Prodromal symptoms of Chinese patients with bipolar disorder

Objective: This study aimed to assess the clinical phenomenology and characteristics of prodromal symptoms in Chinese patients with bipolar disorder (BPD) prior to their index mood episode. Methods: Semi-structured interviews [Bipolar Prodrome Symptom Scale-Retrospective (BPSS-R)] were administered to patients within 3 years of BPD (I and II) onset. Results: 120 stable inpatients and outpatients were included (65% males, mean age: 26.5±10.0 years). Feeling extremely energetic (61.8%), overly cheerful (49.1%), racing thoughts (48.2%), overly talkative (47.3%), and decreased need for sleep (43.6%) most frequently preceded the first (hypo)manic episode, whereas depressed mood (78.5%), tiredness (53.9%), reduction of enjoyment (52.3%), trouble concentrating (49.2%) and insomnia (47.7%) often occurred prior to the index depressive episode. The prevalence of anxiety or nervousness (p = 0.009), social isolation (p = 0.004), and losing temper (p < 0.001) differed significantly depending on the different episodes. Prior to any depressive episode, insomnia (p = 0.035) lasted significantly longer and sleeping too much (p = 0.033) was more severe, whereas oppositionality (p < 0.001), hallucinations (p = 0.024) and psychosis index score (p = 0.044) were more severe before any (hypo) manic episode. Furthermore, depressed mood (p = 0.006) was more frequent prior to depression, while anxiety or nervousness (p = 0.018), oppositionality (p = 0.001), and psychosis index score (p = 0.009) were more frequent before any (hypo) manic episode. Conclusions: Characteristic affective and psychotic symptoms, including depressed mood and subthreshold hypo (manic) symptoms occurred in the prodromal phase. The pre-depression prodromal symptoms lasted longer than the pre-(hypo) mania prodromal symptoms. Our findings indicated that identifying prodromal symptoms of BPD may be beneficial for early diagnosis and intervention before the development of full episodes.