title: The effect of catechol-O-methyltransferase Met/Val functional polymorphism on smoking cessation: retrospective and prospective analyses in a cohort study.
abstract: OBJECTIVE
  The Met/Val functional polymorphism of the gene-encoding catechol-O-methyltransferase (COMT) is one of the most widely tested variants for association with different phenotypes of addictive behavior, but replication has been inconsistent for smoking status. We investigated the relationship of this COMT single nucleotide polymorphism with smoking cessation in elderly persons in retrospective and prospective analyses.
  
  
  METHODS
  The study is embedded in the population-based Rotterdam Study cohort and included 5,115 persons aged 55 years and more. In the retrospective analyses using logistic regression, current smokers who had smoked 10 or more cigarettes daily for 10 or more years were compared with former smokers. In the prospective analyses, we followed 1,195 current smokers up to 12 years and used Cox proportional hazard model to detect the effect of the COMT single nucleotide polymorphism on self-reported incidence of smoking cessation.
  
  
  RESULTS
  The Val/Val genotype of COMT had a consistent association with smoking cessation as compared with the Met/Met+Met/Val genotypes in retrospective [odds ratio=0.79, 95% confidence interval (CI): 0.66-0.96, P=0.02] and prospective analyses (hazard ratio=0.80, 95% CI: 0.63-1.01, P=0.06). In the pooled analyses of prevalent and incident cessation cases that we compared with persisting smokers, the odds ratio was 0.70 (95% CI: 0.55-0.88, P=0.003). No sex difference and no effect of the COMT polymorphism on smoking initiation were observed.
  
  
  CONCLUSIONS
  Our results suggest that COMT Met/Val polymorphism is strongly associated with smoking cessation. The Met allele is the risk allele that decreases the likelihood of smoking cessation in men and women.
authors.affiliation: Department of Epidemiology, Erasmus MC, Rotterdam, The Netherlands.
authors.forename: Maryam
authors.initials: M
authors.lastname: Omidvar
authors.forename: Lisette
authors.initials: L
authors.lastname: Stolk
authors.forename: Andre G
authors.initials: AG
authors.lastname: Uitterlinden
authors.forename: Albert
authors.initials: A
authors.lastname: Hofman
authors.forename: Cornelia M
authors.initials: CM
authors.lastname: Van Duijn
authors.forename: Henning
authors.initials: H
authors.lastname: Tiemeier
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019943:Amino Acid Substitution; D001483:Base Sequence; D002394:Catechol O-Methyltransferase / Q000235:genetics*; D015331:Cohort Studies; D017931:DNA Primers / Q000235:genetics; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010597:Pharmacogenetics; D020641:Polymorphism, Single Nucleotide; D011446:Prospective Studies; D012189:Retrospective Studies; D012307:Risk Factors; D012907:Smoking / Q000235:genetics; D016540:Smoking Cessation
chemical_list: D017931:DNA Primers; D002394:Catechol O-Methyltransferase