Determinants of salivary cotinine concentrations in Chinese male smokers.
BACKGROUND
Identifying factors that affect cotinine levels in smokers may be useful for smoking cessation programs. Our aims were to characterize the distribution of salivary cotinine levels in Chinese smokers and to investigate factors that influence cotinine concentrations.


METHODS
In a cross-sectional study, 600 Chinese adult smokers answered a questionnaire on smoking habits and provided a saliva sample for cotinine analysis. Modification of the relation between number of cigarettes smoked and cotinine concentration by individual characteristics, smoking behavior, and type of tobacco was evaluated.


RESULTS
Quadratic model provided the best fit for the relation between number of cigarettes smoked in the previous 24 hours and salivary cotinine concentration. Among those smoking up to 20 cigarettes, the median cotinine concentration was higher among younger subjects, those smoking cigarettes without filter and regular rather than light cigarettes, and those inhaling frequently and deeply. Such trends were not observed among heavier smokers. The increase in cotinine per cigarette tended to be larger in those with lower median cotinine level.


CONCLUSIONS
Our findings show that smoking behavior-related factors modify the relation between number of cigarettes smoked and salivary cotinine concentration. This suggests that smokers may regulate their smoking behavior to achieve a certain optimum nicotine level.
Jaakkola
Maritta S
MS
Department of Epidemiology, Bloomberry School of Public Health, Johns Hopkins University, Baltimore, MD, USA. Maritta.Jaakkola@occuphealth.fi
Ma
Jiemin
J
Yang
Gonghuan
G
Chin
Ming Feng
MF
Benowitz
Neal L
NL
Ceraso
Marion
M
Samet
Jonathan M
JM
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D002681:China / Q000453:epidemiology; D003367:Cotinine / Q000032:analysis*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D015994:Incidence; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D011336:Probability; D012307:Risk Factors; D012463:Saliva / Q000737:chemistry*; D017678:Sex Distribution; D012907:Smoking / Q000453:epidemiology*; D011795:Surveys and Questionnaires; D014505:Urban Population
D003367:Cotinine