A 50 year old male presents with a 3 year history of irritability, low mood, lack of interest in surroundings and general dissatisfaction with everything. There is no significant disruption in his sleep or appetite. He is likely to be suffering from-
Irritability, low mood (low self esteem, pessimism, hopelessness) and lack of interest for 3 years suggest the diagnosis of dysthymia (for details, see the table of diagnostic criteria in text).
Major depression
No psychiatric disorder
Dysthymia
Chronic fatigue syndrome