Comparing Antidepressant Treatment Patterns in Older and Younger Adults: A Claims Database Analysis

OBJECTIVES: To compare depressed older (>= 65) and younger (25-64) adults with regard to antidepressant treatment patterns and to assess factors associated with 180-day nonpersistence. DESIGN: Retrospective matched cohort study. SETTING: U.S. managed care population. PARTICIPANTS: Older and matched younger adults diagnosed with depression and treated with antidepressants. MEASUREMENTS: Sociodemographic characteristics, comorbidities, polypharmacy, and characteristics of antidepressant treatment at 180 days were compared between older and younger adults. Analyses were conducted before and after the implementation of Medicare Part D on January 1, 2006, to consider the effect of this policy. RESULTS: Few participants received psychotherapy, especially older ones; rates were constant before and after 2006. Before 2006, older adults more frequently received antidepressants at lower (odds ratio (OR) -5.38, 95% confidence interval (CI) = 3.57-8.13) or intermediate dose (OR = 2.42, 95% CI = 1.93-3.02) and had poorer adherence to treatment (P<.001) than younger adults. After 2006, older adults received similar proportions of intermediate or high antidepressant doses as younger adults, but a lower dosage was still more likely to be prescribed (OR = 1.87, 95% CI = 1.09-3.20) and had higher treatment adherence (P<.001). Medication profile did not significantly affect the risk of nonpersistence, but increased with lower antidepressant dose (P<.001). Whereas nonpersistence was higher in older adults before 2006 (hazard ratio (HR) = 1.25, 95% CI = 1.22-1.46), the trend reversed after 2006 (HR = 0.76, 95% CI = 0.66-0.88). CONCLUSION: More than half of participants with depression discontinued antidepressant treatment, and psychotherapy was rarely used. Implementation of Medicare Part D was associated with substantial changes in treatment of older adults with depression. The presence of comorbidities or polypharmacy was not associated with nonpersistence in depressed older adults. J Am Geriatr Soc 59:1197-1205, 2011.