Attention-Deficit/Hyperactivity Disorder (ADHD) and Borderline Personality Disorder (BPD): Examining the overlapping features, co-occurrence, and sex differences

Research connecting Attention Deficit/Hyperactivity Disorder (ADHD) and Borderline Personality Disorder (BPD) is growing. The disorders share several overlapping characteristics, neurological deficits, and similar comorbid disorders. Although these disorders are typically sex-specific, the presence of externalizing and internalizing characteristics may link these disorders. These commonalities have resulted in a developing theory suggesting that a childhood ADHD diagnosis may predict adult BPD symptoms. The current study aimed to test this developing theory. The sample included 175 emerging adults (64.6% female). A demographics measure, the Barkley Adult-ADHD Rating Scale— IV (BAARS-IV), and the Personality Assessment Inventory Borderline Personality Features Subscale (PAI-BOR) were administered in an online format. The results suggested that ADHD and BPD were significantly correlated. The theory that childhood ADHD predicted BPD symptoms was not supported. Further, results suggested that sex differences did not play a significant role in the relationship between ADHD and BPD. Implications, such as consideration of combined treatment approaches, are discussed.