A. Kopelowicz et al., Differential efficacy of olanzapine for deficit and nondeficit negative symptoms in schizophrenia, AM J PSYCHI, 157(6), 2000, pp. 987-993
Objective: Atypical antipsychotic medications have generally been found to
be more effective than conventional antipsychotics in the treatment of nega
tive symptoms. Whether the benefits derived from the atypical agents are th
e result of improvements in primary versus secondary negative symptoms is u
nclear. The authors examined the effects of olanzapine on primary and secon
dary negative symptoms for patients with severe negative symptoms who did o
r did not have the deficit syndrome.
Method: Thirty-nine outpatients with schizophrenia and severe negative symp
toms were assessed for the presence of the deficit syndrome and entered int
o a 12-week, open-label study of olanzapine. Positive and negative symptoms
, extrapyramidal side effects, quality of life, and level of functioning of
the patients were assessed at baseline and endpoint.
Results: All 39 patients completed the 12-week protocol; 13 of the patients
had deficit negative symptoms, and 26 had nondeficit negative symptoms. Pa
tients who had nondeficit negative symptoms demonstrated improvements in po
sitive and negative symptoms, level of functioning, and extrapyramidal side
effects over baseline. In contrast, patients meeting criteria for the defi
cit syndrome improved significantly over baseline only in extrapyramidal si
de effects.
Conclusions: The results of this study suggest that olanzapine is efficacio
us for secondary negative symptoms in schizophrenia but fail to support the
contention that olanzapine has a direct beneficial effect on primary negat
ive symptoms.