Smokers' Response to Nicotine Dependence Genotyping

Nicotine Dependence Clinical Trial

Official title: Smokers' Response to Nicotine Dependence Genotyping

Status Completed

Clinical Trial Summary

Innovative strategies to reduce adult smoking prevalence include using genetic information to motivate cessation and, ultimately, to tailor cessation pharmacotherapy. Success of these interventions depends, in part, on smokers' interest and participation in genetic testing related to cessation and their understanding and use of the results (i.e., their genetic literacy). The recent availability of genetic risk testing for a nicotinic acetylcholine receptor gene (CHRNA3) variant (rs105173) associated with nicotine dependence makes it highly feasible to investigate smokers' interest in and use of genetic information about nicotine dependence. Therefore, the primary purpose of this study is to determine the impact of an intervention that provides smokers with an educational session about genetic contributions to smoking and nicotine dependence plus their genotype results for rs1051730 on smoking cessation outcomes compared to those who receive only the educational session. Secondary purposes are to determine: (a) the impact of genetic education and knowing personal genotype results on genetic literacy outcomes and (b) the feasibility of recruitment and retention methods in a study addressing genotyping for nicotine dependence. Primary outcomes are cessation-related behaviors and cognitions indicating abstinence. Secondary outcomes are cognitions and emotions indicating genetic literacy. Knowledge gained from this study has the potential for clinical translation so that as genotyping becomes part of smoking cessation, health-care providers can understand and address factors influencing smokers' adaptation to genetically-informed cessation treatment. The study will use a longitudinal, repeated measures design (experimental, control; N=90; 45/group). All participants will receive a 90-minute educational session about genetic contributions for smoking and nicotine dependence and will donate a buccal swab sample for genotyping. The investigators will then randomize participants to two groups: those who receive genotyping results in a genetic counseling session (experimental) and those who do not (control). Follow-up data will be collected from both groups at baseline and weeks 2, 6, 10 after the experimental group receives genotyping results, with a brief follow-up and study termination occurring at week 12. Control group participants will be offered their genotyping results at the end of the study.

Clinical Trial Description

The primary aim of this study is:

Aim 1. Determine the impact of knowing personal genotyping results for nicotine dependence risk on the smoking cessation (primary) outcomes at weeks 2, 6, and 10.

The working hypotheses for the cessation-related behaviors are:

1. When compared to the control group, the experimental group will have greater: (1) smoking abstinence; (2) use of formal smoking cessation programs; (3) contact with health-care provider for cessation; (4) use of pharmacotherapy, and (5) use of self-management strategies for cessation.

2. There will be no difference in the number of quit attempts between the experimental and control groups.

The working hypotheses for the cessation-related cognitions are:

1. When compared to the control group, the experimental group will have higher self-efficacy for smoking cessation.

2. When compared to the control group, the experimental group will have higher abstainer and lower smoker self-schemas.

The secondary aims are:

Aim 2. Determine the impact of knowing personal genotyping results for nicotine dependence risk on the secondary genetic literacy (secondary) outcomes at weeks 2, 6, and 10.

The working hypotheses for the genetic literacy-related cognitions and emotions are:

1. When compared to the control group, the experimental group will have greater: (1) knowledge of genetic contributions to smoking, (2) mental representations indicating endorsement of genetic risk for nicotine dependence, (3) accurate perceptions of genetic risk for nicotine dependence, and (4) self-efficacy for use of genotyping results.

2. There will be no difference in psychological distress between the experimental and control groups.

Aim 3. Explore smokers' perceptions and experiences that contextualize participation in genetic education and genotyping for nicotine dependence risk. We will conduct focus groups with both the intervention and control group participants at weeks 2 and 6 after intervention group participants receive their genotyping results.

Aim 4. Determine the feasibility of an intervention that informs people of their personal genotype results for nicotine dependence risk for a larger clinical trial, including evaluation of enrollment (recruitment efficiency, attrition, problems and solutions), intervention fidelity (delivery, receipt, enactment), data collection, subject acceptability of the intervention, and estimation of effect sizes for sample size determination in future, larger clinical trials. ;

Related Conditions & MeSH terms

• Cigarette Smoking
• Nicotine Dependence
• Tobacco Use Disorder

• NCT number: NCT01780038
• Study type: Interventional
• Source: University of Nebraska
• Status: Completed
• Phase: N/A
• Start date: November 14, 2012
• Completion date: August 31, 2013