title: Nicotine Metabolite Ratio Is Associated With Lozenge Use But Not Quitting in Smokeless Tobacco Users.
abstract: BACKGROUND
  The nicotine metabolite ratio (NMR) of 3'-hydroxycotinine to cotinine is a noninvasive marker of the rate of nicotine metabolism. Fast metabolism (ie, a high NMR) is associated with lower cigarette smoking abstinence rates using transdermal nicotine replacement. We evaluated whether the NMR can be used to predict self-reported nicotine lozenge use and tobacco abstinence among smokeless tobacco users treated for tobacco dependence.
  
  
  METHODS
  This was a secondary analysis of data from one arm of a large trial. Participants received quitting support materials and 4-mg nicotine lozenges by mail plus three coaching phone calls. Saliva kits were mailed for collection of saliva samples, which were analyzed for cotinine and 3'-hydroxycotinine. Self-reported tobacco and lozenge use were assessed at 3 months. Analyses were performed using Spearman rank correlation and logistic regression.
  
  
  RESULTS
  Of the 160 saliva collection kits mailed, 152 were returned. The NMR was not significantly correlated with the baseline amount of smokeless tobacco used, the number of years of tobacco use, or the level of tobacco dependence as measured by the Severson Smokeless Tobacco Dependency Scale. The NMR was positively correlated with lozenge use (r = 0.21, P = .015), but it did not predict self-reported 7-day point prevalence abstinence at 3 months.
  
  
  CONCLUSIONS
  Fast metabolizers may need to self-administer more nicotine replacement in the form of nicotine lozenges to achieve the same clinical response achieved by slower metabolizers using fewer lozenges.
authors.affiliation: Primary Care Internal Medicine, Mayo Clinic College of Medicine, Rochester, MN; ebbert.jon@mayo.edu.
authors.forename: Jon O
authors.initials: JO
authors.lastname: Ebbert
authors.affiliation: Department of Psychology, Oregon Research Institute, Eugene, OR;
authors.forename: Herbert H
authors.initials: HH
authors.lastname: Severson
authors.affiliation: Department of Psychology, Oregon Research Institute, Eugene, OR;
authors.forename: Brian G
authors.initials: BG
authors.lastname: Danaher
authors.affiliation: Division of Clinical Pharmacology and Experimental Therapeutics, University of California, San Francisco, CA.
authors.forename: Neal L
authors.initials: NL
authors.lastname: Benowitz
authors.affiliation: Primary Care Internal Medicine, Mayo Clinic College of Medicine, Rochester, MN;
authors.forename: Darrell R
authors.initials: DR
authors.lastname: Schroeder
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D000368:Aged; D003367:Cotinine / Q000031:analogs & derivatives / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009538:Nicotine / Q000008:administration & dosage* / Q000378:metabolism*; D012463:Saliva / Q000378:metabolism; D020340:Tobacco Use Cessation / Q000379:methods*; D061485:Tobacco Use Cessation Devices; D014029:Tobacco Use Disorder / Q000188:drug therapy / Q000378:metabolism*; D014030:Tobacco, Smokeless; D055815:Young Adult
chemical_list: C001381:hydroxycotinine; D009538:Nicotine; D003367:Cotinine