Treatment outcomes after methylphenidate in adults with attention-deficit/hyperactivity disorder treated with lisdexamfetamine dimesylate or atomoxetine

PURPOSE: To compare treatment adherence, discontinuation, add-on, and daily average consumption (DACON) among adults with attention-deficit/hyperactivity disorder receiving second-line lisdexamfetamine dimesylate (LDX) or atomoxetine (ATX), following methylphenidate. PATIENTS AND METHODS: A retrospective cohort study using US commercial claims databases (Q2/2009-Q3/2013). RESULTS: At month 12, the LDX cohort (N=2,718) had a higher adherence level (proportion of days covered: 0.48 versus 0.30, P<0.001) and was less likely to discontinue (Kaplan-Meier estimate: 63% versus 85%, P<0.001) than the ATX cohort (N=674). There were no statistical differences in treatment add-on rates between cohorts (Kaplan-Meier estimate: 26% versus 25%, P=0.297). The LDX cohort had a lower DACON (1.10 versus 1.31, P<0.001) and was less likely to have a DACON >1 (adjusted odds ratio: 0.20, 95% confidence interval: 0.15-0.25, P<0.001) than the ATX cohort. CONCLUSION: Adults with attention-deficit/hyperactivity disorder treated with LDX following methylphenidate had a higher treatment adherence and lower discontinuation and DACON relative to those treated with ATX following methylphenidate.