Prescribing patterns for attention deficit hyperactivity disorder medications among children and adolescents in Korea, 2007-2011

OBJECTIVES This study analyzed the prevalence of attention deficit hyperactivity disorder (ADHD) medication use among children and adolescents in Korea between January 1, 2007 and December 31, 2011. METHODS Using the Korea National Health Insurance claims database, we identified patients between one and 17 years of age who had at least one medical claim for the diagnosis of ADHD (International Classification of Diseases, 10th revision: F90.0). The annual prevalence of ADHD diagnoses was calculated, using national census data from Statistics Korea on the population aged between one and 17 years as the denominator. The prevalence was age-standardized using the 2010 population as the standard population. The number of patients who were treated with methylphenidate and/or atomoxetine and the prevalence of total patients with ADHD that were treated with either drug were also calculated for each year. All analyses were stratified according to gender and age group (1-5 years, 6-12 years, and 13-17 years). RESULTS The number of patients diagnosed with ADHD increased from 72,704 persons (0.71%) in 2007 to 85,468 persons (0.93%) in 2011. The annual age-standardized prevalence of ADHD diagnoses increased from 0.67% in 2007 to 0.94% in 2011. The prevalence of methylphenidate use among children and adolescents with ADHD decreased from 73.91% in 2007 to 70.33% in 2011, whereas that of atomoxetine use increased from 5.77% in 2009 to 13.09% in 2011. CONCLUSIONS While methylphenidate remains the most commonly prescribed ADHD drug, the use of atomoxetine has increased.