Respiratory effects of tobacco smoking among young adults

Effects of Smoking and Physical Activity on the Pulmonary Function of Young University Nursing Students in Cáceres (Spain)

Background:

The simultaneous effect of physical activity (PA) and smoking on pulmonary function in young people remains unclear.

Propose:

The aim of this study was to determine the influence of smoking and PA on pulmonary function in young university students in Cáceres, Spain.

Methods:

A sample of 120 young nursing students was studied (60 smokers and 60 nonsmokers). All subjects underwent spirometry with a COPD-6 portable device, and their level of PA was quantified using the International Physical Activity Questionnaire. The influence of PA and smoking on pulmonary function was determined by comparing hypotheses.

Results:

Significant differences were observed between smokers and nonsmokers in terms of percent forced expiratory volume in 1 second, percent forced expiratory volume in 6 seconds, lung age, and the difference between lung age and chronological age (LA–CA) in those who practiced mild PA. In the subjects who performed moderate and vigorous PA, these differences were not noted. In the intragroup analysis, significant differences were observed in smokers in terms of percent forced expiratory volume in 1 second, percent forced expiratory volume in 6 seconds, lung age, and LA–CA; however, in the control group, differences were only observed in terms of lung age and LA–CA. These findings were confirmed in the multivariate analysis.

Conclusions/Implications for Practice:

Our findings confirmed a deterioration in pulmonary function in smokers who did not perform moderate or vigorous PA. The level of PA performed was positively related to pulmonary function in smokers, whereas in nonsmokers, improvements were only significant in LA–CA.

Accuracy of spirometry for detection of asthma: a cross-sectional study

BACKGROUND

Asthma is a chronic inflammatory disease with airway hyperresponsiveness. Spirometry is the most commonly used test among asthmatic patients. Another functional test used for diagnosing asthma is the bronchial challenge test. The aim of this study was to analyze the accuracy of spirometry for detecting asthma in the general population.

DESIGN AND SETTING

Cross-sectional study with data analysis to evaluate the accuracy of spirometry through calculating sensitivity, specificity and predictive values and through the kappa agreement test.

METHODS

Subjects who constituted a birth cohort were enrolled at the age of 23 to 25 years. Spirometric abnormality was defined as reduced forced expiratory volume in one second, i.e. lower than 80% of the predicted value. Measurement of bronchial responsiveness was performed by means of the bronchial challenge test with methacholine. The gold-standard diagnosis of asthma was defined as the presence of bronchial hyperresponsiveness in association with respiratory symptoms.

RESULTS

Asthma was detected in 200 subjects (10.4%) out of the sample of 1922 individuals. Spirometric abnormality was detected in 208 subjects (10.9%) of the sample. The specificity of spirometric abnormality for detecting asthma was 90%, sensitivity was 23%, positive predictive value was 22%, and negative predictive value was 91%. The kappa test revealed weak agreement of 0.13 (95% confidence interval, CI: 0.07-0.19) between spirometry and the diagnosis of asthma.

CONCLUSION

Spirometry, as a single test, has limitations for detecting asthma in the general population.

Pulmonary effects of active smoking and secondhand smoke exposure among adolescent students in Juárez, Mexico

BACKGROUND

Youth smoking trends among Latin American countries, including Mexico, are on the rise. Notably, although the high prevalence of smoking in teens has been well documented in the literature, few studies have evaluated the impact of smoking and secondhand smoke (SHS) exposure on their respiratory system.

OBJECTIVE

To investigate the effects of smoking and SHS exposure on the respiratory health and lung function among eighth-grade students in Juárez, Mexico.

METHODS

A cross-sectional study was undertaken on a sample of convenience. The study outcomes centered on evaluating 300 students' lung function by spirometry (forced expiratory volume in 1 second [FEV1], forced expiratory volume in 1 second/forced vital capacity ratio [FEV1/FVC], and forced mid-expiratory flow rate [FEF25%-75%]) and their respiratory health (smoking behavior and SHS exposure) by their self-reported responses to a standardized respiratory questionnaire. The study outcomes were compared among three distinct groups: 1) nonsmokers/nonexposed to SHS; 2) nonsmokers/exposed to SHS; and 3) smokers.

