Intensive prolonged exposure therapy for chronic PTSD patients following multiple trauma and multiple treatment attempts

Figures & data

Figure 1. Flow diagram of patient recruitment and trial progress.

Note: CAPS-IV = Clinician-Administered PTSD Scale; EAS = euthanasia or assisted suicide; iPE = intensive prolonged exposure; mo = month; PTSD = posttraumatic stress disorder.

Table 1. Characteristics of the study population (N = 73).

Characteristics
Age in years, mean (SD), range	35.9 (11.3), 19–63
Sex, n
Male	10
Female	63
Education, n (%)
Primary education	0 (0.0)
Secondary education	18 (24.7)
Vocational education	24 (32.9)
Higher vocational education	25 (34.2)
University	6 (8.2)
Living condition, n (%)
Alone	31 (42.5)
Together	42 (57.5)
Trauma history, n (%)
Childhood, ≤ 16 years
Multiple sexual abuse	52 (71.2)
Multiple physical abuse	46 (63.0)
Adulthood, > 16 years
Multiple sexual abuse	31 (42.5)
Multiple physical abuse	42 (57.5)
Time since trauma in years, mean (SD), range	28.2 (12.0), 6–59
Current medium or high suicide risk, n (%)	33 (48.5) ^a
CAPS-IV baseline, mean (SD), range	85.1 (17.2), 41–128
PSS-SR baseline, mean (SD), range	33.3 (6.5), 18–46 ^b
BDI-II baseline, mean (SD), range	30.6 (11.1), 0–51 ^b
DES baseline, mean (SD), range	22.7 (13.3), 0–56 ^c
DES baseline, score above clinical cut-off ^d, n (%)	20 (32.8) ^c
BPD-47 baseline, mean (SD), range	103.7 (27.2), 51–203 ^b
BPD-47 subscales baseline, mean (SD), range
Affect dysregulation ^e	32.3 (9.0), 19–64 ^b
Negative self-concept ^f	20.1 (6.0), 8–36 ^b
Interpersonal problems ^g	7.4 (3.1), 3–15 ^b
Axis I and II comorbidity (current), n (%)	68 (93.2)
1–2 comorbid disorder	45 (61.6)
≥ 3 comorbid disorders	23 (31.5)
Comorbid depressive disorder, n (%)	50 (68.5)
At least one comorbid anxiety disorder, n (%)	23 (31.5)
At least one comorbid personality disorder, n (%)	35 (47.9)
Receiving psychotropic medication, n (%)	56 (76.7)
Duration of PTSD in years, mean (SD), range	10.6 (9.7), 1–40

Note: BDI-II = Beck Depression Inventory Second Edition; BPD-47 = Borderline Personality Disorder Checklist; CAPS-IV = Clinician-Administered PTSD Scale; DES = Dissociative Experiences Scale; PSS-SR = PTSD Symptom Scale, Self-Report; PTSD = posttraumatic stress disorder.

^a N = 68

^b N = 69

^c N = 61

^d Clinical cut-off defined as a DES severity score of 25 (Boon & Draijer, 1993).

^e Sum score of the ‘Mood’, ‘Impulsivity’, and ‘Anger’ subscales.

^f As measured by the ‘Identity/Self-concept’ subscale.

^g As measured by the ‘Relationships’ subscale.

Figure 2. Average PTSD Symptom Scale, Self-Report (PSS-SR) scores before, during, and after treatment within each cluster.

Note: iPE = intensive prolonged exposure; Post = Posttreatment; PSS-SR = PTSD Symptom Scale, Self-Report; 3 FU = three-month follow-up; 6 FU = six-month follow-up. Average scores are based on completed assessments.

Table 2. Primary outcomes at baseline, posttreatment, three- and six-month follow-up ^a.

