Depressive disorders in old people. Here follow some statements on depressive disorders and their treatment in old people. Mark for each statement which degree of agreement you have: a. Depressive disorders in old people have more of biological causes then depressive disorders in younger ages. b. ADs are as effective in old people as in middle age people. c. Psychotherapy is as effective in old people as in middle age persons. d. ADs are effective against anxiety and behaviour disorder in people with dementia.