0
Get Alert
Please Wait... Processing your request... Please Wait.
You must sign in to sign-up for alerts.

Please confirm that your email address is correct, so you can successfully receive this alert.

1
Brief Reports   |    
Negative symptoms: a path analytic approach to a double-blind, placebo- and haloperidol-controlled clinical trial with olanzapine
Am J Psychiatry 1997;154:466-474.
text A A A
PDF of the full text article.

Abstract

OBJECTIVE: The authors investigated whether primary negative symptoms of schizophrenia are enduring or treatment-responsive. METHODS: Previously, a double-blind, random-assignment trial of the novel antipsychotic olanzapine (in low, medium, and high dose ranges), placebo, or haloperidol (10-20 mg/day) for 335 schizophrenic inpatients was conducted for up to 52 weeks. Changes in the treatment groups from baseline to endpoint in summary scores on the Scale for the Assessment of Negative Symptoms (SANS) and several secondary measures were compared. This article describes a path analysis to determine to what extent the total treatment effect on negative symptoms was direct or indirect (i.e., mediated by differential effects on positive symptoms, extrapyramidal symptoms, or mood). RESULTS: Significantly greater improvement was achieved with high-dose olanzapine than with placebo or haloperidol. Olanzapine had a significantly greater direct effect than placebo on all SANS dimensions except anhedonia-asociality. Olanzapine also demonstrated a significantly greater direct effect than haloperidol on negative symptoms, especially on the dimensions of affective flattening and avolition-apathy. Olanzapine's superior effects were replicated in a subgroup with SANS-defined prominent negative symptoms (N = 116) and a subgroup with a BPRS-defined cross- sectional proxy for the deficit state (N = 117). CONCLUSIONS: These results suggest that the negative symptoms of schizophrenia are directly responsive to treatment. The significantly greater direct and indirect effects of olanzapine than of haloperidol on negative symptoms are likely related to olanzapine's pleotrophic pharmacology, which includes dopaminergic, serotonergic, muscarinic, and adrenergic activities. The results contribute to the hypothesis that negative symptoms may be under the influence of several neurotransmitters within one or more neuroanatomic circuits.

Abstract Teaser
Figures in this Article

+

References

+
+

CME Activity

There is currently no quiz available for this resource. Please click here to go to the CME page to find another.
Submit a Comments
Please read the other comments before you post yours. Contributors must reveal any conflict of interest.
Comments are moderated and will appear on the site at the discertion of APA editorial staff.

* = Required Field
(if multiple authors, separate names by comma)
Example: John Doe



Web of Science® Times Cited: 246

Related Content
Articles
Books
The American Psychiatric Publishing Textbook of Psychopharmacology, 4th Edition > Chapter 29.  >
The American Psychiatric Publishing Textbook of Psychopharmacology, 4th Edition > Chapter 61.  >
APA Practice Guidelines > Chapter 7.  >
APA Practice Guidelines > Chapter 7.  >
The American Psychiatric Publishing Textbook of Psychopharmacology, 4th Edition > Chapter 61.  >
Topic Collections
Psychiatric News
Read more at Psychiatric News >>
APA Guidelines
PubMed Articles