Effects of Stress on Exposure Therapy

Study Overview
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Brief Summary
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This study investigates whether stress can augment exposure therapy outcome in patients with specific phobia (spider phobia).

Detailed Description
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Stress has been shown to modulate fear extinction. The present study is aimed at investigating whether stress (administered prior to exposure with the socially evaluated cold pressor test) augments exposure therapy outcome in patients with specific phobia (spider phobia). Furthermore, the effects of stress on the generalization of exposure-induced symptom reduction towards untreated fear stimuli (i.e. cockroaches) will be explored. Participants are randomly assigned to the cold or warm water condition of the socially evaluated cold pressor test (SECPT; Schwabe et al., 2008). Thereafter, participants of both conditions receive 45 minutes of in-vivo exposure to spiders. The effects of stress on exposure-based anxiety reductions toward spiders (treated fear stimulus) and cockroaches (untreated fear stimulus to assess generalization of treatment outcome) are assessed on the behavioral, subjective and physiological level at pretreatment, posttreatment (24 hours after exposure) and follow-up (4 weeks after exposure).

Official Title
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The Impact of Stress on Exposure-based Treatment Outcome

Conditions
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Specific Phobia

Intervention / Treatment
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* Other: Cold water condition
* Other: Warm water condition


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Women using oral contraceptives (OC) Specific phobia (spider phobia) Exclusion Criteria: Body Mass Index (BMI) < 19 or > 27 Pregnancy Any acute or chronic mental, somatic, endocrine, or metabolic disease Psychological, psychiatric, neurological or pharmacological treatment Shift work Smoking more than 5 cigarettes per month Vaccination in the past 2 month Drug or alcohol abuse

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Stress + Exposure<br>Stress Condition: Cold water condition of the socially evaluated cold pressor test (SECPT; Schwabe et al, 2008). | Other: Cold water condition<br>* Cold water condition of the SECPT. Participants immerse their hand into ice-cold water (0-3°C). During the SECPT, participants are videotyped and monitored. After the SECPT, participants will receive 45 minutes of in-vivo exposure to spiders<br>|
| Active Comparator: Control + Exposure<br>Control condition: Warm water condition of the SECPT. | Other: Warm water condition<br>* Warm water condition of the SECPT. Participants immerse their hand into warm water (36-37°C). Participants are neither videotyped nor monitored during the whole procedure. After the SECPT, participants will receive 45 minutes of in-vivo exposure to spiders.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in the Behavioral Approach Test (BAT) with spiders (treated fear stimulus) | During the Behavioral Approach Test (BAT) the closest distance to a spider as well as subjective fear and heart rate is measured. | Pretreatment, Posttreatment, Follow-up (with approx. 1 day between pre- and posttreatment and 4 weeks between pretreatment and follow-up) | 
| Change in the Behavioral Approach Test with Cockroaches (untreated fear stimulus) | During the Behavioral Approach Test (BAT) the closest distance to a cockroach as well as subjective fear and heart rate is measured. | Pretreatment, Follow-up (with approx. 4 weeks between pretreatment and follow-up) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in the Spider-fear Related questionnaires | Self-report questionnaires assessing fear of spiders will be used. The Fear of Spiders Questionnaire (FSQ) and the Spider Beliefs Questionnaire (SBQ) will be employed. Scores on these scales range from 0 to 108 and 0 to 100, respectively, with higher scores indicating greater fear of spiders. | Pretreatment, Posttreatment, Follow-up (with approx. 1 day between pre- and posttreatment and 4 weeks between pretreatment and follow-up) | 
| Change in the Cockroach-fear related questionnaires | Self-report questionnaires assessing fear of cockroaches will be used. The Fear of Cockroach Questionnaire and the Cockroach Beliefs Questionnaire will be employed. Scores on these scales range from 0 to 108 and 0 to 100, respectively, with higher scores indicating greater fear of cockroaches. | Pretreatment, Posttreatment, Follow-up (with approx. 1 day between pre- and posttreatment and 4 weeks between pretreatment and follow-up) | 
| Free cortisol concentrations | Manipulation check (SECPT). Saliva will be collected using salivette sampling devices (Sarstedt, Nümbrecht) at different time points to assess free cortisol concentrations and activity of the enzyme alpha amylase | 5 times at Pretreatment, 2 times at Posttreatment, 2 times at Follow-up. (with approx. 1 day between pre- and posttreatment and 4 weeks between pretreatment and follow-up) | 
| Blood pressure | Manipulation check (SECPT). Systolic and diastolic blood pressure (mm/Hg) are measured at different time points | 9 times at Pretreatment | 
| Activity of the enzyme alpha amylase | Alpha amylase will be collected using salivette sampling devices | 5 times at Pretreatment, 2 times at Posttreatment, 2 times at Follow-up ( (with approx. 1 day between pre- and posttreatment and 4 weeks between pretreatment and follow-up) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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anxiety disorders, spider phobia, stress, exposure therapy, generalization