Do oral contraceptives modulate the effects of stress induction on one-session exposure efficacy and generalization in women?

RATIONALE: The administration of glucocorticoids (GC) as an adjunct to exposure represents a promising strategy to improve one-session exposure outcome in anxiety disorders. It remains to be determined whether similar effects can be induced with the use of acute stress. Furthermore, the possible modulation of exposure effects by hormonal factors (e.g., use of oral contraceptives (OCs)) was not explored so far.

OBJECTIVES: We investigated whether acute stress prior to one-session exposure for spider fear affects its efficacy in women using oral contraceptives (OC) relative to free-cycling (FC) women. In addition, effects of stress on generalization of exposure therapy effects towards untreated stimuli were examined.

METHODS: Women with fears of spiders and cockroaches were randomly assigned to a Stress (n = 24) or No-Stress (n = 24) condition prior to one-session exposure. Of these 48 participants, 19 women used OC (n = 9 in the Stress, and n = 10 in the No-Stress group). All FC women had a regular menstrual cycle and were tested only in the follicular phase of their menstrual cycle. Pre-exposure stress induction was realized with the socially evaluated cold-pressor test. Exposure-induced changes towards treated and untreated fear stimuli were tested with behavioral approach tests for spiders and cockroaches and subjective fear and self-report measures.

RESULTS: Acute stress did not influence exposure-induced reduction in fear and avoidance of the treated stimuli (spiders). Similarly, stress had no effect on the generalization of exposure-therapy effects towards untreated stimuli (cockroaches). Exposure-induced reduction in subjective fear and self-report measures for treated stimuli was less evident in women using OC specifically after pre-exposure stress. Women using OC had higher levels of subjective fear and scored higher in self-report measures at post-treatment (24 h after exposure) and follow-up (4 weeks after exposure).

CONCLUSIONS: OC intake may represent an important confounding factor in augmentation studies using stress or GC.