Nicotine mimic improves cognition in schizophrenia

NEW YORK (Reuters Health) - A novel agent with nicotine-like properties, dubbed DMXB-A, improves the mental function of patients being treated with anti-psychotic drugs for schizophrenia, researchers report.

As the investigators point out in the Archives of General Psychiatry, people suffering from schizophrenia are often heavy smokers and this is thought be an attempt at self-medication with nicotine. Nicotinic receptors, which are involved in the brain's machinery for processing sensory input, are dysfunctional in schizophrenia.

In a proof-of-concept study, Dr. Robert Freedman, of the University of Colorado Health Sciences Center in Denver, and colleagues tested DMXB-A in12 schizophrenics on anti-psychotic medications. All patients were nonsmokers for at least one month prior to the trial, to avoid any interaction with long-term exposure to nicotine.

Two doses of DMXB-A were tested, and compared with inactive "placebo" treatment.

The investigators observed "significant neurocognitive improvement" with active treatment in scores on a test for assessing mental performance. Only the lower dose caused significant improvements in overall scores.

"Two patients spontaneously remarked that the drug helped them think more clearly and maintain concentration," the researchers report.

As a result of the positive findings, Freedman said a phase II trial has been initiated, with DMXB-A given twice a day for 2 months.

SOURCE: Archives of General Psychiatry, June 2006.