Results : We confirmed the importance of the 4 main factors influencing SC : ( 1 ) environmental factors , ( 2 ) genomic factors , ( 3 ) gene-environment interactions , and ( 4 ) evidence -based interventions .
The model demonstrates the complex network of factors influencing SC .
Background : Smoking behaviour is a major public health problem worldwide .
Several sources have confirmed the implication of genomic factors in smoking behaviour .
These factors interact both with environmental factors and interventions to develop a certain behaviour .
Objectives : Describing the environmental and genomic factors as well as the interventions influencing smoking cessation  ( SC ) and developing a working model incorporating the different factors influencing SC were our main objectives .
CYP2B6 Genotype Alters Abstinence Rates in a Bupropion Smoking Cessation Trial
BACKGROUND CYP2B6 is the primary enzyme involved in bupropion ( Zyban ; GlaxoSmithKline , Research Triangle Park , North Carolina ) metabolism . Genetic polymorphisms in CYP2B6 , such as CYP2B6 * 6 , can alter bupropion metabolism and may affect bupropion treatment outcome . METHODS Subjects participated in a smoking cessation clinical trial of bupropion versus placebo . The main outcome was a 7-day point prevalence abstinence rate measured 10 weeks after the start of treatment ( i.e. , end of treatment ) and at the 6-month follow-up ; secondary outcomes were severity of adverse effects , withdrawal , and urge to smoke . Subjects were haplotyped for the CYP2B6 * 6 variants . RESULTS Among smokers in the CYP2B6 * 6 group ( CYP2B6 * 1/*6 or CYP2B6 * 6/*6 genotype , n = 147 , 45 % of the population ) , bupropion produced significantly higher abstinence rates than placebo at the end of treatment ( 32.5 % vs. 14.3 % , p = .01 ) and at the 6-month follow-up ( 31.2 % vs. 12.9 % , p = .008 ) . In contrast ,  bupropion  was no more effective than placebo for smokers in the CYP2B6 * 1 group ( CYP2B6 * 1/*1 , n = 179 ) at the end of treatment ( 31.0 % vs. 31.6 % , p = .93 ) or at the 6-month follow-up ( 22.0 % vs. 21.5 % , p = .94 ) . There was a significant genotype by treatment interaction at the end of treatment ( odds ratio [ OR ] = 2.97 , confidence interval [ CI ] = 1.05 - 8.40 , p = .04 ) , which was similar at 6-month follow-up ( OR = 2.98 , CI = .98 - 9.06 , p = .05 ) . CONCLUSIONS These data suggest that smokers with the CYP2B6 * 6 genotype have a higher liability to relapse on placebo and that they may be good c and i date s for bupropion treatment for smoking cessation
Results : We confirmed the importance of the 4 main factors influencing SC : ( 1 ) environmental factors , ( 2 ) genomic factors , ( 3 ) gene-environment interactions , and ( 4 ) evidence -based interventions .
The model demonstrates the complex network of factors influencing SC .
Background : Smoking behaviour is a major public health problem worldwide .
Several sources have confirmed the implication of genomic factors in smoking behaviour .
These factors interact both with environmental factors and interventions to develop a certain behaviour .
Objectives : Describing the environmental and genomic factors as well as the interventions influencing smoking cessation  ( SC ) and developing a working model incorporating the different factors influencing SC were our main objectives .