Treatment of monozygotic twins with obsessive compulsive disorder using cognitive therapy and exposure with ritual prevention.
BACKGROUND
Assessment and treatment of cohabiting monozygotic (MZ) twins with obsessive compulsive disorder (OCD) is a possible challenge for clinical psychologists.


OBJECTIVE
This study aims to present a detailed history of two sets of cohabiting MZ twins with OCD, and describe the adaption of cognitive behavior therapy in their treatments.


METHODS
Two sets of cohabiting MZ twins completed a structured intake and the Yale Brown Obsessive Compulsive Scale as well as measures of depression, anxiety, a measure of obsessive beliefs, and thought action fusion. One set received cognitive behavior therapy and exposure with ritual prevention (ERP) simultaneously and the other received ERP separately. Pre-, post-treatment and follow-up assessments occurred for both sets of twins.


RESULTS
All four individuals showed notable decreases in OCD, and results were maintained for three of the four participants at follow-up points.


CONCLUSIONS
This study highlights the developmental course of OCD that can occur in cohabiting twins, and the clinical adaption that may be necessary.
Twohig
Michael P
MP
Utah State University, Logan, UT 84322, USA. michael.twohig@usu.edu
Whittal
Maureen L
ML
Peterson
Katherine A
KA
D000328:Adult; D015928:Cognitive Behavioral Therapy / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D009771:Obsessive-Compulsive Disorder / Q000517:prevention & control / Q000523:psychology* / Q000628:therapy*; D014430:Twins, Monozygotic / Q000523:psychology*