Outcome	Baseline	Posttreatment	Three-month follow-up	Six-month follow-up
CAPS-IV, mean (SD)	85.1 (17.2)	55.0 (30.8)	50.9 (32.9)	49.6 (30.9)
Effect size	NA	1.21	1.30 ^b	1.42 ^b
PSS-SR, mean (SD)	33.3 (6.5)	21.7 (11.6)	21.1 (12.5)	20.3 (12.7)
Effect size	NA	1.23	1.23 ^b	1.29 ^b

Note: CAPS-IV = Clinician-Administered PTSD Scale; PSS-SR = PTSD Symptom Scale, Self-Report.

^a All outcomes reflect the estimated marginal mean from the mixed model analysis. Effect sizes are Cohen’s d based on estimated data from the mixed model analysis.

^b Effect sizes are based on follow-up compared to baseline scores.

Table 3. Observed response, loss of diagnosis, and remission rates according to the CAPS-IV and PSS-SR.

Outcome	Posttreatment	Three-month follow-up	Six-month follow-up
CAPS-IV ^a
Response, n (%)	52 (71.2)	54 (74.0)	58 (79.5)
Loss of diagnosis, n (%)	22 (30.1)	29 (39.7)	33 (45.2)
Remission, n (%)	10 (13.7)	17 (23.3)	17 (23.3)
PSS-SR ^b
Response, n (%)	43 (58.9)	44 (60.3)	47 (64.4)
Loss of diagnosis, n (%)	29 (39.7)	31 (42.5)	34 (46.6)
Remission, n (%)	10 (13.7)	16 (21.9)	17 (23.3)

Note: CAPS-IV = Clinician-Administered PTSD Scale; PSS-SR = PTSD Symptom Scale, Self-Report.

^a Response defined as decrease from baseline ≥ 10 points; loss of diagnosis defined as response plus no longer meeting ‘1/2’ symptom criteria plus a severity score < 45; remission defined as loss of diagnosis plus a severity score < 20 (Schnurr & Lunney, 2016).

^b Response defined as a decrease from baseline ≥ 7 points (Doane et al., 2010); loss of diagnosis defined as a severity score ≤ 20; remission defined as a severity score ≤ 10 (Cooper et al., 2017).

Table 4. Final model with all significant predictors from the domain models.

		95% CI for Odds Ratio
Predictor	b (SE) ^a	Lower	Odds Ratio	Upper
Cluster Fast responders
Living condition	1.19 (1.27)	.27	3.29	39.69
Between-session fear habituation	.76 (.39)****	1.00	2.13	4.54
Cluster Slow responders
Living condition	−.65 (.71)	.13	.52	2.09
Between-session fear habituation	−.06 (.25)	.58	.94	1.53
Cluster Partial responders
Living condition	−1.89 (.70)***	.04	.15	.59
Between-session fear habituation	−.22 (.23)	.51	.80	1.26

Note: SE = standard error.

^a b-values represent unstandardized beta coefficients predicting the chance to belong to one of the specified clusters relative to the Non-responders cluster.

* p < .20; ** p < .10; *** p < .05; **** p = .05.

Boon, S., & Draijer, N. (1993). Multiple personality disorder in the Netherlands: A clinical investigation of 71 patients. American Journal of Psychiatry, 150, 489–494.

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Schnurr, P. P., & Lunney, C. A. (2016). Symptom benchmarks of improved quality of life in PTSD. Depression and Anxiety, 33, 247–255.

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Doane, L. S., Feeny, N. C., & Zoellner, L. A. (2010). A preliminary investigation of sudden gains in exposure therapy for PTSD. Behaviour Research and Therapy, 48, 555–560.

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Cooper, A. A., Kline, A. C., Graham, B., Bedard-Gilligan, M., Mello, P. G., Feeny, N. C., & Zoellner, L. A. (2017). Homework “dose,” type, and helpfulness as predictors of clinical outcomes in prolonged exposure for PTSD. Behavior Therapy, 48, 182–194.

 Web of Science ®Google Scholar