Neural Inhibition as a Mechanism of Nicotine Dependence Among Persons With Schizophrenia

What Was Tested

The trial (not phased) is built around Therapeutic nicotine (patch, non-peptide).

It had three arms (groups): 1A (experimental), 1B (placebo comparator) and 2A (experimental).

The registry classes the interventions as behavioral, drug and other.

More on the Plan

The prevalence of smoking is unusually high among patients with SCZ.

However, the mechanism(s) underlying this effect are unknown.

However, these studies have been hampered by several methodological and conceptual shortcomings including small sample sizes, the presence of confounding variables (e.g., the effects of nicotine withdrawal), and limited testing of relevant symptom domains.

Furthermore, previous studies have examined only isolated aspects of the proposed model, leaving many of the central relationships between variables untested and speculative.

Who Took Part

Enrollment: 120 planned participants were the target.

It was open to people of any sex aged from 18 years up to 60 years.

Healthy volunteers could join, not only people with the condition.

Examples of who could join: Voluntary and competent to consent. Have a diagnosis of schizophrenia, schizophreniform, or schizoaffective disorder as confirmed by the Structured Clinical Interview for the DSM-IV (SCID-IV). Between the ages of 18 and 60.

The full record lists 3 inclusion and 6 exclusion criteria; among the exclusions: have a dsm-iv history of substance abuse or dependence (other than caffeine or nicotine) in the last 6 months; have a self-reported concomitant major medical or neurologic illness; currently prescribed medications known to deleteriously affect cognition (e.g., benzodiazepines, tricyclic anti-depressants, anticholinergics, mao inhibitors, gaba-b agonists).

How the Study Was Run

It was run as a randomized, parallel-group and triple-blind study.

Because people in this Therapeutic nicotine (patch, non-peptide) study were split into groups at random, differences between the groups are less likely to reflect who happened to join each one.

The Therapeutic nicotine (patch, non-peptide) group and the comparison group ran side by side rather than switching.

Neither the participants nor the staff measuring them knew who was on Therapeutic nicotine (patch, non-peptide), so expectations could not easily colour the readings.

Those kept unaware of assignments: participant, care provider and investigator.

It started in 2007-02 with completion listed for 2008-08.

It ran at 1 site in Canada.

Its stated primary purpose is basic science.

What Was Measured

Primary outcome: neural inhibition via EEG and TMS (time frame: intermittent).

It also tracked 2 secondary outcomes, for example Self reported tobacco use and Polymorphic markers in the CHRNA7 gene and promoter region.

What This Means in Plain Language

Put simply, this is a not phased, randomized trial of Therapeutic nicotine (patch, non-peptide) in 120 people.

The trial is marked completed; no results are posted to the registry yet, so nothing here describes outcomes.

More context: the Therapeutic nicotine (patch, non-peptide) compound page, all human trials.