Adjunctive intranasal oxytocin improves verbal memory in people with schizophrenia.
BACKGROUND
Cognitive deficits are a prominent, disabling component of schizophrenia and current pharmacological treatments have demonstrated limited efficacy in their amelioration. Oxytocin - though it has shown promise as a novel antipsychotic in multiple clinical trials - has as-yet poorly characterized effects on cognition, with some evidence indicating an amnestic profile.


METHODS
As part of a previously reported trial of chronic adjunctive oxytocin in schizophrenia, we measured its effect on two cognitive tests: the CVLT (California Verbal Learning Test) and the LNS (Letter Number Sequence). Tests were performed at baseline and after 3 weeks of treatment.


RESULTS
We found no evidence for an amnestic effect and, in fact, significantly better performance with oxytocin on several subtests of the CVLT; namely total Recall trials 1-5 (p=0.027), short delayed free recall (p=0.032) and total recall discrimination (p=0.020). In contrast we found no difference between placebo and oxytocin on LNS performance.


CONCLUSIONS
This is the first report we are aware of documenting a beneficial effect of oxytocin on cognition in schizophrenia. Though from a small sample (n=15), these data both offset past concerns about oxytocin's amnestic effects, and may auger another potential benefit in addition to the already-demonstrated salutary effects on other components of the illness.
Department of Psychiatry, University of California, San Diego, United States. dfeifel@ucsd.edu
David
D
Feifel
Kai
K
Macdonald
Patrice
P
Cobb
Arpi
A
Minassian
D000281:Administration, Intranasal; D000328:Adult; D000704:Analysis of Variance; D014150:Antipsychotic Agents / Q000008:administration & dosage*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000188:drug therapy* / Q000209:etiology*; D011939:Mental Recall / Q000187:drug effects; D008875:Middle Aged; D009483:Neuropsychological Tests; D010121:Oxytocin / Q000008:administration & dosage*; D012559:Schizophrenia / Q000150:complications* / Q000188:drug therapy; D012565:Schizophrenic Psychology; D014706:Verbal Learning / Q000187:drug effects* / Q000502:physiology
D014150:Antipsychotic Agents; D010121:Oxytocin