Name two common comorbidities with Borderline Personality Disorder.

• A. Mood disorders (especially major depressive disorder) and substance use disorders.
• B. Alzheimer's disease and hearing loss.
• C. Anorexia nervosa and ADHD.
• D. Sleep apnea and hyponatremia.

Answer: (A)

Recognizing which disorders frequently co-occur with Borderline Personality Disorder helps explain the most common comorbidity pattern. Clinically, mood disorders—especially major depressive disorder—and substance use disorders are the ones seen most often alongside BPD. This overlap stems from shared features like affective instability, impulsivity, and distress intolerance, as well as common contributing experiences such as trauma and chronic dysregulation of emotion. These factors make mood symptoms and substance misuse particularly prevalent in individuals with BPD, and they significantly influence treatment needs and prognosis.

Other options describe conditions that aren’t as reliably linked to BPD. While some individuals may have co-occurring anorexia nervosa or ADHD, they are not as consistently associated as mood disorders and substance use. Medical conditions like Alzheimer's disease, hearing loss, sleep apnea, or hyponatremia are not characteristic comorbidity patterns with BPD in the same way. Remember to assess for depressive symptoms and substance use whenever a patient has BPD, as these comorbidities guide management.