• ADHD
• adults
• comorbidity
• emotional dysregulation
• functional impairment
• sex differences

Background
Attention-Deficit/Hyperactivity Disorder (ADHD) is a common neurodevelopmental disorder characterized by persistent patterns of inattention, hyperactivity, and impulsivity that significantly interfere with academic, occupational, and social functioning. While ADHD has been extensively studied in children, its persistence into adulthood has only recently received increasing attention. Epidemiological data suggest that approximately 2-5% of adults are affected worldwide, yet the clinical presentation in adults is highly heterogeneous and frequently complicated by psychiatric comorbidities. Historically, ADHD has been conceptualized primarily as a disorder of hyperactive boys, leading to diagnostic biases that contribute to underrecognition and underdiagnosis in females. These disparities can result in delayed assessment, untreated symptoms, and worse psychosocial outcomes in women. The present study aimed to explore sex-related differences in the epidemiological, clinical, and dimensional features of adult ADHD within a consecutive clinical sample, with a particular focus on symptomatology, emotional regulation, temperament, and functional impairment.
Methods
We conducted a monocentric, cross-sectional observational study at the ADHD outpatient clinic of U.O. Psichiatria 2, Azienda Ospedaliero-Universitaria Pisana. A total of 212 adult patients (95 females, 117 males; median age = 24 years, IQR 20–29were enrolled. ADHD diagnosis was established according to DSM-5-TR criteria using the DIVA 2.0 structured interview.
Participants underwent a comprehensive battery of clinician-administered and self-report measures assessing ADHD symptomatology, comorbid psychopathology, emotional dysregulation, circadian rhythm disturbances, temperament traits, impulsivity, and overall functioning. Instruments included:
• CAARS and ASRS → ADHD symptom severity
• FAST → functional impairment
• RIPoSt-40 → emotional dysregulation
• BRIAN → circadian rhythm disturbances
• HCL-32 → hypomanic symptoms
• TEMPS-M → temperament traits
• BIS-11 → impulsivity
• LPFS and PID-5-BF+M → personality dysfunction
• BRIEF-A → executive functioning.
Results
Marked sex-related differences were observed across several domains. Subtype distribution varied significantly: females more frequently exhibited the predominantly inattentive presentation, whereas males were more likely to meet criteria for the combined subtype. Males also underwent earlier assessments (median age 22 vs 26 years) and were significantly more likely to be receiving pharmacological treatment.
Conversely, females displayed higher rates of psychiatric comorbidity. Mood disorders, particularly cyclothymic presentations, were significantly more prevalent in women (56.8% vs 25.6%), along with anxiety disorders(66.3% vs 41.9%) and eating disorders (27.4% vs 5.1%).
Dimensional analyses confirmed that females reported greater ADHD severity on the ASRS and significantly higher emotional dysregulation scores across multiple RIPoSt subscales: negative emotional dysregulation, affective instability, negative emotionality and emotional instability. Females also exhibited greater circadian rhythm disruption (BRIAN), higher negative affectivity and personality dysfunction (PID-NEG, LPFS), and increased functional impairment in cognitive and leisure domains on the FAST.
Conclusions
Our findings highlight a distinct and often more severe clinical profile of adult ADHD in females. Compared to males, women presented with later recognition, internalizing comorbidities, greater emotional dysregulation, and higher functional impairment, suggesting that existing diagnostic frameworks may be insufficient for female-specific presentations. These results underscore the importance of developing sex-informed assessment protocols and personalized treatment strategies to improve detection and optimize outcomes in adult women with ADHD.