Trends in incidence and characteristics of children, adolescents, and adults initiating immediate- or extended-release methylphenidate or atomoxetine in the Netherlands during 2001-2006.
BACKGROUND
Previous Dutch studies showed increasing psychostimulant use, especially methylphenidate immediate-release (MPH-IR), between 1995 and 2003. In 2003 the extended-release (ER) formulation of MPH and in 2005 atomoxetine (ATX) were introduced in The Netherlands, which increased treatment options.


OBJECTIVE
The aim of this study was to describe the change in incidence of attention-deficit/hyperactivity disorder (ADHD) drugs and the prescription profiles of patients younger than 45 years starting treatment with these medicines between 2001 and 2006.


METHODS
Data were obtained from Dutch community pharmacies as collected by the Foundation for Pharmaceutical Statistics, covering 97% of all dispenses for prescription medicines to outpatients in The Netherlands.


RESULTS
The overall incidence of ADHD drugs use increased 6.5-fold from 2001 to 2006 in men as well as in women. The absolute incidence was highest among 6- to 11-year-old boys. The percentage of first-time MPH-IR users decreased from 98.3% in 2001 to 75.9% in 2006. Likewise, MPH-ER use increased from 0% in 2001 to 18.9% in 2006, and ATX use increased from 0% in 2001 to 3.9% in 2006. The new nonstimulant drug ATX was prescribed more often to adults if they had been previously treated with selective serotonin reuptake inhibitors (SSRIs), benzodiazepines, or antipsychotics. Youngsters <17 years initiated on ATX were often previously treated with antipsychotics or clonidine/guanfacine.


CONCLUSIONS
These findings demonstrate an increase in incidence in use of ADHD drugs between 2001 and 2006 in The Netherlands. The major proportion of all treated patients comprised boys, 6-11 years old; most of them were treated with MPH-IR. In a few years time, the use of extended-release drugs as part of all ADHD drug prescriptions increased considerably, despite the lack of full reimbursement of these extended-release drugs. Psychostimulants and atomoxetine in children, adolescents, and adults are probably used to address different treatment needs.
van den Ban
Els
E
Department of Child and Adolescent Psychiatry, University Medical Centre Utrecht, Utrecht, The Netherlands.
Souverein
Patrick
P
Swaab
Hanna
H
van Engeland
Herman
H
Heerdink
Rob
R
Egberts
Toine
T
D000293:Adolescent; D018759:Adrenergic Uptake Inhibitors / Q000008:administration & dosage*; 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*; D002648:Child; D003692:Delayed-Action Preparations / Q000008:administration & dosage; D004334:Drug Administration Schedule; D011307:Drug Prescriptions / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008774:Methylphenidate / Q000008:administration & dosage*; D009426:Netherlands / Q000453:epidemiology; D011437:Propylamines / Q000008:administration & dosage*; D012737:Sex Factors; D013997:Time Factors; D016896:Treatment Outcome
D018759:Adrenergic Uptake Inhibitors; D000697:Central Nervous System Stimulants; D003692:Delayed-Action Preparations; D011437:Propylamines; D008774:Methylphenidate; D000069445:Atomoxetine Hydrochloride