Attention-deficit/hyperactivity disorder in children: excess costs before and after initial diagnosis and treatment cost differences by ethnicity.

OBJECTIVES To estimate the excess costs for children in the years surrounding initial diagnosis of attention-deficit/hyperactivity disorder (ADHD) and to estimate differences in treatment costs by ethnicity. DESIGN We identified children diagnosed with ADHD and estimated their health service costs in the 2 years before and 2 years after initial diagnosis of ADHD. Costs were compared with those for children without ADHD. We adjusted for age, sex, ethnicity, pharmacy co-pay, estimated family income, coexisting mental health disorders, and chronic medical conditions. SETTING Nonprofit, integrated health care delivery system in northern California from January 1, 1996, to December 31, 2004. PARTICIPANTS Children aged 2 to 10 years with (n = 3122) and without (n = 15 899) ADHD. Main Exposure Attention-deficit/hyperactivity disorder. MAIN OUTCOME MEASURES Health care costs and use in the years before and after initial ADHD diagnosis as well as costs of ADHD-related services. RESULTS Compared with children without ADHD, children with ADHD had mean costs that were $488 more in the second year before their ADHD diagnosis, $678 more in the year before their diagnosis, $1328 more in the year after their diagnosis, and $1040 more in the second year after their diagnosis. Asian Americans diagnosed with ADHD had lower total ADHD-related mean costs per year than white Americans diagnosed with ADHD ($221 lower), and Asian Americans, African Americans, and Hispanic Americans all had lower ADHD-related pharmacy mean costs than white Americans ($95, $63, and $77 lower, respectively). CONCLUSIONS Children with ADHD use significantly more health services before and after their diagnosis than children without ADHD. Among children diagnosed with ADHD, nonwhite Americans (especially Asian Americans) use fewer ADHD-related services than white Americans.