Breath carbon monoxide and semiquantitative saliva cotinine as biomarkers for smoking.
OBJECTIVE
As a biomarker of smoking, semiquantitative analysis of cotinine (NicAlert) offers several advantages over breath carbon monoxide (CO) and quantitative analysis of cotinine. Recent studies have used urine NicAlert and breath CO in combination to verify abstinence. However, no studies have evaluated the performance of saliva NicAlert against or in combination with breath CO.


METHODS
Breath CO, saliva NicAlert, and smoking history were compared in an urban population of daily smokers (n = 24) and nonsmokers (n = 25).


RESULTS
Saliva NicAlert predicted self-reported smoking with 100% sensitivity and 96% specificity. At a cutoff of > 5 ppm, breath CO had 100% sensitivity and 100% specificity in predicting self-reported smoking. Breath CO was positively correlated with saliva NicAlert and negatively correlated with minutes since last cigarette.


CONCLUSIONS
Saliva NicAlert had high sensitivity and specificity in identifying daily smokers. Compared to saliva NicAlert, breath CO level was more indicative of recent smoking. Future treatment studies should evaluate the performance of saliva NicAlert as an alternative to the urine test.
Marrone
Gina F
GF
Nicotine Psychopharmacology Section, Intramural Research Program, National Institute on Drug Abuse, Baltimore, MD, USA.
Paulpillai
Mane
M
Evans
Rebecca J
RJ
Singleton
Edward G
EG
Heishman
Stephen J
SJ
D000328:Adult; D015415:Biomarkers / Q000032:analysis; D001944:Breath Tests; D002248:Carbon Monoxide / Q000032:analysis*; D003367:Cotinine / Q000032:analysis*; D005260:Female; D006801:Humans; D007118:Immunoassay / Q000379:methods; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D012119:Respiration; D012463:Saliva / Q000378:metabolism*; D012680:Sensitivity and Specificity; D012907:Smoking / Q000378:metabolism* / Q000503:physiopathology
D015415:Biomarkers; D002248:Carbon Monoxide; D003367:Cotinine