Rapid cycling (RC) worsens the course of bipolar disorder (BD) being associated with poor response to pharmacotherapy. Previous results about clinical variables potentially associated with RCBD were discordant or unreplicated.

An early diagnosis should be the goal to properly treat RCBD patients.

To compare clinical variables between RC and non-RC bipolar patients and to identify related risk factors.

A sample of 238 bipolar patients was enrolled from three different community mental health centers. Descriptive analyses were performed on total sample and patients were compared in terms of sociodemographic and clinical variables according to the presence of RC by multivariate analyses of variance (MANOVAs, continuous variables) or χ2 tests (qualitative variables). Binary logistic regression was performed to calculate odds ratios.

Overall, 28 patients (11.8%) had RC. The two groups were not different in terms of age, age at onset, gender distribution, type of family history, type of substance use disorder, history of antidepressant therapy, main antidepressant, psychotic symptoms, comorbid anxiety disorders, suicide attempts, thyroid diseases, diabetes, type of BD, duration of untreated illness, illness duration, duration of antidepressant treatment and GAF scores. In contrast, RC patients had more often a history of obstetric complications (P < 0.05), obesity (P < 0.05) and a trend to hypercholesterolemia (P = 0.08). In addition, RC bipolar patients presented more frequently lifetime MDMA misuse (P < 0.05) than patients without RC.

Obesity and obstetric complications are risk factors for the development of RC in BD. Lifetime MDMA misuse may be more frequent in RC bipolar patients.

The authors have not supplied their declaration of competing interest.