Anxiety secondary to depression.
Studies of familial transmission, twin concordance, epidemiologic patterns, and diagnostic stability on follow-up all support the fundamental separation of affective and anxiety disorders. The importance of subdividing cosyndromal conditions by the presumed primary illness follows logically from these data, and convention suggests the use of temporal sequencing to do this; however, evidence that this approach is successful is modest. At a practical level, panic attacks seem to indicate a depression of greater severity and poorer overall prognosis. Moreover, obsessions and compulsions that develop within depressive episodes tend to differ in their themes from those that develop autonomously, and depression may precipitate only certain types of phobias. Finally, panic attacks may predict better responses to MAOIs and poorer responses to conventional tricyclic antidepressants. All of these conclusions are based on a relatively small amount of literature. Interest in this topic has grown rapidly in the past decade, and subsequent reviews will draw different, or at least additional conclusions.