Lung deposition analyses of inhaled toxic aerosols in conventional and less harmful cigarette smoke: a review.

Int J Environ Res Public Health. 2013;10(9):4454-85

Authors: Kleinstreuer C, Feng Y

Abstract
Inhaled toxic aerosols of conventional cigarette smoke may impact not only the health of smokers, but also those exposed to second-stream smoke, especially children. Thus, less harmful cigarettes (LHCs), also called potential reduced exposure products (PREPs), or modified risk tobacco products (MRTP) have been designed by tobacco manufacturers to focus on the reduction of the concentration of carcinogenic components and toxicants in tobacco. However, some studies have pointed out that the new cigarette products may be actually more harmful than the conventional ones due to variations in puffing or post-puffing behavior, different physical and chemical characteristics of inhaled toxic aerosols, and longer exposure conditions. In order to understand the toxicological impact of tobacco smoke, it is essential for scientists, engineers and manufacturers to develop experiments, clinical investigations, and predictive numerical models for tracking the intake and deposition of toxicants of both LHCs and conventional cigarettes. Furthermore, to link inhaled toxicants to lung and other diseases, it is necessary to determine the physical mechanisms and parameters that have significant impacts on droplet/vapor transport and deposition. Complex mechanisms include droplet coagulation, hygroscopic growth, condensation and evaporation, vapor formation and changes in composition. Of interest are also different puffing behavior, smoke inlet conditions, subject geometries, and mass transfer of deposited material into systemic regions. This review article is intended to serve as an overview of contributions mainly published between 2009 and 2013, focusing on the potential health risks of toxicants in cigarette smoke, progress made in different approaches of impact analyses for inhaled toxic aerosols, as well as challenges and future directions.

PMID: 24065038 [PubMed - in process]

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Beyond Lung Cancer: A Strategic Approach to Interpreting Screening Computed Tomography Scans on the Basis of Mortality Data From the National Lung Screening Trial.

J Thorac Imaging. 2013 Sep 25;

Authors: Chiles C, Paul NS

Abstract
Low-dose computed tomography screening in older patients with a heavy-smoking history can be viewed as an opportunity to screen for smoking-related illnesses and not just for lung cancer. Within the National Lung Screening Trial, 24.1% of all deaths were attributed to lung cancer, but there were significant competing causes of mortality in this patient population. Cardiovascular illness caused 24.8% of deaths. Other neoplasms were listed as the cause of death in 22.3%, and respiratory illness was the cause of death in 10.4%. All of these illnesses might be attributed to smoking. Low-dose computed tomography of the thorax may provide information about these diseases, which could be used to guide therapeutic intervention and, hopefully, alter the courses of these diseases. Information about coronary artery calcification, chronic obstructive pulmonary disease, and potential extrapulmonary malignancy should be provided in the report of the screening examination. This must be balanced against the risk of the burden of false-positive findings and the costs, both psychological and financial, associated with additional investigative evaluations.

PMID: 24071622 [PubMed - as supplied by publisher]

Obesity in Bulgarian patients with chronic obstructive pulmonary disease.

Chron Respir Dis. 2013 Sep 26;

Authors: Dimov D, Tacheva T, Koychev A, Ilieva V, Prakova G, Vlaykova T

Abstract
It has been well defined that obesity is strongly linked with several respiratory symptoms and diseases, but no convincing evidence has been provided for chronic obstructive pulmonary disease (COPD). In the current study, we aim to assess the possible prevalence of obesity in patients with COPD in a cross-sectional case-control study of individuals from the region of Stara Zagora, Bulgaria, and to explore whether the body mass has some effect on the lung function of COPD patients. The study included 158 patients with COPD (Global Initiative for Chronic Obstructive Lung Disease (GOLD) II, III, and IV stages) and 123 individuals unaffected by the disease (control). A higher frequency of obesity compared to the controls (20.3%) was observed in patients with COPD (29.1%, p = 0.093), especially in those with GOLD II stage (37.7%, p = 0.009). Prevalence of obesity was highest in COPD GOLD II, followed by GOLD III and IV stages (p = 0.068). When diabetes was considered as confounding factor, we found a significant prevalence of obesity in COPD patients than the controls with diabetes (p = 0.031). Interestingly, there was a statistically significant moderate positive correlation between the body mass index and forced expiratory volume in one second as a percentage of predicted value in the whole patients' group (R = 0.295, p = 0.0002) as well as in the subgroups of GOLD II (R = 0.257, p = 0.024) and GOLD III COPD (R = 0.259, p = 0.031).The results of our study propose that the increased body mass, particularly obesity is frequent comorbidity to COPD, especially to less severe diseases. Moreover, the results suggest that the higher body weight may provide some protection against the impairment of lung functions in patients with stable COPD.

PMID: 24072750 [PubMed - as supplied by publisher]

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Is health-related quality of life associated with upper and lower airway inflammation in asthmatics?

Biomed Res Int. 2013;2013:539290

Authors: Scichilone N, Braido F, Taormina S, Pozzecco E, Paternò A, Baiardini I, Casolaro V, Canonica GW, Bellia V

Abstract
Background. Allergic diseases impair health-related quality of life (HR-QoL). However, the relationship between airway inflammation and HR-QoL in patients with asthma and rhinitis has not been fully investigated. We explored whether the inflammation of upper and lower airways is associated with HR-QoL. Methods. Twenty-two mild allergic asthmatics with concomitant rhinitis (10 males, 38 ± 17 years) were recruited. The Rhinasthma was used to identify HR-QoL, and the Asthma Control Test (ACT) was used to assess asthma control. Subjects underwent lung function and exhaled nitric oxide (eNO) test, collection of exhaled breath condensate (EBC), and nasal wash. Results. The Rhinasthma Global Summary score (GS) was 25 ± 11. No relationships were found between GS and markers of nasal allergic inflammation (% eosinophils: r = 0.34, P = 0.24; ECP: r = 0.06, P = 0.87) or bronchial inflammation (pH of the EBC: r = 0.12, P = 0.44; bronchial NO: r = 0.27, P = 0.22; alveolar NO: r = 0.38, P = 0.10). The mean ACT score was 18. When subjects were divided into controlled (ACT ≥ 20) and uncontrolled (ACT < 20), the alveolar NO significantly correlated with GS in uncontrolled asthmatics (r = 0.60, P = 0.04). Conclusions. Upper and lower airways inflammation appears unrelated to HR-QoL associated with respiratory symptoms. These preliminary findings suggest that, in uncontrolled asthma, peripheral airway inflammation could be responsible for impaired HR-QoL.

PMID: 24073408 [PubMed - in process]