The impact of comorbid premenstrual syndrome or premenstrual dysphoric disorder on the clinical characteristics of bipolar disorder among Han Chinese women

Bipolar disorder (BD) is commonly comorbid with premenstrual syndrome (PMS) or premenstrual dysphoric disorder (PMDD). However, little is known about their relationship. This study aimed to assess the impact of comorbid PMS or PMDD on the clinical characteristics of BD. A cross-sectional study was conducted on 262 women with BD. PMS and PMDD were screened with the Premenstrual Symptoms Screening Tool (PSST). Symptomatic features were assessed with Hamilton Depression Scale (HAMD), Young Mania Rating Scale (YMRS), and atypical features by the depressive episode section of SCID-I/P. The rates of PMS and PMDD among BD were 57.6% and 20.6% according to PSST. No significant difference in the rates of PMS and PMDD was found between BD I, BD II, and BD-NOS. Compared to BD patients without PMS or PMDD, patients with comorbid BD and PMS or PMDD were younger, more educated, had a higher risk of OCD, had an earlier age of onset, scored higher on HAMD-17 and its sub-scale of anxiety/somatization, cognitive deficit, psychomotor retardation, and were more likely to have increased appetite and leaden paralysis. In addition, patients with comorbid BD and PMDD were less likely to experience traumatic life events, more likely to have family history of mental disorders and have inflammatory or autoimmune disease, scored higher on HMAD-17, particularly in its sub-scale of anxiety/somatization, cognitive deficit, psychomotor retardation, and sleep disturbance. Compared with BD without PMS or PMDD, BD with PMS or PMDD might be a specific subtype of BD characterized with earlier onset age, heavier genetic load, increased symptom severity, and atypical features.