	40	4.00 (7.33)^**	0.53	38	−0.45 (6.04)	0.05
Nonreactivity	46	3.35 (5.88)^***	0.60	40	2.85 (6.24)^**	0.50	38	−0.42 (4.02)	0.07

p < 0.05, ^** p < 0.01, ^*** p < 0.001.

Acting, acting with awareness; GSA, gastrointestinal symptom-specific anxiety; IBS, irritable bowel syndrome; MBSR, mindfulness-based stress reduction; PTSD, post-traumatic stress disorder; SD, standard deviation.

Table 3.

Baseline Predictors of Irritable Bowel Syndrome Symptom Severity Over Time

	Immediately post-MBSR (IBS n = 26)		4 Months post-MBSR (IBS n = 19)
	b (SE)	p	b (SE)	p
Age, n = 55	−1.32 (2.45)	0.60	−2.22 (3.48)	0.54
Gender, n = 55	−14.80 (51.80)	0.78	−46.91 (96.04)	0.64
Attendance, n = 55	−10.15 (15.68)	0.53	3.13 (13.30)	0.82
PTSD, n = 55	−1.11 (2.76)	0.69	−4.06 (3.14)	0.23
Depression, n = 55	7.23 (4.29)	0.12	5.17 (4.83)	0.32
GSA, n = 55	3.61 (1.34)	0.017	4.27 (2.33)	0.11
Mindfulness
Describing, n = 46	−1.36 (3.94)	0.74	−3.07 (4.98)	0.55
Acting, n = 46	0.91 (4.55)	0.84	5.17 (4.91)	0.32
Nonjudging, n = 46	0.12 (4.35)	0.98	−0.95 (6.37)	0.89
Nonreactivity, n = 46	−1.61 (5.40)	0.77	−6.76 (5.90)	0.29

Bold values indicate statistically significant effects.

Acting, acting with awareness; GSA, gastrointestinal symptom-specific anxiety; IBS, irritable bowel syndrome; MBSR, mindfulness-based stress reduction; PTSD, post-traumatic stress disorder.

Results

Regarding correlations (Table 1), baseline mindfulness skills were not significantly associated with IBS symptoms at any time point. PTSD symptoms were negatively associated with the concurrent mindfulness facet of acting with awareness immediately post-MBSR and 4 months post-MBSR. Baseline depression symptoms were negatively associated with the concurrent mindfulness facets of acting with awareness and nonjudging. Baseline GSA was significantly correlated with IBS at all time points, and baseline GSA was associated with PTSD immediately post-MBSR and 4 months post-MBSR. PTSD symptoms immediately post-MBSR and baseline IBS symptoms were significantly associated, but PTSD and IBS were not otherwise associated.

Changes in symptom severity and mindfulness skills from baseline to immediately post-MBSR (i.e., 2 months after baseline assessment) and 4 months post-MBSR (i.e., 6 months after baseline assessment) are reported in Table 2. Consistent with hypotheses, veterans reported significantly lower PTSD, IBS, GSA, and depression symptoms with small to medium effect sizes post-MBSR but not at 4-month follow-up. Partially consistent with the hypothesis, veterans reported significantly lower PTSD and depression symptoms 4 months post-MBSR. Veterans also reported greater mindfulness skills across all four facets immediately post-MBSR and 4 months post-MBSR compared with baseline assessment. No symptoms or mindfulness skills significantly changed from immediately post-MBSR to 4 months post-MBSR, indicating that treatment gains were maintained several months after treatment completion. Partially consistent with hypotheses, lower baseline GSA symptoms predicted lower IBS symptoms immediately post-MBSR, whereas age, gender, attendance, PTSD, depression, and mindfulness skills did not (Table 3). IBS symptoms 4 months post-MBSR was not uniquely associated with any variables.

Regarding PTSD prevalence, 55/55 of veterans reported PTSD symptoms at or above the clinical cutoff for PTSD based on the PCL-C at baseline, 36/46 (78.26% with 9 missing values) reported clinically significant PTSD symptoms immediately post-MBSR, and 31/40 (77.50% with 15 missing values) reported PTSD symptoms above the recommended clinical cutoff value 4 months post-MBSR. Based on McNemar's test, significantly fewer veterans met criteria for PTSD immediately post-MBSR (χ² = 8.10, p = 0.004) and 4 months post-MBSR (χ² = 7.11, p = 0.008) compared with baseline. In addition, veterans maintained their absence of PTSD diagnostic status from immediately post-MBSR to 4 months post-MBSR (χ² = 0.25, p = 0.617).

