Plasma concentrations of persistent organic pollutants and pancreatic cancer risk.

BACKGROUND: Findings and limitations of previous studies on persistent organic pollutants (POPs) and pancreatic cancer risk support conducting further research in prospective cohorts. METHODS: We conducted a prospective case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Participants were 513 pancreatic cancer cases and 1020 matched controls. Concentrations of 22 POPs were measured in plasma collected at baseline. RESULTS: Some associations were observed at higher concentrations of p, p'-DDT, trans-nonachlor, ß-hexachlorocyclohexane and the sum of six organochlorine pesticides and of 16 POPs. The odds ratio (OR) for the upper quartile of trans-nonachlor was 1.55 (95% confidence interval 1.06-2.26; P for trend = 0.025). Associations were stronger in the groups predefined as most valid (participants having fasted >6 h, with microscopic diagnostic confirmation, normal weight, and never smokers), and as most relevant (follow-up ≥10 years). Among participants having fasted >6 h, the ORs were relevant for 10 of 11 exposures. Higher ORs were also observed among cases with microscopic confirmation than in cases with a clinical diagnosis, and among normal-weight participants than in the rest of participants. Among participants with a follow-up ≥10 years, estimates were higher than in participants with a shorter follow-up (for trans-nonachlor: OR = 2.14, 1.01 to 4.53, P for trend = 0.035). Overall, trans-nonachlor, three PCBs and the two sums of POPs were the exposures most clearly associated with pancreatic cancer risk. CONCLUSIONS: Individually or in combination, most of the 22 POPs analysed did not or only moderately increased the risk of pancreatic cancer.

Stages of change, smoking characteristics, and cotinine concentrations in smokers: setting priorities for smoking cessation.

OBJECTIVE: We assessed whether the salivary cotinine content of daily smokers varied with the readiness to quit and smoking characteristics. METHODS: This cross-sectional study was conducted in Barcelona, Spain (n=1245) in 2004-2005. We administered a questionnaire to assess smoking behaviour and collected saliva to determine the cotinine content. We determined the distribution of 278 adult daily smokers across different stages of change and categorised them by individual and smoking characteristics. We used medians and interquartile ranges (IQR) to relate cotinine concentrations to different stages of change, tobacco consumption, and nicotine dependence based on the Fagerström Test for Nicotine Dependence (FTND). RESULTS: Around 68%, 22%, and 11% of smokers were in precontemplation, contemplation, and preparation stages, respectively. A mean of 17.0 cigarettes was smoked daily, with no differences among stages of change. The median cotinine concentration was 151.3 ng/ml (IQR: 83.2-227.8 ng/ml), with no differences among stages of change. The cigarette consumption scores, FTND, and time to first cigarette of the day were positively associated with cotinine concentration. CONCLUSIONS: The cotinine concentration was similar among the stages of change, but varied within each stage according to the number of cigarettes smoked, time to first cigarette of the day, and nicotine dependence.

Association between time to first cigarette after waking up and salivary cotinine concentration.

INTRODUCTION: The time to first cigarette smoked after waking up appears to be a good predictor of plasma and urine cotinine levels; however, collection of blood and urine is difficult in population-based studies and may influence participation. We aimed to test whether time to first cigarette is associated with salivary cotinine. METHODS: We used data from a cross-sectional study on a representative sample of the general population of Barcelona, Spain. We gathered information on smoking by means of a questionnaire and collected saliva for cotinine analysis. Of 1,245 participants, 22.9% were daily smokers, and the final sample for analysis consisted of 210 daily smokers. RESULTS: There were significant associations between salivary cotinine and time to first cigarette, between cigarette consumption and time to first cigarette, and between salivary cotinine and cigarette consumption. Salivary cotinine had decreased as time to first cigarette increased. After adjusting for cigarette consumption and sex, there were significant differences in mean salivary cotinine according to time to first cigarette (≤ 5 min: 219.2 ng/ml; 6-30 min: 175.8 ng/ml; 31-60 min: 168.5 ng/ml; >60 min: 137.2 ng/ml). All paired comparisons were significant (p < .001) except in the 6- to 30-min group versus the 31- to 60-min group (p = .701). CONCLUSIONS: After adjustment for the number of cigarettes smoked in the last 24 hr, time to first cigarette is associated with salivary cotinine concentration.

Assessment of exposure to secondhand smoke by questionnaire and salivary cotinine in the general population of Barcelona, Spain (2004-2005).

OBJECTIVES: To estimate the prevalence of self-reported exposure to secondhand smoke (SHS) in different settings and to describe salivary cotinine concentration and its determinants among non-smokers. METHODS: Cross-sectional study of a representative sample (N=775) of adult non-smokers in Barcelona, Spain (years 2004-2005). We assessed exposure to SHS using a questionnaire and measurement of salivary cotinine concentration. We calculated prevalence rates of self-reported exposure and medians and geometric means of salivary cotinine concentration. We adjusted for potential confounding factors with multinomial logistic regression models. RESULTS: The prevalence rate of self-reported exposure to SHS among non-smokers in any setting was 75.7% (95% CI: 72.7%-78.8%). The prevalence of exposure to SHS tended to decrease with age. The geometric mean of cotinine concentrations among non-smokers was 1.49 ng/ml (95% CI: 1.39-1.60 ng/ml) among all subjects, and 1.80 ng/ml (95% CI: 1.37-2.35 ng/ml) in subjects who reported exposure to SHS in all settings. In bivariate and multivariate analyses, the cotinine concentration increased with the number of smokers and the number of cigarettes smoked per day in the presence of non-smokers in the household. CONCLUSIONS: In this population, self-reported exposure to SHS is very high. Salivary cotinine concentrations in non-smokers are associated with exposure at home.