RESULTS

The majority of the study participants were 14 years old (85%), females (54%), who attended eighth grade in a public school setting (56%). Approximately, half reported being of low socioeconomic status (49%) and nonsmokers/exposed to SHS (49%). The lung function parameters of smokers were found to be lower (FEV1 =62.88±10.25; FEV1/FVC =83.50±14.15; and FEF25%-75% =66.35±12.55) than those recorded for the nonsmokers/exposed to SHS (FEV1 =69.41±11.35; FEV1/FVC =88.75±15.75; and FEF25%-75% =78.90±14.65) and significantly reduced when compared to the nonsmokers/nonexposed to SHS (FEV1 =79.14±13.61; FEV1/FVC =94.88±21.88; and FEF25%-75% =87.36±17.02) (P<0.001). Similarly, respiratory complaints were more prevalent among smokers and those exposed to SHS when compared to nonsmokers/nonexposed to SHS.

CONCLUSION

Our findings suggest that initiation of cigarette smoking and, to a lesser extent, exposure to SHS in adolescence leads to increased respiratory symptoms and reduction of pulmonary function test values. Public health initiatives that aim to prevent smoking initiation, assist in cessation, and lessen SHS exposure of adolescents need to be school-based and employed as early as middle school.

Bronchial hyperresponsiveness

BACKGROUND

Bronchial hyperresponsiveness (BHR) is often regarded as a 'hallmark' of asthma and bronchoprovocation testing is frequently performed to support a diagnosis of asthma. However, BHR is also found in a spectrum of other lung diseases and can be provoked by a variety of specific stimuli.

AIMS

To review the pathophysiology of BHR, discuss various methods of testing for BHR and describe the epidemiology of BHR in a variety of previously studied populations.

METHODS

We performed a systematic review of references identified using Medline and hand searches of identified articles. Because of space limitations, we have included those reports that seem most representative of the overall BHR literature.

RESULTS

BHR can be induced by a variety of stimuli that trigger a number of different but overlapping physiological mechanisms. Bronchoprovocation testing can be performed using a variety of stimuli, various protocols and differing test criteria, yielding results that may be discordant. Elevated rates of BHR have been reported in studies of smokers, chronic obstructive pulmonary disease patients, atopics, athletes, exposed workers and the general population.

CONCLUSIONS

Due to the prevalence of BHR in a spectrum of clinical patients and working populations, clinicians should be aware that BHR is not specific for asthma. When performed correctly, the greatest clinical value of BHR testing is to rule out suspected asthma in patients in whom testing is negative. Assessment of BHR also provides insights into the pathological mechanisms of airway disease.

Smoking status and health-related quality of life: a longitudinal study in young adults

PURPOSE

The possibility that tobacco use affects health-related quality of life (HRQoL) has attracted interest. However, a lack of prospective evidence weakens the case for a causal relationship. The aim was to examine the longitudinal relationship between change in smoking status and change in HRQoL in young adults.

METHODS

We conducted a population-based cohort study with data collected in 2004-2006 (aged 26-36) and 2009-2011 (aged 31-41). Exposure was change in self-reported smoking status during follow-up. Outcomes were changes in physical and mental HRQoL measured by SF-12.

RESULTS

For physical HRQoL (n = 2080), quitters had a 2.12 (95 % confidence interval (CI) 0.73, 3.51) point improvement than continuing smokers, whereas former smokers who resumed smoking had a 2.08 (95 % CI 0.21, 3.94) point reduction than those who maintained cessation. Resumed smokers were 39 % (95 % CI 10, 75 %) more likely to have a clinically significant (>5 point) reduction of physical HRQoL than former smokers who maintained cessation. In contrast, quitters were 43 % (95 % CI 3, 98 %) more likely to have a clinically significant (>5 point) improvement in physical HRQoL than continuing smokers. Change in smoking status was not significantly associated with change in mental HRQoL (n = 1788).

CONCLUSIONS

Smoking by young adults was cross-sectionally associated with lower physical HRQoL and longitudinally associated with reductions in physical HRQoL. The expectation of short- to medium-term gains in physical HRQoL as well as long-term health benefits may help motivate young adult smokers to quit.

Laboratory animals and respiratory allergies: the prevalence of allergies among laboratory animal workers and the need for prophylaxis

OBJECTIVE

Subjects exposed to laboratory animals are at a heightened risk of developing respiratory and allergic diseases. These diseases can be prevented by simple measures such as the use of personal protective equipment. We report here the primary findings of the Laboratory Animals and Respiratory Allergies Study regarding the prevalence of allergic diseases among laboratory animal workers, the routine use of preventive measures in laboratories and animal facilities, and the need for prevention programs.

METHODS

Animal handlers and non-animal handlers from 2 Brazilian universities (University of São Paulo and State University of Campinas) answered specific questionnaires to assess work conditions and symptoms. These subjects also underwent spirometry, a bronchial challenge test with mannitol, and skin prick tests for 11 common allergens and 5 occupational allergens (rat, mouse, guinea pig, hamster, and rabbit).