Regarding IBS prevalence, 55/55 (100%) of veterans met diagnostic criteria for IBS at baseline (based on the Rome III questionnaire), 30/53 (56.60% with two missing values) met criteria immediately post-MBSR, and 21/52 (40.38% with three missing values) met criteria 4 months post-MBSR. All veterans were initially diagnosed with IBS, so changes in diagnostic status represented GI symptom reduction to an extent that they no longer met IBS diagnostic criteria. Based on McNemar's test, significantly fewer veterans met criteria for IBS immediately post-MBSR (χ² = 21.04, p < 0.001) and 4 months post-MBSR (χ² = 29.03, p < 0.001) compared with baseline. In addition, veterans maintained their absence of IBS diagnostic status from immediately post-MBSR to 4 months post-MBSR (χ² = 3.06, p = 0.080).

Discussion

PTSD symptom reduction was consistent with a prior randomized controlled trial of MBSR for combat veterans with PTSD, which showed greater reductions in PTSD symptoms for those randomized to MBSR as compared with an active control.²⁵ IBS symptom reductions also were consistent with a randomized controlled trial of MBSR as compared with an active control for IBS,²⁷ although that trial was limited to civilian women. Depression symptom reductions also were consistent with a broader literature indicating beneficial effects of mindfulness-based interventions on depression.⁴⁴ Findings build on a prior report from our research group on MBSR⁴⁵ by exclusively examining veterans with comorbid PTSD–IBS and incorporating a larger sample size. Lastly, findings corroborate previous literature²¹ by demonstrating that GSA uniquely predicts IBS symptom reduction, even when controlling for comorbid depression and PTSD symptoms.

While PTSD and IBS symptoms both declined after participation in MBSR, only PTSD immediately post-MBSR and baseline IBS were significantly associated. Additionally, PTSD and GSA were not significantly associated. A potential explanation for this lack of association is a true lack of association between these symptom categories.⁴ Another reason for nonsignificance may be the relatively small sample size, which may have limited our power to detect significant effects, although we did find robust correlations between IBS and depression symptoms. For example, IBS symptoms significantly decreased from baseline to immediately post-MBSR with n = 23, but the limited n = 15 for IBS symptoms 4 months post-MBSR did not detect significance despite larger regression coefficients and effect sizes compared with the significant baseline to immediately post-MBSR results with a larger n. The lack of association between PTSD and IBS suggests that MBSR may reduce symptoms for each of these syndromes through distinct mechanisms. Other researchers have posited that comorbidity between PTSD and functional somatic syndromes such as IBS may be explained by shared mechanisms, such as perseverative focus on ambiguous physical symptoms with an inclination toward interpreting symptoms as threatening and high sensitivity to anxiety,² but further research is warranted to clarify relationships between PTSD–IBS symptoms and depression–IBS symptoms.

Findings should be considered in the context of study limitations and future directions. This uncontrolled self-report study does not allow conclusions regarding a causal association between MBSR participation and the observed results. Due to the absence of a control group for this sample, we could not determine whether symptom changes represented regression to the mean or a significant improvement due to the study intervention. Comorbid mental health conditions that were not directly examined (e.g., somatic symptom disorders) and broader group variables (e.g., group social support, behavioral activation) also may have impacted veteran MBSR responses. In addition, the relatively small sample size limited our power to detect significant effects and did not allow sufficient power to conduct mediation analyses. This small sample size was partially due to 19 veterans not completing the baseline IBS symptoms measure but completing the remaining measures.

Future research is needed to better understand the mechanisms underlying PTSD–IBS comorbidity, which might allow interventions to target key factors involved in the maintenance of both conditions. Future investigations could include expanding the development and implementation of comorbid treatments, such as cognitive therapy that targets anxiety and physical sensations across both conditions. Cognitive therapy is supported to reduce PTSD^23,46 and IBS⁴⁷ separately, so future research may consider ways to tailor cognitive therapies to address both symptom clusters. MBSR represents only one treatment option for PTSD–IBS comorbidity, and our study provides initial support for the clinical application of MBSR for veterans with this comorbidity. A case study demonstrated that treating PTSD symptoms first may contribute to an improvement in depression, panic, and IBS symptoms concurrently.⁴⁸ However, group-based empirical research is needed to generalize this study to veteran populations.

Conclusions

Veterans with PTSD and IBS who participated in MBSR reported reductions in IBS, PTSD, depression, and GSA symptoms, with small to medium effect sizes. While veterans still reported IBS symptoms following participation in MBSR, the majority no longer met diagnostic criteria for IBS at 4-month follow-up. Findings also suggest that GSA plays a key role in IBS symptomatology, as lower GSA predicted lower IBS symptoms immediately post-MBSR in our data. Overall, this study provides initial support for MBSR as a potential transdiagnostic intervention for veterans with comorbid PTSD and IBS and supports the need for randomized controlled trials to further assess the impact of MBSR on PTSD and IBS symptoms.

Footnotes

Acknowledgments

None declared.

Author Disclosure Statement

No competing financial interests exist.

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