Personality Disorders

Personality disorders are a group of enduring, inflexible patterns of thinking, feeling, and behaving that deviate significantly from cultural expectations, cause significant distress or impairment, and are stable across many contexts over time. The DSM-5 recognizes ten distinct personality disorders organized into three clusters: Cluster A (odd or eccentric, including paranoid, schizoid, and schizotypal), Cluster B (dramatic or erratic, including borderline, antisocial, histrionic, and narcissistic), and Cluster C (anxious or fearful, including avoidant, dependent, and obsessive-compulsive). The prevalence of any personality disorder among U.S. adults is approximately 9.1%, with borderline personality disorder accounting for 1.4%. Roughly 1 in 11 Americans aged 18 and older meet diagnostic criteria for at least one personality disorder — a rate higher than the global prevalence of 7.8%. Personality disorders are diagnosed in 40–60% of psychiatric patients, making them the most common of all psychiatric diagnoses in clinical settings, and between 65–90% of people treated for a substance use disorder have at least one co-occurring personality disorder. Despite their prevalence and serious impact on functioning and relationships, personality disorders remain among the most undertreated mental health conditions, often requiring long-term, specialized psychotherapy such as dialectical behavior therapy (DBT) or schema therapy.