Racial Differences in Hair Nicotine Concentrations Among Smokers

Environmental risk factors for the development of oral squamous cell carcinoma in cats

BACKGROUND

Risk factors for oral squamous cell carcinoma (OSCC) in cats are derived from a single study dated almost 20 years ago. The relationship between inflammation of oral tissues and OSCC is still unclear.

OBJECTIVES

To investigate previously proposed and novel potential risk factors for OSCC development, including oral inflammatory diseases.

ANIMALS

Hundred cats with OSCC, 70 cats with chronic gingivostomatitis (CGS), 63 cats with periodontal disease (PD), and 500 controls.

METHODS

Prospective, observational case-control study. Cats with OSCC were compared with an age-matched control sample of client-owned cats and cats with CGS or PD. Owners of cats completed an anonymous questionnaire including demographic, environmental and lifestyle information.

RESULTS

On multivariable logistic regression, covariates significantly associated with an increased risk of OSCC were rural environment (OR: 1.77; 95% CI: 1.03-3.04; P = .04), outdoor access (OR: 1.68; 95% CI: 1.07-2.63; P = .02), environmental tobacco smoke (OR: 1.77; 95% CI: 1.05-3; P = .03), and petfood containing chemical additives (OR: 1.98; 95% CI: 1.04-3.76; P = .04). Risk factors shared with CGS and PD were outdoor access and petfood containing chemical additives, respectively. A history of oral inflammation was reported in 35% of cats with OSCC but did not emerge as a risk factor.

CONCLUSIONS AND CLINICAL IMPORTANCE

The study proposes novel potential risk factors for OSCC in cats. Although a history of inflammatory oral disease was not significantly more frequent compared with random age-matched controls, OSCC shared several risk factors with CGS and PD.

Hair and nail nicotine levels of mothers and their infants as valid biomarkers of exposure to intrauterine tobacco smoke

INTRODUCTION

Tobacco use remains the single most modifiable cause of adverse pregnancy outcomes. It is crucial to be able to accurately quantify the burden of tobacco exposure on both the mother and fetus to have better measures of efficacy with interventions being studied.

METHODS

This is a descriptive and exploratory study conducted within a randomized controlled trial. Pregnant smoking and non-smoking women were followed from ≤22 weeks' gestation through delivery with monthly maternal smoking questionnaires, urine cotinine levels, and collection of maternal and infant hair and nail samples, at delivery. Nicotine was extracted and measured (ng/mg) using high-performance liquid chromatography with electrochemical detection.

RESULTS

Forty-six mother-infant dyads (34 pregnant smokers and 12 pregnant non-smokers) had successful completion of maternal and infant hair and nails samples. The median hair nicotine levels of the smoking mothers and their infants was significantly higher than those of the non-smokers (1.015 vs 0.037 ng/ mg, p<0.05 for the mothers; 0.445 vs 0.080 ng/mg, p<0.01 for the infants). Similarly, the median nail nicotine levels for smoking mothers and their infants were significantly higher than the non-smokers (2.130 vs 0.056 ng/mg, p<0.01 for the mothers; 0.594 vs 0.132 ng/mg, p<0.05 for the infants). We found a moderate but significant correlation between maternal hair and nail nicotine (r=0.64, p<0.001), infant hair and nail nicotine (r=0.64; p<0.001), maternal and infant hair nicotine (r=0.61, p<0.001), and maternal and infant nail nicotine levels (r=0.58, p<0.001).

CONCLUSIONS

Our study shows that both infant hair and nail nicotine levels are valid biomarkers of intrauterine tobacco smoke exposure, and can be used to identify prenatal smoke exposure, correlating well with the level of maternal nicotine exposure.

Smoking Behaviors Among Tobacco-Using Parents of Hospitalized Children and Association With Child Cotinine Level

OBJECTIVES

Understanding patterns of parental tobacco use and their association with child exposure can help us target interventions more appropriately. We aimed to examine the association between parental smoking practices and cotinine levels of hospitalized children.

METHODS

This is a secondary analysis of data collected from parents of hospitalized children, recruited for a cessation intervention randomized controlled trial. Smoking parents were identified by using a medical record screening question. Parent-reported demographics and smoking habits were compared to child urine cotinine by using geometric means and log-transformed cotinine levels in multivariable linear regression analyses.