RESULTS

Four hundred fifty-five animal handlers (32±10 years old [mean±SD], 209 men) and 387 non-animal handlers (33±11 years old, 121 men) were evaluated. Sensitization to occupational allergens was higher among animal handlers (16%) than non-animal handlers (3%, p<0.01). Accessibility to personal protective equipment was measured at 85% (median, considering 73 workplaces of the animal handler group). Nineteen percent of the animal handlers indicated that they wear a respirator at all times while handling animals or working in the animal room, and only 25% of the animal handlers had received an orientation about animal-induced allergies, asthma, or rhinitis.

CONCLUSION

In conclusion, our data indicate that preventive programs are necessary. We suggest providing individual advice to workers associated with institutional programs to promote a safer work environment.

A review of the evidence on technology-based interventions for the treatment of tobacco dependence in college health

BACKGROUND

The college years are a critical time in the development of smoking behavior and tobacco use. Smoking is linked to 30% of cancer deaths, 80% of deaths from chronic obstructive pulmonary disease, and early cardiovascular disease and death. Effective cessation interventions at this time provide an opportunity to drastically reduce premature morbidity and mortality.

AIMS

To review available evidence on Internet interventions with young adults, including methodology, theoretical frameworks and outcome measures for tobacco treatment to guide the development of a program in college health.

METHODS

A comprehensive literature search for studies published from January 1999 to February 2011, in multiple databases was conducted, along with hand-searching of reference lists. Inclusion criteria were: participants aged 18-30 years, intervention involved the Internet through either Web sites or e-mail or texting, and outcome measurement of tobacco cessation/abstinence. Studies were evaluated utilizing a tool synthesized from guidelines presented by the Cochrane Collaboration.

FINDINGS

Eight studies met the inclusion criteria (four randomized controlled trials, four cohort studies). Theoretical frameworks utilized were the Transtheoretical Model of Change, Health Belief Model, Theory of Social Support, and social cognitive theory. Interventions varied and included computer-generated advice letters, Web-based cessation guides, computer-generated text messages, and peer e-mail support. With smoking abstinence as the primary outcome measure, there was a statistically significant improvement in quit rates. Because of the use of multiple components, differences in interventions and the number of contacts, it is not clear what types of computer-based applications are most effective. Small sample sizes, lack of control groups, and inconsistency in outcome measures limit the ability to provide conclusive evidence to support these interventions-but support the feasibility to use in the design of future programs.

CONCLUSIONS

Use of technology-based interventions, such as the Internet, may be an effective tool for tobacco treatment interventions, especially with college students. There is great potential to reach large numbers of students, many who may not identify themselves as smokers or seek traditional methods for treatment. Additional research is needed to determine which technology-based interventions are most effective and to provide more conclusive evidence.

Influence of asthma definition on the asthma-obesity relationship

Background

Epidemiological studies suggest an association between obesity and asthma in adults and children. Asthma diagnosis criteria are different among studies. The aim of this study was to test the influence of asthma definition on the asthma-obesity relationship.

Methods

In a cross-sectional analysis of 1922 men and women, subjects completed a translated questionnaire from the European Community Respiratory Health Survey and underwent spirometry and a bronchial challenge test. Weight, height and waist circumference were measured. Multiple logistic regression analysis was carried out to assess the association of variables related to obesity and asthma. Asthma was defined either by the presence of symptoms with bronchial hyperresponsiveness (BHR) or by a self-report of a physician-made diagnosis. The following variables were separately tested for associations with asthma: socioeconomic characteristics, schooling, physical activity, smoking status, anthropometry and spirometry.

Results

No association was detected between asthma confirmed by BHR and obesity indicators, odds ratio (OR) = 1.08 (95% confidence interval: 0.69 - 1.68) for obesity assessed by body mass index ≥ 30 kg/m²; OR = 1.02 (0.74 - 1.40) for obesity assessed by abnormal waist-to-height ratio; and, OR = 0.96 (0.69 - 1.33) for abnormal waist circumference. On the contrary, a previous diagnosis of asthma was associated with obesity, OR = 1.48 (1.01 - 2.16) for body mass index ≥ 30 kg/m²; OR = 1.48 (1.13 - 1.93) for abnormal waist-to-height ratio; and, OR = 1.32 (1.00 – 1.75) for abnormal waist circumference. Female gender, schooling ≥ 12 years and smoking were associated with BHR-confirmed asthma. Physically inactive subjects were associated with a previous diagnosis of asthma.

