Large studies and meta-analyses have noted that anxiety symptoms can occur in up to 65% of patients with schizophrenia, and the prevalence of any anxiety disorder (at the syndromal level) is estimated to be up to 38% [1, 2]. Anxiety symptoms are thus commonly encountered when treating patients with chronic psychotic disorders; however, of equal importance is the conclusion that more than 40% of schizophrenia spectrum patients who report an anxiety symptom are suffering from a cause other than a primary anxiety disorder or depression with anxiety. The differential diagnosis of anxiety symptoms is quite broad among patients with chronic psychotic disorders, but the correct action depends greatly on the underlying etiology. Reflexive use of a benzodiazepine or a selective serotonin reuptake inhibitor (SSRI) to treat anxiety is not appropriate in many instances and can be associated with deleterious outcomes such as increased mortality (benzodiazepines), or antidepressant-induced destabilization of patients with a bipolar diathesis (i.e. patients with a diagnosis of schizoaffective disorder, bipolar type). The issues to consider in documenting a treatment rationale are outlined in Table 8.1. A thoughtful review of the anxiety symptom evolution in relationship to medication changes or other factors should enable the clinician to arrive at a testable hypothesis and plot a course of action.
Table 8.1 Differential Diagnosis of Anxiety Symptoms in Schizophrenia Patients
||Is the anxiety related to undertreated psychotic symptoms?
||Is the anxiety due to akathisia?
||Is the anxiety related to lack of (or undertreated) mood stability in someone with a bipolar diathesis on no mood stabilizer or on an antidepressant?
||Is the anxiety associated with depressive symptoms in the absence of worsening or undertreated positive psychotic symptoms?
||Is there a primary anxiety disorder?