Table 1.
Characteristics and results of clinical trials of DCS-augmented CBT for anxiety disorders
| Study | Diagnosis | N | DCS Dose (mg) | Dosing timing (hrs before exposure) | # of DCS doses | CBT type (# of exposure sessions) | Primary measures | Main results (DCS vs. placebo) |
|---|---|---|---|---|---|---|---|---|
| Ressler et al., 2004 [53] |
Acrophobia |
27 |
50 or 500 |
2-4 |
2 |
VRE (2) |
SUDS, skin conductance, clinical self-reports |
Greater subjective improvement (p < .001); greater decrease in skin conductance fluctuations (p < .05); greater clinical improvement (p < .02) effects were maintained at 3-month follow-up |
| Guastella et al., 2007 [54] |
Sub-threshold spider phobia |
63 |
50 |
2-3 |
1 |
Exposure (1) |
SUDS, heart rate |
No DCS effects |
| Tart et al., 2013 [55] |
Acrophobia |
29 |
50 |
−0.5a |
2 |
VRE (2) |
SUDS, CGI-I |
No overall DCS effects. |
| Smits et al., 2013 [56] |
DCS effect on CGI-I significantly moderated by fear level at end of exposure session (b = −.05, p < .01); low levels of fear predicted greater symptom improvement |
|||||||
| Nave et al., 2012 [57] |
Snake phobia |
20 |
50 |
1 |
1 |
Exposure (1) |
Snake Questionnaire |
No overall DCS effects. |
| DCS group reached top of fear hierarchy more quickly (p < .05) | ||||||||
| Hofmann et al., 2006 [58] |
SAD |
27 |
50 |
1 |
5 |
Individual/group CBT, emphasis on exposure (5) |
SPAI, LSAS |
Greater symptom improvement (p’s < .02); effects maintained at 1-month follow-up |
| Guastella et al., 2008 [59] |
SAD |
56 |
50 |
1 |
4 |
Group CBT, emphasis on exposure (4) |
SPAI, LSAS |
Greater symptom improvement over time (p = .002). |
| Rodebaugh et al., in press [60] |
SAD |
34 |
250 |
0 |
1 |
Exposure (2) |
SUDS |
Greater reduction in subjective distress between two exposure sessions (d = 1.06) |
| Hofmann et al., in press [61] |
SAD |
169 |
50 |
1 |
5 |
CBT (5) |
LSAS, SPDS |
Faster symptom improvement, global illness severity and remission status (p’s < .05) |
| Wilhelm et al., 2008 [62] |
OCD |
23 |
100 |
1 |
10 |
Exposure-based behavior therapy (10) |
YBOCS |
No overall DCS group effect; significant time by group interaction (p = .02), with greater symptom improvement in DCS group at mid-treatment. |
| Chasson et al. 2010 [63] |
Re-analysis showed DCS increased speed of symptom improvement sixfold during the first half of treatment. |
|||||||
| Kushner et al., 2007 [64] |
OCD |
25 |
125 |
2 |
10 |
ERP (10) |
YBOCS |
Lower drop-out rate (p < .05); symptoms improved more quickly during first 4 sessions (p = .02, d = .77) |
| Storch et al., 2007 [65] |
OCD |
24 |
250 |
4 |
12 |
ERP (12) |
YBOCS |
No DCS effects. |
| Storch et al., 2010 [66] |
Pediatric OCD (ages 8–17) |
30 |
25 or 50 |
1 |
7 |
ERP (7) |
CYBOCS, CGI-S, ADIS-CSR |
Small-to-moderate DCS effects (d = .31-.47) |
| Otto et al., 2010 [67] |
PD, PDA |
31 |
50 |
1 |
3 |
Brief CBT (3) |
PDSS, CGI-S |
Greater symptom and severity reduction (p = .01, d = 1.11), maintained at follow-up (p < .05) |
| Siegmund et al., 2011 [68] |
PDA |
39 |
50 |
1 |
3 |
CBT (3) |
PAS, CGI |
No overall DCS effects; statistical trend (p = 0.075) in severely ill patients that DCS accelerated symptom reduction |
| de Kleine et al., 2012 [69] |
PTSD |
67 |
50 |
1 |
7-9 |
Prolonged Exposure (7–9) |
CAPS |
No overall DCS effects; DCS group more likely to show response (odds ratio 2.83, 95 % confidence interval [CI] 1.05–7.61). |
| Litz et al., 2012 [70] | PTSD | 26 | 50 | 0.5 | 4 | Brief CBT (4) | CAPS, PTSD Checklist | DCS associated with poorer outcome on all measures |
ADIS-CSR = Anxiety Disorders Interview Schedule-Clinical Severity Rating; CAPS = Clinician-Administered PTSD Scale; CBT = cognitive-behavioral therapy; CGI = Clinical Global Impression; CGI-I = Clinical Global Impression-Improvement; CGI-S = Clinicians’ Global Impressions of Severity; CYBOCS = Child Yale Brown Obsessive Compulsive Scale; ERP = exposure/ritual prevention or exposure and response prevention; LSAS = Liebowitz social anxiety scale; OCD = obsessive compulsive disorder; PAS = Panic and Agoraphobia Scale; PD = Panic disorder; PDA = Panic disorder with agoraphobia; PDSS = Panic Disorder Severity Scale; PTSD = posttraumatic stress disorder; SAD = social anxiety disorder; SPDS = social phobic disorder severity scale; SPQ = spider phobia questionnaire; SPAI = social phobia and anxiety inventory; SUDS = subjective units of discomfort; VRE = Virtual Reality Exposure; YBOCS = Yale Brown Obsessive Compulsive Scale.
aA DCS dosing timing of −0.5 hours indicates that DCS was administered 0.5 hours after the beginning of exposure.