AIM: Our aim was to characterize utilization patterns for drugs used to treat attention deficit/hyperactivity disorder (ADHD) on the level of the individual patient among Danish users, focusing on treatment duration, doses used, and concurrent use of ADHD and non-ADHD drugs. METHODS: Using the Danish Registry of Medicinal Product Statistics, we extracted data on 1,085,099 prescriptions for ADHD drugs issued to a total of 54,024 persons in the study period 1 January 1995 to 30 September 2011. For users in the final year of the study period, we further extracted 315,365 prescriptions for non-ADHD drugs. Drug utilization was characterized using descriptive statistics. RESULTS: The mean duration of ADHD treatment was highest (3.6-4.2 years) for patients initiating therapy at a young age (age17). All age categories showed an increase in the average daily dosage of methylphenidate used from 2003 to 2010. Concomitant treatment with methylphenidate and atomoxetine was rare, as only 2 % of methylphenidate treatment overlapped with atomoxetine treatment. Nineteen percent of methylphenidate instant-release treatment overlapped with methylphenidate controlled-release treatment. Users of ADHD drugs across all age categories had an increased use of drugs related to the nervous system, especially antipsychotics [standardized morbidity rate (SMR), 6.4-19.5] and antiepileptics (SMR, 4.0-5.5). CONCLUSION: We found certain traits that warrant further investigation: the apparent increase in average daily doses, the low adherence to treatment among off-label users, and the increased use of other psychotropic medication.
European Journal of Clinical Pharmacology, 2013, Vol 69, Issue 3, p. 589-598
Adolescent Adult Age Factors Attention Deficit Disorder with Hyperactivity/diagnosis/*drug therapy/psychology Central Nervous System Stimulants/administration & dosage/adverse effects/*therapeutic use Child Child, Preschool Denmark Drug Prescriptions Drug Therapy, Combination Drug Utilization/trends Drug Utilization Review Guideline Adherence Humans Kaplan-Meier Estimate *Medication Adherence Middle Aged Off-Label Use Patient Dropouts Physician's Practice Patterns/*trends Practice Guidelines as Topic Registries Time Factors Treatment Outcome Young Adult