Varenicline Treatment for Smoking Cessation in Patients With Bipolar Disorder

OBJECTIVE:

Our primary objective is to determine if adjunctive varenicline will be efficacious (vs. placebo) in initiating abstinence from smoking cigarettes in subjects with stable bipolar disorder who are motivated to quit smoking during a 12-week treatment phase. A secondary outcome is to determine whether those who initiated abstinence during the 12-week treatment phase will maintain abstinence in the subsequent three-month follow-up period off study medications.

Additional outcomes: we plan to test the effectiveness of varenicline in reducing nicotine withdrawal symptoms or urges to smoke, as well as its safety for use in stable bipolar patients when used as an adjunctive treatment for smoking cessation.

RESEARCH PLAN:

We plan to test these hypotheses by conducting a randomized, placebo-controlled, treatment trial of Chantix. Measures of CO levels in expired air (10 ppm or lower), self-reported abstinence, and psychopathology ratings will be used to evaluate primary and secondary outcomes along with safety assessments. Smoking abstinence is defined as 7-day point prevalence of self-reported no smoking verified objectively by expired CO levels of 10 ppm or less, and will be assessed at 12-weeks (or end of treatment phase) as the primary outcome. The same criterion will be used to assess maintenance of abstinence in the non-treatment phase, i.e. at 24 weeks or end of study.

METHODS:

Seventy-six subjects with DSM-IV bipolar disorder will be recruited from Western Psychiatric Institute and Clinic and Dubois Regional Medical Center. Using a 1:1 Randomization, which also takes into account gender, subjects who sign an informed consent document will be randomized to receive Chantix or placebo.

It is expected that 16 of the 76 may not meet inclusion/exclusion criteria, leaving 60 consenting adults aged 18-65 years with DSM-IV bipolar disorder, which will be confirmed by the MINI (Sheehan et al.) Subjects must meet smoking inclusion criteria of smoking 10 or more cigarettes per day. Motivation to quit smoking (score of at least 7 on the Contemplation Ladder Scale) as well as stable mood status (Young Mania Rating Scale score of eight or less, Montgomery Asberg Depression Rating Scale Score of eight or less, with low scores on suicide aggression and psychotic items over a four-week period required. Subjects who have received pharmacological agents for smoking cessation such as bupropion, nicotine replacement treatment, or who have participated in behavioral treatment for smoking cessation more than three months before beginning the study will be permitted to enroll in the study. Anyone experiencing serious side-effects from varenicline in the past or who has already participated in a smoking cessation study with varenicline will be excluded.

Chantix or placebo will be administered using random assignment at a dose of 0.5 mg by mouth for three days, followed by 0.5 mg twice per day for four days. After the first week, the dose will be increased to 1 mg twice daily for 11 weeks. Subjects must be able to tolerate a minimum of 1 mg per day to continue in the study.

Subjects will pick a target date between visit 3 (to permit titration to the target dose of 2 mg per day) and visit 4 to quit smoking. There needs to be at least 24 hours (preferably 48) between the time of the last cigarette usage and visit 4, where a CO measurement will be taken.

Those who are unable to quit at this time will be given an opportunity to pick additional quit dates. All visits will be scheduled a week apart and subjects will continue to take their double-blind medication and receive counseling sessions for smoking cessation. Study medication will be stopped after 12 weeks, and there will be weekly visits to evaluate abstinence.

Some standard psychopathology rating scales and smoking rating scales will be administered to evaluate secondary aims such as the degree of nicotine withdrawal symptoms and the impact of residual symptoms on bipolar disorder. Safety will be assessed through the administration of specific mania and depression rating scales including and the Columbia -Suicide Severity Rating Scale, as well as a comprehensive health assessment. This includes a medical history and evaluation of laboratory measures. Any adverse effects of medication will be assessed by asking questions at each visit and if necessary, contacting the subject by phone outside the scheduled visits.

SIGNIFICANCE The rate of cigarette smoking among people with psychiatric disorders remains exceedingly high; nearly two to four times as high as those in the general population. Patients with bipolar disorder may have the highest rates of smoking as compared with people with other psychiatric diagnoses. To date, there have been no treatment trials of adequate size to measure smoking cessation rates in people with bipolar disorder. If varenicline proves to be an effective in helping people with bipolar disorder to stop smoking, or even to reduce their smoking rates, this could play an important role in improving their health.