Environmental tobacco smoke exposure, respiratory and cardiovascular health in restaurant and bar workers in Mexico

Environmental tobacco smoke (ETS) is a well established health hazard, being causally associated to lung cancer and cardiovascular disease. ETS regulations have been developed worldwide to reduce or eliminate exposure in most public places. Restaurants and bars constitute an exception. Restaurants and bar workers experience the highest ETS exposure levels across several occupations, with correspondingly increased health risks. In Mexico, previous exposure assessment in restaurants and bars showed concentrations in bars and restaurants to be the highest across different public and workplaces. Recently, Mexico developed at the federal level the General Law for Tobacco Control restricting indoors smoking to separated areas. AT the local level Mexico City developed the Law for the Protection of Non-smokers Health, completely banning smoking in restaurants and bars. Studies to assess ETS exposure in restaurants and bars, along with potential health effects were required to evaluate the impact of these legislative changes and to set a baseline measurement for future evaluations.^ A large cross-sectional study conducted in restaurants and bars from four Mexican cities was conducted from July to October 2008, to evaluate the following aims: Aim 1) Explore the potential impact of the Mexico City ban on ETS concentrations through comparison of Mexico City with other cities. Aim 2). Explore the association between ETS exposure, respiratory function indicators and respiratory symptoms. Aim 3). Explore the association between ETS exposure and blood pressure and heart rate.^ Three cities with no smoking ban were selected: Colima (11.5% smoking prevalence), Cuernavaca (21.5% smoking prevalence) and Toluca (27.8% smoking prevalence). Mexico City (27.9% smoking prevalence), the only city with a ban at the time of the study, was also selected. Restaurants and bars were randomly selected from municipal records. A goal of 26 restaurants and 26 bars per city was set, 50% of them under 100 m2. Each establishment was visited during the highest occupancy shift, and managers and workers answered to a questionnaire. Vapor-phase nicotine was measured using passive monitors, that were activated at the beginning and deactivated at the end of the shift. Also, workers participated at the beginning and end of the shift in a short physical evaluation, comprising the measurement of Forced Expiratory Volume in the first second (FEV1) and Peak Expiratory Flow (PEF), as well as blood pressure and heart rate.^ A total of 371 establishments were invited, 219 agreed to participate for a 60.1% participation rate. In them, 828 workers were invited, 633 agreed to participate for a 76% participation rate. Mexico City had at least 4 times less nicotine compared to any of the other cities. Differences between Mexico City and other cities were not explained by establishment characteristics, such as ventilation or air extraction. However, differences between cities disappeared when ban mechanisms, such as policy towards costumer's smoking, were considered in the models. An association between ETS exposure and respiratory symptoms (cough OR=1.27, 95%CI=1.04, 1.55) and respiratory illness (asthma OR=1.97, 95%CI=1.20, 3.24; respiratory illness OR=1.79, 95%CI=1.10, 2.94) was observed. No association between ETS and phlegm, wheezing or respiratory infections was observed. No association between ETS and any of the spirometric indicators was observed. An association between ETS exposure and increased systolic and diastolic blood pressure at the end of the shift was observed among non-smokers (systolic blood pressure beta=1.51, 95%CI=0.44, 2.58; diastolic blood pressure beta=1.50, 95%CI=0.72, 2.28). The opposite effect was observed in heavy smokers, were increased ETS exposure was associated with lower blood pressure at the end of the shift (systolic blood pressure beta=1.90, 95%CI=-3.57, -0.23; diastolic blood pressure beta=-1.46, 95%CI=-2.72, -0.02). No association in light smokers was observed. No association for heart rate was observed. ^ Results from this dissertation suggest Mexico City's smoking ban has had a larger impact on ETS exposure. Ventilation or air extraction, mechanisms of ETS control suggested frequently by tobacco companies to avoid smoking bans were not associated with ETS exposure. This dissertation suggests ETS exposure could be linked to changes in blood pressure and to increased respiratory symptoms. Evidence derived from this dissertation points to the potential negative health effects of ETS exposure in restaurants and bars, and provides support for the development of total smoking bans in this economic sector. ^

Predicting smokeless tobacco cessation in a blue -collar population

The use of smokeless tobacco products is undergoing an alarming resurgence in the United States. Several national surveys have reported a higher prevalence of use among those employed in blue-collar occupations. National objectives now target this group for health promotion programs which reduce the health risks associated with tobacco use.^ Drawn from a larger data set measuring health behaviors, this cross-sectional study tested the applicability of two related theories, the Theory of Reasoned Action (TRA) and the Theory of Planned Behavior (TPB), to smokeless tobacco (SLT) cessation in a blue-collar population of gas pipeline workers. In order to understand the determinants of SLT cessation, measures were obtained of demographic and normative characteristics of the population and specific constructs. Attitude toward the act of quitting (AACT) and subjective norm (SN) are constructs common to both models, perceived behavioral control (PBC) is unique to the TPB, and the number of past quit attempts is not contained in either model. In addition, a self-reported measure was taken of SLT use at two-month follow-up.^ The study population was comprised of all male SLT users who were field employees in a large gas pipeline company with gas compressor stations extending from Texas to the Canadian border. At baseline, 199 employees responded to the SLT portion of the survey, 118 completed some portion of the two-month follow-up, and 101 could be matched across time.^ As hypothesized, significant correlations were found between constructs antecedent to AACT and SN, although crossover effects occurred. Significant differences were found between SLT cessation intenders and non-intenders with regard to their personal and normative beliefs about quitting as well as their outcome expectancies and motivation to comply with others' beliefs. These differences occurred in the expected direction, with the mean intender score consistently higher than that of the non-intender.^ Contrary to hypothesis, AACT predicted intention to quit but SN did not. However, confirmatory of the TPB, PBC, operationalized as self-efficacy, independently contributed to the prediction of intention. Statistically significant relationships were not found between intention, perceived behavioral control, their interactive effects, and use behavior at two-month follow-up. The introduction of number of quit attempts into the logistic regression model resulted in insignificant findings for independent and interactive effects.^ The findings from this study are discussed in relation to their implications for program development and practice, especially within the worksite. In order to confirm and extend the findings of this investigation, recommendations for future research are also discussed. ^