Persistent Depressive Disorder (Dysthymia)

Persistent depressive disorder, or dysthymia, is a chronic mood disorder characterized by depressed mood for most of the day, lasting for at least two years in adults, accompanied by additional depressive symptoms such as low energy, poor concentration, and hopelessness. Etiology includes genetic vulnerability, neurotransmitter dysregulation, and environmental stressors. Clinically, patients experience chronic low mood, impaired social and occupational functioning, and diminished quality of life. Diagnosis requires longitudinal assessment, exclusion of major depressive disorder with episodic features, and identification of functional impairment. Management includes psychotherapy, pharmacologic treatment with antidepressants, and lifestyle modifications aimed at mood stabilization. Prognosis is variable, with earlier intervention improving long-term functioning and reducing risk of comorbid psychiatric conditions.