A Trend of Drug Use in Inpatients with Bipolar Disorder: A 4-Year Naturalistic Study in One Hospital

Bahk, Won Myong; Lee, Kyoung Uk; Lee, Won Hee; Park, Yuh Jin; Chae, Jeong Ho; Jun, Tae Youn; Kim, Kwang Soo; Lew, Tae Yul

Abstract

OBJECTIVE
As the limitation of lithium that is representative of the treatment in bipolar disorder is known, the use of other mood stabilizers such as carbamazepine, valproate have been increased. And with the development of pharmacotherapy, combinations of atypical antipsychotics and other drugs are a general tendency in the treatment of bipolar disorder. This study was to investigate the prescription trends in psychiatric inpatients with bipolar disorder at a university hospital and to put knowledge to practical use. METHODS: Data of 118 cases with a diagnosis of bipolar disorder according to DSM-IV from January 1998 to December 2001 were collected. Data on demographic data, duration of hospitalization, and kinds and dosages of mood stabilizers and antipsychotics were analyzed. RESULTS: In 118 subjects, 52 were male and 66 were female. In term of diagnosis, subjects with bipolar I disorder were 116 (98.3%) and subjects with bipolar II disorder were 2 (1.7%). And subjects with manic episode were 96 (81.4%), subjects with depressive episode were 17 (14.4%), subjects with hypomanic episode were 3 (2.5%) and subjects with mixed episode were 2 (1.7%). From 1998 to 2001, 95.8% of total cases were treated with the combination therapy of mood stabilizers and antipsychotics, and only 4.2% were treated with the monotherapy of a mood stabilizer. Considering mood stabilizers, the use of single mood stabilizer was 54.2% and two or more mood stabilizers combination was 45.8%. Lithium was the most commonly used mood stabilizer, and the combination of lithium and carbamazepine was the second. The mean dosage was 1060+/-207 mg/day for lithium, 665+/-131 mg/day for carbamazepine, 1056+/-258 mg/day for valproate. There was no significant change in terms of dosages used in every year. Comparing year 1998 to year 2001, the combination of mood stabilizers and antipsychotics has been increased from 90.3% to 100%. The ratio of using two or more antipsychotics decreased from 38.7% to 10.3%, but the ratio of single antipsychotics use increased from 54.8% to 89.7%. Considering the ratio of antipsychotics, typical antipsychotics decreased from 38.7% to 6.9%, but atypical antipsychotics increased from 61.3% to 93%. CONCLUSION: With the rapid and dramatic progress of psychopharmacology, the prescription trend of the pharmacotherapy in the bipolar disorder has been changed. This study suggest that the use of atypical antipsychotics has increased profoundly. We think it reflects the current progress of the treatment in the bipolar disorder.