Big five personality traits in adults with ADHD: Symptom associations and exploratory differences by gender and ADHD presentation

Background Adult attention-deficit/hyperactivity disorder (ADHD) is characterized by considerable clinical heterogeneity, yet the extent to which personality traits are associated with variation in symptom expression remains incompletely understood. We examined Big Five personality traits in adults with ADHD, focusing on symptom dimensions and, in exploratory analyses, ADHD presentation and gender. Methods A relatively gender-balanced clinical sample of 126 adults with ADHD completed a Likert-scale measure of the Big Five and self-report measures of ADHD symptom severity. Personality traits were compared with normative data, associations with symptom dimensions were examined, and exploratory multivariate analyses assessed differences according to ADHD presentation and gender. Results Compared with normative data, adults with ADHD showed lower Emotional Stability and Conscientiousness, but higher Openness and Agreeableness. Associations between personality traits and symptom dimensions were modest: greater inattention was associated with lower Conscientiousness, and greater impulsivity with lower Agreeableness. In exploratory analyses, personality did not differ significantly by ADHD presentation or gender alone, but a significant ADHD presentation × gender interaction was observed. Among women, those with a primarily inattentive presentation showed lower Extraversion and higher Conscientiousness than those with a combined presentation; no significant presentation-related differences were observed among men. Conclusions Personality was modestly associated with dimensional symptom variation in this clinical sample. The exploratory presentation-by-gender interaction provides preliminary evidence of presentation-related personality differences among women, but requires replication in larger, more balanced samples. Overall, the findings support a dimensional perspective on personality variation in adult ADHD without establishing diagnostic or treatment utility.