**Question:** True about anorexia nervosa are all EXCEPT:

A. Anorexia nervosa is primarily a psychiatric disorder with a strong genetic component.
B. Anorexia nervosa is a rare disease affecting only elderly patients.
C. Anorexia nervosa is a gastrointestinal disorder caused by bacteria.
D. Anorexia nervosa is a life-threatening condition with high mortality rates.

**Correct Answer:** B. Anorexia nervosa is a rare disease affecting only elderly patients.

**Core Concept:** Anorexia Nervosa is a psychiatric disorder characterized by severe fear of gaining weight, leading to deliberate weight loss and malnutrition. The condition primarily affects young women, although it can also occur in men and adolescents. Its etiology is complex, involving genetic, psychological, and social factors.

**Why the Correct Answer is Right:** Anorexia nervosa is considered a psychiatric disorder because it is primarily driven by psychological factors and not simply a gastrointestinal or elderly-specific condition. The correct answer (A) highlights the genetic component and the condition's effect on young individuals.

**Why Each Wrong Option is Incorrect:**

**A.** This option highlights the importance of genetics in anorexia nervosa, which is a significant aspect of the disease. It emphasizes that anorexia nervosa affects young people, not just elderly individuals.

**B.** Anorexia nervosa is NOT a rare disease affecting only elderly patients. It primarily affects young women and adolescents, not just older individuals.

**C.** Anorexia nervosa is a psychiatric disorder, not a gastrointestinal condition. The gastrointestinal aspect of the disease is a consequence of malnutrition, not the cause.

**D.** Anorexia nervosa is not a life-threatening condition with high mortality rates. While it can lead to complications and health risks, the correct statement would be that it is a potentially life-threatening condition due to severe malnutrition.

**Clinical Pearl:** Understanding the etiology and target population of anorexia nervosa is crucial for accurate diagnosis and appropriate management. The condition affects young individuals and is driven by psychological factors, not gastrointestinal or elderly-specific causes.