Alcohol use (more than 33%) and smoking (80-90%) commonly occur together in patients with schizophrenia. Varenicline (ChantixTM) has been approved by the FDA as a medication for smoking cessation. Recent animal studies have shown that chronic varenicline administration decreased alcohol consumption. There are no human data available on the effectiveness of varenicline in alcohol-use disorders.
The aim of the proposed pilot study is to find out whether varenicline treatment decreases alcohol use and smoking in patients with schizophrenia or schizoaffective disorder. Varenicline may also improve cognition (memory and concentration) and negative symptoms (e.g. poor attention, poverty of speech, apathy, affective flattening, anhedonia) in patients with schizophrenia and comorbid nicotine and alcohol dependence.
The proposed pilot study will enroll a cohort of up to 30 subjects with schizophrenia or schizoaffective disorder and nicotine and alcohol dependence, who are receiving ongoing outpatient mental health treatment from community providers. Subjects will be randomly assigned to one of the two treatment groups (varenicline vs. placebo). Following a one week screening phase, participants will be seen on day 4, day 8, then weekly over an 8-week treatment period. One week supply of medication will be dispensed at each study visit, with the exception of the first week, when only 4 days supply will be given on 2 days (visit 1 and 2). One month after discontinuation of medication, a follow-up interview will be conducted.
Varenicline and placebo will be dispensed in 0.5 mg and 1 mg color coded capsules. During the first 3 days of treatment, participants will take one 0.5 mg tablet of varenicline (or placebo) by mouth daily. If the medication is well-tolerated, the dose will be increased to 0.5 mg by mouth twice daily for 4 days. From day 8, the dose will be increased to the standard dosing schedule of 1 mg (1 tablet) by mouth twice daily. At the end of the 8th week, varenicline will be discontinued.
A structured clinical psychiatric interview and physical exam will be performed at baseline, along with a urine drug screen, which will be repeated on week 8, and at 1 month follow-up. Blood tests (complete blood count, basic metabolic panel, liver function tests) will be performed at baseline, then monthly.
During weekly study visits patients will undergo breath carbon-monoxide and breath alcohol testing, and they will answer questions about depression, smoking and alcohol use. Detailed assessment of psychiatric symptom severity (including neuropsychological testing) will be performed at baseline, at the end of the treatment phase (week 8). A functional MRI study will be performed at baseline and at the end of study to assess changes in blood flow, emotional processing and working memory related to varenicline treatment. In addition, genetic polymorphism of the α4β2 nicotinic acetylcholine receptor and gene expression changes related to drinking/smoking/psychosis and varenicline treatment will also be assessed.
The primary objectives of the proposed study are two fold: first to determine the feasibility of conducting a similar study on a larger scale, and second to establish pilot data for determining the effect size for hypothesized treatment effects on alcohol and nicotine use based on objective tests and self report. These estimates will help inform the minimum sample size needed for a larger future trial.