Salivary cotinine concentrations in daily smokers in Barcelona, Spain: a cross-sectional study.

BACKGROUND: Characterizing and comparing the determinant of cotinine concentrations in different populations should facilitate a better understanding of smoking patterns and addiction. This study describes and characterizes determinants of salivary cotinine concentration in a sample of Spanish adult daily smoker men and women. METHODS: A cross-sectional study was carried out between March 2004 and December 2005 in a representative sample of 1245 people from the general population of Barcelona, Spain. A standard questionnaire was used to gather information on active tobacco smoking and passive exposure, and a saliva specimen was obtained to determine salivary cotinine concentration. Two hundred and eleven adult smokers (>16 years old) with complete data were included in the analysis. Determinants of cotinine concentrations were assessed using linear regression models. RESULTS: Salivary cotinine concentration was associated with the reported number of cigarettes smoked in the previous 24 hours (R2 = 0.339; p < 0.05). The inclusion of a quadratic component for number of cigarettes smoked in the regression analyses resulted in an improvement of the fit (R2 = 0.386; p < 0.05). Cotinine concentration differed significantly by sex, with men having higher levels. CONCLUSION: This study shows that salivary cotinine concentration is significantly associated with the number of cigarettes smoked and sex, but not with other smoking-related variables.

Nicotine depedence and salivary cotinine concentration in daily smokers.

There is scant information on nicotine dependence in smokers not seeking cessation treatment. This study analyses the relationship between nicotine dependence, measured by the Fagerström Test for Nicotine Dependence (FTND), and salivary cotinine concentration in a sample of smokers from the general population. We conducted a cross-sectional study (2004-2005) of a representative sample of the general population of Barcelona, Spain (n=1245). The analysis included 196 daily smokers aged more than 16 years. Information on smoking was obtained by questionnaire and cotinine concentration was determined in saliva. Geometric means of cotinine concentration by every single FTND item were computed, and multivariate linear regression was used to explore the relationship among these variables. Participants smoked a mean of 17.0 cigarettes per day, and the mean FTND score was 3.27 (95% confidence interval: 2.92-3.61). Around 17% of subjects (95% confidence interval: 12.0-22.5%) had high nicotine dependence. Cotinine concentration differed significantly by nicotine dependence levels. In a multiple linear regression model including the sum of the FTND items 2, 3, and 6, and the single FTND items 1, 4, and 5, adjusted for sex, the time to first cigarette after waking up (item 1), the number of cigarettes smoked daily (item 4), and smoking more in the first hours of the day (item 5) were significantly related to salivary cotinine concentration (R(2)=0.414). Salivary cotinine levels were associated with nicotine dependence as measured by the FTND, especially with the items on daily tobacco consumption, time to first cigarette after waking up, and smoking more in the first hours of the day.

The role of type of tobacco and type of alcoholic beverage in oral carcinogenesis.

Incidence rates of oral and oropharyngeal cancers (oral cancer) in Spain are among the highest in Europe. Spain has a population heavily exposed to various types of tobacco and alcoholic beverages but the role and impact of tobacco type and beverage type in oral carcinogenesis remain controversial. To estimate the independent and joint effects of tobacco smoking and alcohol drinking habits on the risk of developing oral cancer, we carried out a multicenter, hospital-based, case-control study in Spain. Data from 375 patients newly diagnosed with cancer of the oral cavity or oropharynx and 375 matched control subjects were analyzed using multivariate logistic regression procedures. All exposure characteristics of amount, duration and cessation of both tobacco smoking and alcohol drinking were strongly associated with cancer risk following a dose-dependent relationship. At equal intake or duration levels, black-tobacco smoking and drinking of spirits were both associated with a 2- to 4-fold increase in cancer risk compared to blond tobacco smoking or drinking of wine or beer, respectively. While ever exposure to smoking only or drinking only was associated with a moderate and nonsignificant increase in cancer risk, a history of simultaneous exposure to both habits was associated with a 13-fold increase that was compatible with a synergistic effect model (p-value for interaction: 0.008). Exposure to black tobacco smoking and/or drinking of spirits may account for up to 77% of oral cancer occurrence in Spain. Both black tobacco smoking and drinking of spirits place individuals at a very high risk of developing oral cancer. Simultaneous exposure to tobacco and alcohol consumption increases oral cancer risk in a synergistic fashion, even when consumption levels are moderate. These results underline the importance of type of tobacco and alcohol concentration in oral carcinogenesis.