Adverse childhood experiences (ACEs) are early life experiences that may influence health outcomes across the lifespan, increasing risk for the development of psychopathology and physical/medical conditions. Data are mixed regarding the relationship between ACEs and attention-deficit/hyperactivity (ADHD), and little is known about the relationship between specific types of ACEs and development of subsequent psychopathology. This study assessed the frequency of ACEs and their association with self-reported posttraumatic stress disorder (PTSD) symptoms among adults referred for ADHD evaluation.

This cross-sectional study examined data from 307 adults referred for neuropsychological evaluation for ADHD diagnostic clarification at a large academic medical center. The sample had a mean age of 28.68 (SD=7.3); educational attainment of 16.18 years (SD=2.2); sex distribution of 42.7% male/57.3% female; and was racially/ethnically diverse. Patients completed measures of ACEs, ADHD, and psychopathology (e.g., anxiety, PTSD, depression), as well as a semi-structured interview and neuropsychological test battery. Patients were divided into groups based on ACEs exposure (No ACEs = 48, Low [<3] ACEs = 131, High (>4) ACEs = 128), per established empirical cutoffs, and based on final diagnosis (ADHD Only =104, Internalizing only = 78, ADHD+Internalizing disorder = 96, and No Diagnosis = 20). Chi-square tested level of ACEs exposure (i.e., high vs. low ACEs) across study diagnostic groups, and analysis of variance (ANOVA) assessed for differences in absolute number of ACEs experienced by diagnostic group. A linear regression elucidated the relationship between ACEs in childhood and self-reported PTSD symptoms in adulthood. Finally, for a subsample of patients with item-level data (n=161), base rates of specific ACEs were examined.

The proportion of patients endorsing high and low ACEs significantly differed between diagnostic groups (χ² (3, N=251) = 10.15, p = .017) –more patients in the Internalizing-Only group endorsed high ACEs and more patients in the ADHD-Only group reported low ACEs – and diagnostic groups significantly differed in absolute number of ACEs endorsed (F(3, 294) = 7.338, p < .001). Adverse childhood experiences significantly predicted self-reported PTSD symptoms in adulthood with ACEs accounting for 9% of the variance in PCL-5 scores (R² = .09, F(1, 265) = 28.18, p < .001). Finally, item-level analysis among a subsample of patients revealed most common ACEs endorsed included bullying (70%) and emotional abuse (63%), with at least one-third of the sample endorsing physical abuse (47%), emotional neglect (46%), parental divorce (40%), racial discrimination (38%), witnessing neighborhood violence (36%), and witnessing general community violence (35%).

Exposure to ACEs is associated with later diagnosis of ADHD and internalizing psychopathology (e.g., depression, anxiety, PTSD); however, level of ACEs endorsed may differ among those with ADHD only and those with internalizing psychopathology. Furthermore, this study provides a more comprehensive understanding of rates of endorsement of specific ACEs in a clinical sample, as well as the impact of level of ACEs exposure on the development of ADHD and internalizing psychopathology. Such findings further support the incorporation of assessment of ACEs and trauma symptoms into ADHD diagnostic evaluations to ensure accurate diagnosis and inform appropriate treatment recommendations.