Independent effects of tobacco abstinence and bupropion on cognitive function in schizophrenia.
OBJECTIVE
The objective of this study was to examine the effects of tobacco abstinence and bupropion treatment on cognitive functioning in adult smokers with schizophrenia in the setting of a randomized, double-blind, placebo-controlled clinical trial of bupropion for smoking cessation.


METHODS
Fifty-three adults with schizophrenia (DSM-IV) took part in a trial of bupropion for smoking cessation. Subjects were enrolled in the study from August 1999 to March 2003. Forty-five subjects remained in the trial at week 4; 41 subjects, 19 taking bupropion and 22 taking placebo, completed the baseline and week 4 cognitive assessments and were included in the analysis of adjusted effects of abstinence and bupropion treatment on cognitive function.


RESULTS
Controlling for bupropion treatment and baseline performance, 7 days of tobacco abstinence was associated with slowed motor speed (finger tapping) but was not associated with worsening of performance on tests of attention (AX Continuous Performance Test [AX-CPT]), verbal learning and memory (California Verbal Learning Test [CVLT]), working memory (digit span), or executive function/inhibition (Stroop) and was not associated with worsening of any clinical measures. Controlling for abstinence status, bupropion was associated with reduction (improvement) in reaction time variability on the AX-CPT and with reduction in perseverative errors on the CVLT.


CONCLUSIONS
We conclude that 1 week of tobacco abstinence is associated with slowed motor speed but is not associated with detectable worsening in performance on a range of neuropsychological tests or clinical symptoms in the subset of patients who were able to quit smoking. We also conclude that bupropion treatment may be associated with improvement in variability of attention.
Evins
A Eden
AE
Schizophrenia Program , the Tobacco Treatment and Research Center, Massachusetts General Hospital, Boston, MA 02114, USA. a_eden_evins@hms.harvard.edu
Deckersbach
Thilo
T
Cather
Corinne
C
Freudenreich
Oliver
O
Culhane
Melissa A
MA
Henderson
David C
DC
Green
Michael F
MF
Schoenfeld
David A
DA
Rigotti
Nancy A
NA
Goff
Donald C
DC
D000328:Adult; D001288:Attention / Q000187:drug effects / Q000502:physiology; D016642:Bupropion / Q000627:therapeutic use*; D003072:Cognition Disorders / Q000175:diagnosis / Q000188:drug therapy / Q000628:therapy*; D003692:Delayed-Action Preparations; D018765:Dopamine Uptake Inhibitors / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D009538:Nicotine / Q000009:adverse effects; D010919:Placebos; D011597:Psychomotor Performance / Q000187:drug effects / Q000502:physiology; D012559:Schizophrenia / Q000175:diagnosis / Q000188:drug therapy / Q000628:therapy*; D012565:Schizophrenic Psychology; D016540:Smoking Cessation / Q000379:methods*; D013375:Substance Withdrawal Syndrome / Q000517:prevention & control / Q000523:psychology; D014029:Tobacco Use Disorder / Q000517:prevention & control; D016896:Treatment Outcome
D003692:Delayed-Action Preparations; D018765:Dopamine Uptake Inhibitors; D010919:Placebos; D016642:Bupropion; D009538:Nicotine