This month's issue of Psychiatric Annals, guest edited by Paul Bermanzohn, MD, reviews the various subtyping systems for patients with schizophrenia from the standpoint of their clinical utility in predicting outcome, their reliability over time, and their relationship to treatment response. From reading the articles in this series, we get a good perspective as to which subtyping systems are relevant to our current practice of treating schizophrenia.
Subtyping our patients within major diagnostic categories seems to be gaining in importance as more and better treatment tools are developed. Also increasingly, follow-up studies in depression, bipolar disorder, alcoholism, and schizophrenia are showing that specific subtypes, clinical features, or comorbid conditions may highly correlate with varying outcomes. Clinical variations of presentation within diagnostic categories are also being increasingly shown to have better outcomes with various treatments. Evidence has been published that "atypical" forms of major depression respond more often to treatment with monoamine oxidase inhibitors (MAOIs) and perhaps selective serotonin reuptake inhibitors (SSRI) than to treatment with tricyclic antidepressants (TCAs). Patients manifesting symptoms and signs of mixed or dysphoric mania have been found to respond better to anticonvulsant therapy than to what up until recently was more traditional therapy, hthium carbonate.
There is even evidence to suggest that our medications address clinical dimensions more than clinical diagnoses. This series alludes to the increased effects of atypical antipsychotic medications, compared with traditional antipsychotic medications, on negative symptoms of schizophrenia. SSRIs, introduced as antidepressant medications, are now the first-line pharmacologic treatment suggested in treatment algorithms for every differently diagnosed anxiety disorder from obsessive-compulsive disorder (OCD) to panic disorder to posttraumatic stress disorder (PTSD). Evidence is mounting from European studies that lithium carbonate may reduce the rate of suicide in patients with bipolar as well as recurrent unipolar disorders by as much as sevenfold, when dose compliance is maintained over time. Clozapine, compared with haloperidol, has been shown to reduce the suicide rate in patients who have schizophrenia, and data showing decreased frequencies of suicide attempts in patients treated with olanzapine, compared with haloperidol, raise the question of whether suicide might also be decreased in patients with affective disorders with this medication.
Biological markers seem to be correlated more with symptom dimensions than with diagnoses as well. Evidence is accumulating for this regarding psychosis, impulsiveness, aggression, vulnerability to suicide, and certain types of anxiety such as panic attacks independent of Axis I diagnoses.
If we review the evidence for effective treatment that has developed during the past 15 years, we find that we are treating specific target symptoms (this is to some extent true with some of our focused psychotherapies as well) presenting in our patients rather than diagnoses. Maybe as we learn more about the underlying pathophysiology of the disorders we treat, we will change our concepts and understanding of diagnosis, while our treatments become more effective.