A claims analysis comparing citalopram with sertraline as initial pharmacotherapy for a new episode of depression: Impact on depression-related treatment charges

Abstract

Background: Citalopram, a selective serotonin reuptake inhibitor (SSRI) recently approved in the United States for treatment of depression, has similar efficacy to and a lower acquisition cost than other SSRIs. The impact of using citalopram (instead of other SSRIs) on total treatment costs has not been studied extensively. Objective: The aim of this study was to compare depression-related treatment charges for the first 6 months of treatment among patients with newly diagnosed depression who received sertraline or citalopram. Methods: This was a retrospective analysis of medical and pharmaceutical claims from 20 managed care organizations across the United States. This study population can be considered representative of a commercially insured US population. Patients aged ≥ 18 years with newly diagnosed depression (ie, major depressive disorder, dysthymia, or depressive disorder not otherwise specified) who had a prescription claim for sertraline or citalopram (within 30 days of initial diagnosis) from July 1, 1998, through June 30, 1999, were included in the study. Patients with previous mental disorders and/or treatment with an SSRI (including patients diagnosed with an anxiety disorder before the first SSRI prescription) were excluded from the analysis. Log-transformed depression-related treatment charges for the first 6 months of therapy were compared across the 2 treatment cohorts with use of multivariate regression. Other outcomes measures included medication compliance and use of other antidepressant medications during the 6-month study period. Costs were measured in year-1999 US dollars. Results: A total of 15,222 sertraline and 3175 citalopram patients met the inclusion criteria. Mean disease-related medical charges were $931 per patient in the setraline group and $1035 in the citalopram group ( P < 0.027). The difference between groups may have been due to higher mean outpatient charges in the citalopram group ($414 vs $360; P < 0.001). Citalopram patients had lower mean pharmacy charges than did sertraline patients ($255 vs $267; P < 0.036). After the data were controlled for differences in age, sex, managed care plan, pretreatment history of resource use, physician specialty type, index prescription year, and switching/augmentation of the treatment drug, depression-related charges for the citalopram patients were 22% higher than those for the sertraline cohort (beta coefficient, −0.21925; P < 0.001). Conclusion: Despite potential cost savings due to a lower acquisition cost, initial treatment of depression with citalopram was associated with higher depression-related charges than was sertraline in the population studied.