Conclusions

Our findings indicate that the relationship between asthma and obesity in epidemiological studies depends on the definition adopted. Certain components of asthma, for instance, symptoms may be more prone to the obesity influence than other ones, like bronchial hyperresponsiveness.

Comorbid trajectories of tobacco and marijuana use as related to psychological outcomes

Heterogeneous classes of comorbid trajectories of tobacco and marijuana use were examined in order to determine how they are related to subsequent antisocial behavior, poor self-control, and internalizing behavior. Data are from a 4-wave longitudinal study of African American (n = 243) and Puerto Rican (n = 232) adolescents and adults in the community. Logistic regression analyses were employed to measure the association between the comorbid trajectories of tobacco and marijuana use and the psychological difficulty variables. The authors found 6 joint trajectory groups. The authors compared the non-or-experimental tobacco/marijuana use group with the other user groups in each of the psychological difficulty domains. The infrequent tobacco/late-onset marijuana use and chronic tobacco/marijuana use groups differed most strongly from the non-or-experimental tobacco/marijuana use group across the antisocial behavior, poor self-control, and internalizing problems domains. The chronic tobacco/maturing out marijuana use group also had significant associations in each of these domains. The infrequent tobacco/marijuana use and late-onset tobacco/infrequent marijuana use groups had no or weak associations with the psychological outcomes. Tobacco and marijuana cessation programs should identify and address comorbid use of tobacco and marijuana, and antisocial behavior, poor self-control, and internalizing problems, which are associated with histories of comorbid use of the 2 substances.

Large-scale genome-wide association study of Asian population reveals genetic factors in FRMD4A and other loci influencing smoking initiation and nicotine dependence

Diseases related to smoking are the second leading cause of death in the world. Cigarette smoking is a risk factor for several diseases such as cancer and cardiovascular and respiratory disorders. Despite increasing evidence of genetic determination, the susceptibility genes and loci underlying various aspects of smoking behavior are largely unknown. Moreover, almost all reported genome-wide association studies (GWASs) have been performed on samples of European origin, limiting the applicability of the results to other ethnic populations. In this first GWAS on smoking behavior in an Asian population, after analyzing 8,842 DNA samples from the Korea Association Resource project with 352,228 single nucleotide polymorphisms (SNPs) genotyped for each sample, we identified 8 SNPs significantly associated with smoking initiation (SI) and 4 with nicotine dependence (ND). Because of the current unavailability of an independent Asian smoking sample, we replicated the discoveries in independent samples of European-American and African-American origin. Of the 12 SNPs examined in the replicated samples, we identified two SNPs, in the regulator of G-protein signaling 17 gene (rs7747583, p value(meta) = 6.40 × 10(-6); rs2349433, p value(meta) = 5.57 × 10(-6)), associated with SI. Also, we found two SNPs significantly associated with ND; one in the FERM domain containing 4A (rs4424567, p value(meta) = 2.30 × 10(-6)) and the other at 7q31.1 (rs848353, p value(meta) = 9.16 × 10(-8)). These SNPs represent novel targets for examination of smoking behavior and warrant further investigation using independent samples.

Acoustic rhinometry, spirometry and nitric oxide in relation to airway allergy and smoking habits in an adolescent cohort

OBJECTIVE

This study aimed to analyze upper and lower airway function and the impact of smoking habits in a cohort of allergic and healthy adolescents. The influence of smoking habits on the outcomes of rhinitis and asthma is well documented, but only few reports are available showing smoke related upper airway impairment by rhinometric measurements, and none with focus on early changes in adolescents.

METHODS

A cohort followed from infancy was re-examined at the age of 18 years concerning allergy development. Acoustic rhinometry (VOL2), spirometry (FEV(1)) and measurements of nitric oxide levels from the upper (nNO) and lower airways (eNO) were performed before and after physical exercise, and smoking habits were registered.

RESULTS

Active smoking habits were reported by 4/21 subjects suffering from allergic rhinitis, by 1/4 from probable allergic rhinitis, by 0/3 subjects with atopic dermatitis and by 2/10 healthy controls. Smoking habits were reported as daily by 2 and occasional by 5 of the 7 active smokers. VOL2 did not increase in smokers after exercise as in non-smokers, resulting in a post-exercise group difference (7.3±1.1cm(3) vs. 8.8±1.5cm(3); p=0.02), and FEV(1) values were lower in smokers compared to non-smokers (89±7% vs. 98±8%; p=0.02). The nNO and eNO levels were, however, only slightly reduced in smokers. Airway allergy was discerned only in subjects with current allergen exposure by increased eNO levels compared to healthy controls (41±44ppb vs. 13±5ppb). The levels of VOL2, nNO and FEV(1) did not differentiate allergic subjects from healthy controls.

