Adjuvant aspirin therapy reduces symptoms of schizophrenia spectrum disorders: results from a randomized, double-blind, placebo-controlled trial.
OBJECTIVE
Inflammatory processes may play a role in the pathophysiology of schizophrenia. The aim of this study was to determine the efficacy of adjuvant treatment with aspirin (acetylsalicylic acid) in schizophrenia spectrum disorders.


METHODS
This randomized, double-blind, placebo-controlled study was conducted between May 2004 and August 2007. Seventy antipsychotic-treated inpatients and outpatients from 10 psychiatric hospitals in The Netherlands with a DSM-IV-diagnosed schizophrenia spectrum disorder were included. Patients were randomized to adjuvant treatment with aspirin 1000 mg/d or placebo. During a 3-month follow-up, psychopathology was assessed with the Positive and Negative Syndrome Scale (PANSS). Other assessments included cognitive tests and immune function. The primary efficacy outcome was the change in total PANSS score. Secondary outcomes were changes in the PANSS subscales and cognitive test results.


RESULTS
Mixed-effect models showed a 4.86-point (95% CI, 0.91 to 8.80) and 1.57-point (95% CI, 0.06 to 3.07) larger decrease in the aspirin group compared to the placebo group on the total and positive PANSS score, respectively. Similar but not statistically significant results were observed for the other PANSS subscale scores. Treatment efficacy on total PANSS score was substantially larger in patients with the more altered immune function (P = .018). Aspirin did not significantly affect cognitive function. No substantial side effects were recorded.


CONCLUSIONS
Aspirin given as adjuvant therapy to regular antipsychotic treatment reduces the symptoms of schizophrenia spectrum disorders. The reduction is more pronounced in those with the more altered immune function. Inflammation may constitute a potential new target for antipsychotic drug development.


BACKGROUND
controlled-trials.com Identifier: ISRCTN27745631.
Laan
Wijnand
W
Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, PO Box 85500, 3508 GA, Utrecht, The Netherlands. W.Laan@umcutrecht.nl
Grobbee
Diederick E
DE
Selten
Jean-Paul
JP
Heijnen
Cobi J
CJ
Kahn
René S
RS
Burger
Huibert
H
D000328:Adult; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000627:therapeutic use*; D014150:Antipsychotic Agents / Q000627:therapeutic use; D001241:Aspirin / Q000008:administration & dosage / Q000627:therapeutic use*; D017024:Chemotherapy, Adjuvant; D016001:Confidence Intervals; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000097:blood; D015847:Interleukin-4 / Q000097:blood; D008297:Male; D011569:Psychiatric Status Rating Scales; D011581:Psychological Tests; D012559:Schizophrenia / Q000188:drug therapy*; D018417:Th1 Cells / Q000187:drug effects; D018418:Th2 Cells / Q000187:drug effects; D016896:Treatment Outcome
D000894:Anti-Inflammatory Agents, Non-Steroidal; D014150:Antipsychotic Agents; D015847:Interleukin-4; D007371:Interferon-gamma; D001241:Aspirin