Frequency and Impact of Bipolar Disorder Types in Patients with Fibromyalgia

Background: Fibromyalgia (FM) is a rheumatic illness that is characterised by widespread chronic pain, fatigue and psychiatric disorders, including depression and bipolar disorders, which may occur concomitantly with FM. Aim of the Work: To evaluate the frequency of bipolar disorder types in FM patients and to assess the impact of their types on the functional status. Patients and Methods: This study enrolled 55 female patients with FM and 55 age and sex-matched controls. Functional status was evaluated using the Fibromyalgia Impact Questionnaire (FIQ). All participants were assessed for psychiatric disorders using the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I), the Hamilton Depression rating scale (HDRS), the Young Mania Rating Scale (YMRS) and the Hypomania Symptom Checklist (HCL-32). Results: Bipolar disorder II was diagnosed in 12.7% of FM patients but in none of the control group. According to SCID-I, irritability as a symptom of a hypomanic episode was more frequent in FM ( n = 39, 70.9%) patients versus two (3.6%) controls ( P < .0001). Dysthymic disorder symptoms were reported only in FM ( n = 21, 38.1%). Only one FM patient reported delusions and psychotic symptoms. Depression was diagnosed with 78.2% of FM patients, compared to 7.3% of controls ( P < .0001). Hypomanic symptoms were present in 72.7% of FM patients and in 3.2% controls only ( P < .0001). There was a significant correlation between the FIQ and mood disorders and hypomania ( P < .0001, P < .02). Conclusion: Bipolar disorder II is more frequent in FM patients than in healthy controls, contributing to the exacerbation of the disease symptoms and increased functional impairment.