Comorbidity case example

The anxiety disorders are a case in point. They comprise a range of conditions contiguous with the affective disorders and the stress responses (Table 4.1). Much overlap and comorbidity exist. Furthermore, definitions and diagnostic criteria have changed substantially over the years. For example, generalized anxiety disorder is a rare condition in its pure form, but a common condition if comorbid phobic and depressive disorders are accepted. 

In addition, it exerts beneficial effects in many disorders as an adjuvant to other treatment modalities. Such effects are apparent only if it is administered to an already pharmacologically treated patient. For example, in unresponsive major depressive disorder, the co-administration of lithium to an ongoing antidepressant treatment increases the response rate by up to 50%. In most cases, the response to lithium augmentation is either considerable or not at all ( all-or-none phenomenon). Some (currently not convincing) results have also been reported in unipolar depression, bulimia nervosa, and attention deficit hyperactivity disorder (ADHD). Lithium also exerts antiaggressive effects in conduct disorder, independent of any mood disorder, and can reduce behavioral dyscontrol and self-mutilation in mentally retarded patients. One of the most striking effects of lithium is its antisuicidal effect in patients who suffer from bipolar and unipolar depressive disorder irrespective of comorbid axis I disorder. ... 

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