CONCLUSIONS

Low levels of tobacco smoke exposure resulted in reduced airway functions in this adolescent cohort. Acoustic rhinometry and spirometry were found to be more sensitive methods compared to nitric oxide measurements in early detection of airway impairment related to smoke exposure. A possible difference in airway vulnerability between allergic and healthy subjects due to smoke exposure remains to be evaluated in larger study groups.

High frequency of chronic cough and sputum production with lowered exercise capacity in young smokers

OBJECTIVES

The aim was to evaluate how cigarette smoking is associated with respiratory symptoms, fitness, and anthropometric measures in young smokers.

METHODS

The prevalence of smoking was investigated in a cohort of young military draftees (n = 1130; 98% between 18–21 years of age) in Northern Finland. The associations of smoking with respiratory symptoms, physical fitness (12-min running test), education, and anthropometric measures were analysed using a self-reported questionnaire with high response rate (80%).

RESULTS

Almost half (46.5%) of the young males were daily smokers, 17.4% being occasional smokers. The prevalence of self-reported chronic cough and sputum production was high in daily smokers (40.7%) and occasional smokers (26.9%) compared to non-smokers (12%). These symptoms were significantly associated with the smoking history. Aerobic fitness was worse in regular smokers compared to non-smokers (P < 0.001). Smokers had a higher body mass index than non-smokers (P = 0.035). In the regular smokers, the more active the subjects were in sports, the less they smoked when evaluated by pack year history (P < 0.001). Smokers had a lower educational level than occasional smokers or, especially, non-smokers (P < 0.001).

CONCLUSIONS

The frequency of young smokers with chronic cough and sputum production was very high, posing a serious risk to their future health.

The impact of recurrent acute chest syndrome on the lung function of young adults with sickle cell disease

The aim of this study was to assess the impact of recurrent acute chest syndrome (ACS) episodes on the lung function of young adults with sickle cell disease (SCD). Our prospective study included 80 SCD adults [26 with recurrent acute chest syndrome (ACS)] and 80 ethnically matched controls aged between 18 and 28 years. Lung function (spirometry and lung volumes) was measured and the results were expressed as the percentage predicted for height. Bronchial hyperresponsiveness (BHR) was assessed by the response to either a bronchodilator or an exercise challenge. The adults with recurrent ACS (two or more ACS episodes) had lower median forced vital capacity (74 vs. 83%, p = 0.03), forced expiratory volume in 1 s (79 vs. 90%, p < 0.03), and total lung capacity (69 vs. 81%, p = 0.04) than SCD adults who had one or no ACS episodes. The greater the number of ACS episodes, the greater the reduction in lung function (p = 0.001). The adults with SCD had lower median forced vital capacity (81 vs. 106%), forced expiratory volume in 1 s (85 vs. 107%), and total lung capacity (80 vs. 87%) than the controls (p < 0.001). Similar numbers in each group had BHR (p = 0.2). The prevalence of restrictive ventilatory defect in the patients with SCD was almost double that of the controls (p = 0.004). Young adults with SCD have worse lung function than ethnically matched controls, particularly if they have suffered recurrent ACS episodes.

Pharmacogenetics of smoking cessation therapy

Nicotine dependence is a major health problem, with a large amount of smoking-related premature deaths and disabilities. The dependence mechanism of nicotine is especially complex and is under strong genetic influence. Smoking cessation is associated with substantial health benefits. Evidence from animal and human studies suggests that genetic polymorphisms influencing pharmacokinetics and pharmacodynamics of nicotine may have great potential for aiding smoking treatment. There are more than 30 association studies and one genome-wide association study (GWAS) between genetic polymorphisms and smoking cessation following nicotine replacement therapy (NRT) and/or bupropion therapy. However, only a few candidate genes or regions were analyzed more than twice and even these genes require additional investigations in different therapeutic schemes. There are a growing number of new pharmacologic options that have not been pharmacogenetically assessed according to published literature. In addition, molecular genetics studies are needed to assess the functional mechanisms of some putative association results. Taken together, the preliminary findings are promising but raise the need for new studies with adequate sample sizes and adjustment for several potential confounding factors frequently neglected, such as comorbidity and sociodemographic factors. The current state of the art in the field encourages an optimist view that personalized treatment approaches may become possible. However, the current scientific evidence still does not support the use of pharmacogenetic tests in routine smoking cessation therapy.