Differentiating premenstrual dysphoric disorder from premenstrual exacerbations of other disorders: A methods dilemma.

Premenstrual dysphoric disorder (PMDD) and premenstrual exacerbations of other disorders are difficult to distinguish. Previous methods, such as excluding women with other disorders from a PMDD diagnosis, do not enable a dual diagnosis. Our objective is to advance conceptual and clinical thinking and stimulate dialogue regarding this methods dilemma. The discussion sheds light on comorbidity in general, regardless of the disorders. Considering fundamental criteria for severe premenstrual disorders helps distinguish the phenomena of interest. A proposed method allows identification of PMDD co-occurring with other disorders. PMDD symptoms can be differentiated by their nature and timing (e.g., cyclic depressed mood could be a PMDD symptom, but cyclic binge eating or depressed mood all month long could not be). Impairment must increase premenstrually for a PMDD diagnosis. The proposed method is an advance, but specified unanswered questions remain.