Indication and use of drug products used to treat attention-deficit/hyperactivity disorder: A cross-sectional study with inference on the likelihood of treatment in adulthood

Introduction: Published literature suggests that attention-deficit/hyperactivity disorder (ADHD) affects 4% of adults and that as many as 60% of children with a diagnosis of ADHD will continue to have problems with inattention and impulsivity in adulthood. We analyzed cross-sectional prescription claims data and data from a national survey of office-based physicians for further inference on the likelihood of treatment with ADHD medications into adulthood. Methods: This study used data from a proprietary, national survey of office- based physicians (the IMS Health National Disease and Therapeutic Index, NDTI (TM)) to describe the indication associated with office visits with mention of common stimulant medications and atomoxetine. Enrollment and prescription claims data maintained by a large national health-care company were analyzed for age-specific utilization of these same agents. Results: Data from the NDTI (TM) suggest that the vast majority of visits associated with a stimulant medication or atomoxetine was coded with a diagnosis consistent with a mental health condition and not obesity/weight loss. The health plans included in this study processed 222,096 prescriptions for stimulant medications and atomoxetine among 43,175 unique patients aged 1-64 years during the calendar year 2004. Analyses of pharmacy claims data showed a steep increase in use through age 11 (prevalence = 70.3 per 1,000 covered lives) followed by a marked decrease and plateau from age 25 through age 64 years (prevalence = 5 to 10 per 1,000 covered lives). Conclusions: On the basis of comparison of the prevalence rate peak of 70 per 1,000 around age 11 years to a plateau of 7 per 1,000 during the early career years, our results are consistent with a prediction that at least one child in 10 placed on an ADHD medication in childhood will receive treatment into adulthood. The decrease in the prevalence of use of these medications with advancing age as seen in this cross-sectional study may reflect upon several clinical and secular factors.