RESULTS

A total of 213 patients had complete baseline parent-interview and urine cotinine data. The median age was 4 (interquartile range: 1-9); 57% were boys; 56% were white, 12% were Black, and 23% were multiracial; 36% identified as Hispanic. Most families (54%) had 1 smoker in the home; 36% had 2, and 9% had ≥3. Many (77%) reported having a ban on smoking in the home, and 86% reported smoking only outside. The geometric mean cotinine level of the cohort was 0.98 ng/mL. Higher cotinine levels were associated with more smokers in the home (ratio of 2.99) and smoking inside the house (ratio of 4.11).

CONCLUSIONS

Having more smokers in the home and parents who smoke inside are associated with increased smoke exposure; however, even children whose families who smoke only outside the home have significant levels of cotinine, a marker for toxin exposure.

Tanning Capacity and Nicotine Dependence Among African Americans

PURPOSE

Recent findings suggest a link between facultative melanin and nicotine dependence among African Americans. We hypothesized that tanning capacity is associated with the time to first cigarette (TTFC) of the day.

METHODS

Using a criterion based sample of 150 adult African American current smokers, reflectometer measures of constitutive and facultative melanin, tanning capacity, smoking status and history, saliva cotinine, sociodemographic characteristics, and stress and discrimination scales were recorded. TTFC was categorized as: 1) within the first 5 min versus more than 5 min; and 2) within the first 30 min versus more than 30 min. Descriptive and multivariate analyses were conducted.

RESULTS

Analysis revealed significantly higher tanning capacity among individuals who smoked their first cigarette of the day within the first 5 min of awakening (13.5) than among those who smoked after 5 min (10.3, p = 0.01) and among those who smoked within the first 30 min (12.8 vs. 9.6, p = 0.03) compared to those who initiated after this time point. Multivariate logistic regression indicated that tanning capacity was significantly and positively related (OR = 1.14, 95% CI = 1.05-1.22) to TTFC within the first 5 min and was also significantly related to TTFC within the first 30 min (OR = 1.13, CI = 1.03-1.23).

CONCLUSION

Tanning capacity was positively associated with a behavioral measure of nicotine dependence among African American smokers. This association was consistent whether comparing smokers at higher or lower levels of dependence. Future research should examine tanning capacity and other indicators of melanin content with smoking cessation rates and tobacco-attributable health disparities.

Smoking Topography among Korean Smokers: Intensive Smoking Behavior with Larger Puff Volume and Shorter Interpuff Interval

The difference of smoker’s topography has been found to be a function many factors, including sex, personality, nicotine yield, cigarette type (i.e., flavored versus non-flavored) and ethnicity. We evaluated the puffing behaviors of Korean smokers and its association with smoking-related biomarker levels. A sample of 300 participants was randomly recruited from metropolitan areas in South Korea. Topography measures during a 24-hour period were obtained using a CReSS pocket device. Korean male smokers smoked two puffs less per cigarette compared to female smokers (15.0 (13.0–19.0) vs. 17.5 (15.0–21.0) as the median (Interquartile range)), but had a significantly larger puff volume (62.7 (52.7–75.5) mL vs. 53.5 (42.0–64.2) mL); p = 0.012). The interpuff interval was similar between men and women (8.9 (6.5–11.2) s vs. 8.3 (6.2–11.0) s; p = 0.122) but much shorter than other study results. A dose-response association (p = 0.0011) was observed between daily total puff volumes and urinary cotinine concentrations, after controlling for sex, age, household income level and nicotine addiction level. An understanding of the difference of topography measures, particularly the larger puff volume and shorter interpuff interval of Korean smokers, may help to overcome a potential underestimation of internal doses of hazardous byproducts of smoking.

Hair nicotine concentration measurement in cats and its relationship to owner-reported environmental tobacco smoke exposure

OBJECTIVES

To investigate the association between hair nicotine concentration in cats and owner-reported exposure to environmental tobacco smoke.

MATERIALS AND METHODS

Owner questionnaires documented exposure. Nicotine was extracted from hair by sonification in methanol followed by hydrophilic interaction chromatography with mass spectrometry. Relationships between hair nicotine concentration and owner-reported exposure were examined using hypothesis-testing statistics and receiver operating characteristic curve analysis.

