Longitudinal study of long-term smoking behaviour by biomarker-supported determination of exposure to smoke

Saliva Liquid Biopsy for Point-of-Care Applications

Saliva is a non-invasive biofluid, which is easy to collect, transport, and store. Because of its accessibility and connection to systemic diseases, saliva is one of the best candidates for the advancement of point-of-care medicine, where individuals are able to easily monitor their health status by using portable convenient tools such as smartphones. There are a variety of scenarios with which saliva can be used: studies have been conducted on using saliva to measure stress hormones, enzyme levels, developmental disease biomarkers, and even cancer mutations. If validated biomarkers were combined with high-quality detection tools, saliva would open up a new frontier in high-quality healthcare, allowing physicians and patients to work together for real-time health monitoring and high-impact personalized preventative medicine. One of the most exciting emerging frontiers of saliva is liquid biopsy, which is a non-invasive means to assess the presence and characteristics of cancer in a patient. This article will review current basic knowledge of biomarkers, review their relation to different diseases and conditions, and explore liquid biopsy for point-of-care applications.

Reference change values in concentrations of urinary and salivary biomarkers of exposure and mouth level exposure in individuals participating in an ambulatory smoking study

Background

Modified-risk tobacco products (MRTPs) are being developed that may contribute to tobacco harm reduction. To support reduced exposure or risk claims, a scientific framework needs to be developed to assess the validity of claims and monitor consumers after product launch. We calculated reference change values (RCVs) for biomarker of exposure (BoE): salivary cotinine and hydroxycotinine; and urinary total nicotine equivalents, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) and creatinine. Mouth-level exposure (MLE) to nicotine and tar were also recorded in an ambulatory setting to characterise variation among smokers in their everyday environment.

Methods

This non-residential, observational study was conducted over 3.5 years across 10 sites in Germany. Smokers of the same commercial 10 mg ISO tar product were included in the study (N=1011). Urine samples, questionnaires and cigarette filters were collected every 6 months for a total of seven timepoints.

Results

Greater variability in BoEs was observed compared with confined clinical studies. Gaussian distributed data showed 2-sided values over 100%, which are uninformative for decreases. The proportion of significant changes increased slightly among switchers, probably as a result of additional variability due to the range of products used post-switching. Overall proportions of changes remained small, consistent with literature reporting that when switching to a different tar yield cigarette, smokers partially compensate by changing their smoking behaviour.

Conclusion

Variability estimates and RCVs can be useful for monitoring subjects' BoE and MLE endpoints in longitudinal smoking studies where subjects are followed in their own environment and to aid sample size calculation of studies involving these endpoints.

Cigarette Smoking and Skin Prick Test in Patients With Allergic Rhinitis

Background:

Allergic Rhinitis (AR) is the most common allergic disease, affecting 30% of population around the world. The disease is predominantly associated with exposure to some aeroallergens like cigarette smoking. Skin Prick Test (SPT) is a method of detecting immediate allergic reactions and is applied for controlling disease and therapeutic modality.

Objectives:

This study was designed to investigate the effect of cigarette smoking on SPT results among male and female individuals with AR disease.

Patients and Methods:

A total of 478 patients with AR admitted to the 2 main hospitals of Zahedan City from 2005 to 2012, were recruited in this analytic-descriptive study. Categories of smokers and never smokers were used based on patient’s statements and their history of smoking. SPT was performed with panel of some allergens and results were recorded and analyzed statistically. Odds ratio and confidence interval method were calculated using univariate logistic regression.

Results:

The results of this study indicated that 41.4% of patients with allergic rhinitis was smoker with ages ranged from 15 to 70 years. The result of this study also showed that smoking has no effect on SPT results of pollen and weeds aeroallergens conducted on male and female AR patients. However, male were significantly more sensitive than female in terms of sensitivity to the aspergillus, cladosporium, house dust mite, grasses, wheat, cockroach, and feather allergens.

Conclusions:

Our findings did not support the effect of cigarette smoking on SPT reactivity to pollen and weeds aeroallergens. However, male were significantly more sensitive than female in terms of sensitivity to some allergens.

A longitudinal study of smokers' exposure to cigarette smoke and the effects of spontaneous product switching

A challenge in investigating the effect of public health policies on cigarette consumption and exposure arises from variation in a smoker's exposure from cigarette to cigarette and the considerable differences between smokers. In addition, limited data are available on the effects of spontaneous product switching on a smoker's cigarette consumption and exposure to smoke constituents. Over 1000 adult smokers of the same commercial 10mg International Organization for Standardization (ISO) tar yield cigarette were recruited into the non-residential, longitudinal study across 10 cities in Germany. Cigarette consumption, mouth level exposure to tar and nicotine and biomarkers of exposure to nicotine and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone were measured every 6months over a 3 and a half year period. Cigarette consumption remained stable through the study period and did not vary significantly when smokers spontaneously switched products. Mouth level exposure decreased for smokers (n=111) who switched to cigarettes of 7mg ISO tar yield or lower. In addition, downward trends in mouth level exposure estimates were observed for smokers who did not switch cigarettes. Data from this study illustrate some of the challenges in measuring smokers' long-term exposure to smoke constituents in their everyday environment.