Which two clinical features are central to a diagnosis of major depressive disorder?

• A. Depressed mood and loss of interest or pleasure, present daily for at least two weeks.
• B. Elation and increased energy.
• C. Extreme irritability and insomnia only.
• D. Mania with grandiosity

Answer: (A)

Major depressive disorder is defined by a persistent change in mood and the ability to experience pleasure. The two features that most define it are a depressed mood and a loss of interest or pleasure (anhedonia) that occur nearly every day for at least two weeks. This combination reflects both the affective disturbance and the reduced responsiveness to rewarding experiences that characterize the disorder, and it meets the duration criterion that helps distinguish a depressive episode from transient sadness. Other options describe states not characteristic of MDD: elation and increased energy point to mania; extreme irritability with insomnia can occur in various conditions but doesn’t by itself define MDD; and mania with grandiosity is typical of bipolar disorder, not major depression.