Women's Health World Conference 2026

Abstract

Attention-Deficit/Hyperactivity Disorder (ADHD) has traditionally been conceptualized as a childhood condition predominantly affecting boys. However, emerging clinical evidence suggests substantial underrecognition of ADHD in women, partly attributable to less overt symptom profiles. Population-level evidence on sex differences in ADHD diagnosis and healthcare utilization remains limited in South Korea.

This exploratory study examines sex differences in ADHD diagnosis and healthcare utilization across age groups and regions using a nationally representative administrative dataset. We analyzed 17,870 observations at the district, sex, and age-group level from the 2024 Health Insurance Review and Assessment Service (HIRA) database, covering 251 districts nationwide. Outcomes included ADHD patient counts (log-transformed), per-patient medical costs, and annual visit days. Ordinary least squares regression with heteroskedasticity-robust standard errors was used, adjusting for age group, metropolitan status, and sex–age interaction terms. Robustness was assessed through province fixed effects models, adult subsample analysis (age ≥20, n=15,804), nonlinear age specifications using categorical age dummies, and regional heterogeneity analyses.

Female patients accounted for 61.1% of adult ADHD cases. After adjustment, female sex was associated with 17.9% higher ADHD patient counts compared to males (β=0.165, p<0.001), with the effect strengthening in the adult subsample (+33.6%; β=0.290, p<0.001). These findings were consistent across province fixed effects and regional subgroup models. Marginal effect analyses revealed that the female advantage increased linearly with age, from 19.6% in the youngest age group to 36.0% among those aged 90–99. Nonlinear age analysis using categorical dummies identified a peak in patient counts among those aged 60–69 (approximately +135% relative to ages 0–9), challenging the conventional view of ADHD as a childhood-onset condition.

Despite higher diagnosis counts, female patients did not incur significantly higher per-patient medical costs (β=52,097 KRW, p=0.169). In the adult subsample, female patients had significantly fewer annual healthcare visit days than males (β=−1.203 days, p<0.001), suggesting potential barriers to sustained treatment engagement following diagnosis. Metropolitan regions showed markedly higher patient counts (+73.9%) but fewer annual visit days than non-metropolitan areas.

As an exploratory analysis based on aggregate administrative data, these findings cannot establish causality, and unmeasured confounders such as clinical severity, comorbidities, and medication status warrant consideration. Nevertheless, the results consistently indicate that ADHD in women may be substantially underrecognized until mid-to-late adulthood, and that diagnosis does not translate into equivalent intensity of care. Targeted screening programs for mid-life women and strategies to improve continuity of care are needed to address unmet mental health needs and inform gender-responsive health policy.