DEPRESSION Depression, that is major depressive disorder (MDD), is a calamity for individuals and society. If we have not experienced it ourselves, we all know someone who has been struck by this disease. Twenty percent of women and 15 per cent of men suffer at least one episode in their lifetime. In the USA, the lifetime prevalence in the general population is estimated at 16.2 per cent. MDD is characterized by two or more weeks of depressed mood or diminished interest, associated with symptoms such as disturbed sleep, decrease in appetite and libido, psychomotor changes, reduced concentration, excessive guilt and suicidal thoughts or attempts. It is insidious and often recurrent. Although depressive episodes can be treated well with antidepressant medication, structured forms of psychotherapy or a combination of these, the rate of recurrence is high, with each episode raising the probability of a new one by 16 per cent. MDD is the second leading cause of disability worldwide, i...