Variance in Mood Symptoms Across Menstrual Cycles: Implications for Premenstrual Dysphoric Disorder.

Premenstrual dysphoric disorder (PMDD) remains a controversial diagnosis: Some authors have argued that it pathologizes normal mood changes, and others have questioned the need for daily mood reports across multiple cycles. In the present study, we examined changes in mood among psychologically healthy young participants with regular menstrual cycles. We collected daily reports of negative mood (depression, nervousness, irritability, and fatigue) across two to six consecutive cycles from 27 participants aged 18-35 years, and we used variance decomposition analyses to examine how much of the variance in these daily reports was due to day, cycle, and individual. The majority of variance (79%-98%) was due to daily fluctuations and did not conform to a standard pattern of premenstrual rise/postmenstrual fall. These findings suggest that PMDD is not simply an exaggeration of mood patterns typical for psychologically healthy people. Individual patterns were relatively stable from cycle to cycle; thus tracking deviations from a patient's own normative mood patterns may have greater clinical utility than deviation from a presumptive norm.