The relationship between use of antidepressants and resource utilization among patients with manic or mixed bipolar disorder episodes: Findings from a managed care setting

ObjectiveTreatment guidelines for bipolar disorder (BD) recommend the tapering of antidepressants (ADs) for patients with a recent acute manic or mixed episode. This study assessed rates of AD use and the association between such use and BD-related re-hospitalizations among patients with BD.MethodsUsing the IMS LifeLink® Health Plan Claims Database from 1/1/2004 to 6/30/2007, we identified adults 18 + years of age with an acute psychiatric event (“index event”), defined as a hospitalization, emergency room visit, or physician visit, with a prescription for a new BD medication with a primary diagnosis of BD I mania (ICD-9-CM: 296.0x, 296.4x) or BD I mixed (ICD-9-CM: 296.6x). All patients were required to be eligible for the 12 months before index and during the 12-month post-index period, and have a BD-related hospitalization (any diagnosis of any BD subgroup) in the pre-index period. Patients with schizophrenia at any time during the study period were excluded. Study measures included: rates of AD use (minimum of 30 days of available AD therapy within 120 days after the index event) and the association of such use with post-index BD-related hospitalizations.Results2126 patients met study criteria (mean age 44 years; 57% female; 53% BD I mania). 32% of all patients had AD use in the post-index period. Compared to BD I patients without AD use in the post-index period, those with AD use had 1.43 to 1.50 times the odds of being re-hospitalized for BD in the follow-up period. Other significant positive predictors included being female and presence of substance abuse.LimitationsAdministrative claims data do not provide information on symptoms, which may influence continuation of antidepressants.ConclusionsIn this administrative claims database, nearly one-third of patients with BD I manic or mixed subgroups had AD use following an acute event. The positive association observed between AD use and re-hospitalization needs to be confirmed in clinical studies.