Medication use in adults with attention deficit/hyperactivity disorder in a commercially-insured population in the United States

OBJECTIVE:

To examine real-world prescription medication usage among commercially-insured adults with attention deficit/hyperactivitydisorder (ADHD) in the US.

METHODS:

Adults with ADHD who received ≥1 ADHD medication during 2013 were identified from a large US claims database. Combination therapy was defined as an overlap of ≥30 days between the index (first treatment ≥30 days in 2013) and another medication(s). Patients were classified into six groups: long-acting (LA) monotherapy, short-acting (SA) monotherapy, LA + LA, SA + SA, LA + SA, and >2 therapies. Analyses compared baseline characteristics by regimen, ranked combination regimens, and estimated daily average consumption (DACON) for monotherapy users.

RESULTS:

Of 206,443 adults with ADHD (mean age = 32.9 years; 51.6% female), 56.9% used LA monotherapy, 30.7% SA monotherapy, and 12.5% used combination therapies (LA + SA: 10.3%; LA + LA: 1.3%; SA + SA: 0.4%; >2 therapies: 0.5%). Extended-release mixed amphetamine salts (MAS-XR, 39.2%) and lisdexamfetamine (LDX, 31.5%) were the most common LA monotherapies. Nearly all SA monotherapy patients received immediate-release mixed amphetamine salts (MAS-IR; 81.7%). The top three therapies among combination categories were: (a) LA + LA: branded MAS-XR + generic MAS-XR (13.7%), LDX + generic MAS-XR (10.8%), LDX + guanfacine ER (10.7%); (b) SA + SA: generic MAS-IR + clonidine IR (33.5%), generic MAS-IR + generic MPH SA (17.9%), branded MAS-IR + generic MAS-IR (11.1%); (c) LA + SA: generic MAS-XR+/-IR (39.2%), LDX + generic MAS-IR (16.7%), LA + SA generic MPH (12.6%). Among monotherapy users, DACON was 1.2 ± 0.6 (LA) and 2.1 ± 0.9 (SA) tablets.

CONCLUSIONS:

There is significant treatment heterogeneity among US adults with ADHD. A sizable proportion of patients received monotherapies at above the recommended dosages or combination therapies, suggesting existing single-tablet regimens may not meet patients' needs.