title: A nationwide study of attention-deficit/hyperactivity disorder drug use among adults in Iceland 2003-2012.
abstract: In this study, we leveraged on complete nationwide prescription data for the total adult population in Iceland (N = 227,000) to examine how attention-deficit/hyperactivity disorder (ADHD) drugs have been used over the past decade. In particular, we aimed to describe the prevalence, incidence and duration of use of stimulants and atomoxetine, among adults (≥19 years) in Iceland, with regard to sex, age, type of drug and specialty of the prescribing physician. Our results indicate that the 1-year period prevalence of ADHD drug use rose, from 2.9 to 12.2 per 1000 adults between 2003 and 2012, with the most pronounced increases among young adults (19-24 years). The annual incidence increased 3 times, similarly among men and women. Extended-release methylphenidate formulations were the most commonly used ADHD drugs. Specialists in psychiatry initiated treatment in 79% of new adult ADHD drug users. The proportion of users still receiving treatment after 1 year varied from 43.0% (19-24 years), 57.2% (25-49 years) to 47.5% (50+ years). After 3 years, the corresponding proportions still on treatment were 12.4%, 24.5% and 24.3%, and after 5 years 7.9%, 15.9% and 16.8%. These results of increasing ADHD drug use and short treatment durations call for further investigation of the quality of treatment regimens for adults with ADHD and better follow-up of patients treated with ADHD drugs.
authors.affiliation: Centre of Public Health Sciences, Faculty of Medicine, University of Iceland, Reykjavík, Iceland.
authors.forename: Drifa Palin
authors.initials: DP
authors.lastname: Geirs
authors.forename: Anton
authors.initials: A
authors.lastname: Pottegård
authors.forename: Matthías
authors.initials: M
authors.lastname: Halldórsson
authors.forename: Helga
authors.initials: H
authors.lastname: Zoëga
mesh_terms: D000328:Adult; D000367:Age Factors; D000069445:Atomoxetine Hydrochloride; D001289:Attention Deficit Disorder with Hyperactivity / Q000188:drug therapy*; D000697:Central Nervous System Stimulants / Q000008:administration & dosage / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007055:Iceland; D008297:Male; D008774:Methylphenidate / Q000008:administration & dosage / Q000627:therapeutic use; D008875:Middle Aged; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data* / Q000639:trends; D015995:Prevalence; D011437:Propylamines / Q000008:administration & dosage / Q000627:therapeutic use*; D013997:Time Factors; D055815:Young Adult
chemical_list: D000697:Central Nervous System Stimulants; D011437:Propylamines; D008774:Methylphenidate; D000069445:Atomoxetine Hydrochloride