A randomized comparison of psychological (cognitive behavior therapy), medical (fluoxetine) and combined treatment for women with premenstrual dysphoric disorder

This study examines the relative effectiveness of cognitive behavior therapy (CBT) (ten sessions), fluoxetine (20 mg daily) and combined therapy (CBT plus fluoxetine) in women with premenstrual dysphoric disorder (PMDD). This was a randomized pragmatic treatment trial with three treatment cells. Treatment lasted for 6 months; a naturalistic follow-up was undertaken 1 year post-treatment. One hundred and eight women, satisfying the DSM-IV criteria for PMDD with 2 months' prospective confirmation were recruited into the study; sixty of these had completed 6 months of treatment and all measures before and after treatment. The main outcome measures were premenstrual scores on the Calendar of Premenstrual Experiences (COPE) and percentage of PMDD cases (DSM-IV diagnostic criteria). Significant improvement occurred in all three treatment-groups after 6 months' treatment, assessed by the COPE. Fluoxetine was associated with a more rapid improvement. There were no group differences in the percentage of DSM cases of PMDD post treatment, but at follow-up CBT was associated with better maintenance of treatment effects compared with fluoxetine. In conclusion, CBT and fluoxetine are equally effective treatments for PMDD, but the treatments have some differential effects that can be considered in treatment decisions. There appears to be no additional benefit of combining the treatments.