RESULTS

The hair nicotine concentration of reportedly exposed cats was significantly higher than unexposed cats and groups of cats with different levels of exposure had significantly different median hair nicotine concentrations corresponding to exposure. A hair nicotine concentration of 0·1 ng/mg had a specificity of 98% (95% confidence interval: 83 to 100) and a sensitivity of 69% (95% confidence interval: 54 to 84) for detecting environmental tobacco smoke exposure. Outdoors access, coat colour, urban or rural environment and length of time living with the owner were not obviously associated with hair nicotine concentration.

CLINICAL SIGNIFICANCE

Feline hair nicotine concentration appears strongly associated with owner-reported environmental tobacco smoke exposure. Feline hair nicotine concentration could therefore be used as a biomarker for tobacco smoke exposure, allowing future studies to assess whether exposed cats have an increased risk of specific diseases.

Racial differences in heritability of cigarette smoking in adolescents and young adults

INTRODUCTION

Although epidemiologic studies suggest low levels of cigarette use among African American adolescents relative to White U.S. adolescents, it is not known whether this may be due to racial differences in the relative contribution of genes and environment to cigarette use initiation and progression to regular use.

METHODS

Using data from White (n=2665) and African American (n=809) twins and full siblings sampled in the National Longitudinal Study of Adolescents, we fitted age-, sex- and race-specific variance decomposition models to estimate the magnitude of genetic and environmental effects on cigarette use initiation and cigarette use quantity in Whites and African Americans across adolescence and adulthood. We employ a causal-contingent-common pathway model to estimate the amount of variance explained in quantity of cigarettes smoked contingent on cigarette use initiation.

RESULTS

African Americans had lower cigarette use prevalence from adolescence through adulthood, and used cigarettes less heavily than Whites. Race-specific causal-contingent-common pathway models indicate that racial differences in genetic and environmental contributions to cigarette use initiation and cigarette use quantities are not present in adolescence but appear in young adulthood. Additive genetic factors were an important risk factor for cigarette use initiation for White but not African American young adults and adults.

CONCLUSIONS

Genetic and environmental contributions for cigarette use are similar by race in adolescence. In adulthood, genes have a stronger influence for cigarette use among White adolescents while the influence of the environment is minimal. For African Americans, both genetic and environmental influences are important in young adulthood and adulthood.

Effect of nicotine on melanogenesis and antioxidant status in HEMn-LP melanocytes

Nicotine is a natural ingredient of tobacco plants and is responsible for the addictive properties of tobacco. Nowadays nicotine is also commonly used as a form of smoking cessation therapy. It is suggested that nicotine may be accumulated in human tissues containing melanin. This may in turn affect biochemical processes in human cells producing melanin. The aim of this study was to examine the effect of nicotine on melanogenesis and antioxidant status in cultured normal human melanocytes HEMn-LP. Nicotine induced concentration-dependent loss in melanocytes viability. The value of EC50 was determined to be 7.43 mM. Nicotine inhibited a melanization process in human light pigmented melanocytes and caused alterations of antioxidant defense system. Significant changes in cellular antioxidant enzymes: superoxide dismutase and catalase activities and in hydrogen peroxide content were stated. The obtained results may explain a potential influence of nicotine on biochemical processes in melanocytes in vivo during long term exposition to nicotine.

A Norwegian study of the suitability of hair samples in epidemiological research of alcohol, nicotine and drug use

A feasibility study was performed to examine the effectiveness of hair testing in determining the prevalence of drug use in a young adult population. The study included 200 randomly selected young adults in Norway. It was designed to make the collection, preparation and analysis of the samples as little resource demaning as possible. Full anonymity was provided for the participants. In total, 23.5% of the samples were positive for one or more substances (14.5%, excluding the nicotine metabolite cotinine). Of the samples, 5% were positive for at least one illegal drug, 9.5% for a medicinal drug, 11.5% for cotinine and 2.5% for the alcohol metabolite ethyl glucuronide. The preliminary findings suggest that the study protocol used to collect and analyze the samples was unable to produce results that could be generalized to the young adult population in Norway. Analysis of hair samples may underestimate the use of cannabis, alcohol, amphetamine and methamphetamine. It may, however, be done to estimate cocaine and general drug use if a sample-collection procedure different from that described in our study is used and includes information about hair length, sample length, length from the scalp, cosmetic treatment, washing and whether the samples always get washed/decontaminated prior to analysis.