Management of patients with rapid cycling mood disorder has been a clinical challenge, including proper identification of patients (Table 1), recognition of destabilization with antidepressant use and discontinuation, and choice of appropriate medications. Typically, psychiatrists have chosen from mood stabilizers, new antiepileptic drugs, and the atypical neuroleptics.

Dr. Hussain noted a statistic of 13 to 24% of all bipolar patients having rapid cycling disease and pointed out that the most recent estimates are much higher, citing a prevalence of up to 50% of all bipolar patients. Rapid cycling is five times more common in bipolar II than bipolar I disorder, and the vast majority of rapid cycling patients (70-92%) are female.

The current study enrolled 23 patients with bipolar I (4 males, 19 females ages 17-57 years) and 37 patients with bipolar II disorder (8 males, 29 females ages 17-57 years) and followed them for three years. At outset, average duration of illness was 16.2 years for the bipolar I group and 14.7 years for the bipolar II group. All patients had received lithium carbonate, valproate, risperidone, and antidepressants in the past, and the majority were taking, or had taken, other agents as well.

At enrollment, patients discontinued use of antidepressants, lithium, and valproate; atypical neuroleptics were continued. Topiramate was initiated and continued as shown in Table 2.

Table 2

・ Initial dose 25 mg/day ・ Dose increased every 2 days as tolerated up to 200 mg/day ・ Dose further increased to maximum of 600 mg/day if needed ・ Mean dose: 1 year/ 328 mg daily - 2 years/ 339 mg daily - 3 years/ 317 mg daily

Topiramate Use in Trial

During the follow-up period of three years, 7 patients dropped out when they left the region and 13 patients discontinued topiramate. Of the patients who discontinued topiramate due to side effects, the most common problems were parasthesias (cited by 9 patients) and confusion, often with word-finding difficulty (cited by 6 patients).

Improvement in Hamilton Depression scores was evident by 3 months and continued to increase through the end of the follow-up period. At 3 years, only 3 patients were being managed with topiramate montherapy, whereas 37 patients were on polypharmacy regimens (see Table 3).

Table 3

Pharmacologic Regimens at End of Follow-up Period Monotherapy with topiramate 3 Two medications 12 Three medications 18 Four or more medications 7

The typical regimen for patients with bipolar I disorder was topiramate (often with lamotrigine) plus an atypical neuroleptic, and the typical regimen for patients with bipolar II disorder was topiramate (often with lamotrigine) plus an antidepressant agent.

Investigators concluded that topiramate-centered therapy is efficacious for patients with rapid cycling mood disorder and that such therapy is well tolerated, including weight loss for many patients. Follow-up of the patient cohort continues.

(abstract Session7 No. 21)