A constellation of symptoms including sleep disturbance, loss of interest, change in appetite, and difficulty in concentrating reflects regional brain dysfunction. Recent investigations in neuroimaging have shown that certain areas of the brain are abnormal in patients with anxiety and depression. This regional dysfunction may be genetic or secondary to stroke, dementia, electrolyte disturbance, or other etiologies. The abnormality in some brain regions on imaging studies may actually predict response to antidepressant therapy. While some underlying medical conditions, such as hypothyroidism, may be specifically treated, others, such as stroke, may not.
Treatment can be either with a single drug or with combination therapy.
Depression with significant anxiety can be treated with an antidepressant alone. Newer drugs like venlafaxine, nefazodone, and paroxetine work for either anxiety or depression. Combined therapy may include both an antidepressant and an anxiolytic. While benzodiazepines may have deleterious effects on cognition in elderly patients, they have the advantage of working quickly. They may be used on an as-needed basis.