Treatment patterns among adults with ADHD receiving long-acting therapy.

OBJECTIVES: To evaluate the treatment patterns among commercially insured adults in the United States with attention-deficit/hyperactivity disorder (ADHD) who received long-acting (LA) combination therapy (CT) or monotherapy for ADHD. STUDY DESIGN: Retrospective observational study. METHODS: Adults with at least 1 ADHD diagnosis and at least 1 LA ADHD medication were identified from the MarketScan claims database (April 1, 2009, to March 31, 2014). The index date was randomly selected among LA medication initiation dates (index treatment). CT was identified if a different ADHD medication was filled within 30 days of the index date and the 2 medications overlapped by 30 days or more; otherwise, the treatment was considered monotherapy. Adherence was measured using proportion of days covered (PDC) during the 1 year post index date and was defined as a PDC of 0.8 or greater. Persistence was defined as time to discontinuation (TTD) (ie, ≥30-day supply gap). Adherence and persistence were compared between CT and monotherapy using multivariable logistic and Cox models, respectively, adjusting for baseline characteristics. RESULTS: Of 225,600 eligible patients, 7.3% received LA CT and 92.7% received LA monotherapy (mean age, 29 vs 31 years, respectively). Patients receiving LA CT had significantly lower adherence than those receiving LA monotherapy (mean PDC, 0.33 vs 0.41; adherence rate, 7% vs 16%, respectively; adjusted odds ratio, 0.38; P <.001). They also demonstrated significantly lower persistence than patients receiving LA monotherapy (median TTD, 59 vs 79 days, respectively; adjusted hazard ratio, 1.32; P <.001). CONCLUSIONS: Among US adults with ADHD treated with LA medications, LA CT was associated with significantly lower adherence and persistence compared with LA monotherapy.