(250) The Pharmacotherapy Options for Attention-Deficit Hyperactivity Disorder (ADHD) in Taiwan and the Influencing Factors

Background: ADHD is a childhood-onset neurodevelopmental disorder that frequently persists into adulthood. Pharmacotherapy has consistently been used as the primary and most effective therapeutic option for managing ADHD.

Objectives: In Taiwan, there is no treatment guideline for ADHD, and the use of drugs is based on the reimbursement regulations of the National Health Insurance (NHI). Therefore, evaluating prescription patterns and considering different factors that may influence treatment is needed.

Methods: Patients under 18 years old diagnosed with ADHD between 2012 and 2018 were identified from the NHI Database. These patients were divided into two groups based on whether they received ADHD drugs or not, and baseline characteristics from one year before the diagnosis date were collected. To compare categorical and continuous variables, we employed the chi-squared test and t-test, respectively. A multivariate logistic regression model was used to estimate potential factors associated with initiation of the medication. Adjusted odds ratio (aOR) and 95% confidence intervals (CIs) were calculated.

Results: During the observation period, 144,387 patients were diagnosed with ADHD. Within this cohort, 46,634 individuals (32.3%) were identified as drug users (mean age 10, 78.8% were male). The usage of ADHD drugs was most prevalent among school-aged children (72.7%), followed by adolescents (25.2%) and preschool age children (2.1%). In terms of initial prescriptions, 83.4% of users were prescribed immediate-release methylphenidate (MPH), 12.3% long-acting MPH, and 3.4% atomoxetine (ATX). Regarding factors associated with receiving ADHD medication, comorbidities such as tic disorder, Tourette's disorder, oppositional defiant disorder, or conduct disorder decreased the probability of being prescribed IR-MPH but increased the likelihood of being prescribed LA-MPH or ATX. Regarding co-medication, individuals with a history of psychotropic drug use were more likely to be prescribed LA-MPH or ATX rather than IR-MPH.

Conclusions: In a cohort of 144,387 patients diagnosed with ADHD under the age of 18, about two-thirds were identified as users of ADHD medications, with MPH emerging as the most frequently prescribed initial drug. Notably, individuals with ADHD and concurrent comorbidities, including tic disorder, Tourette's disorder, oppositional defiant disorder, or conduct disorder, exhibited an elevated likelihood of being prescribed LA-MPH or ATX rather than IR-MPH.