Smoking status, cigarettes per day, and their relationship to overweight and obesity among former and current smokers in a national adult general population sample

Trends in marijuana and heavy alcohol use by cigarette smoking status among US adults: An analysis of the 2002-2019 NSDUH

BACKGROUND

Polysubstance use is associated with adverse health outcomes, yet little research has measured changes in polysubstance use. We aimed to 1) estimate trends in marijuana and heavy alcohol use by cigarette smoking and demographic subgroups, and 2) examine patient factors associated with concurrent use among adults who were smoking.

METHODS

We conducted a repeated cross-sectional analysis of 687,225 non-institutionalized US adults ≥18 years from the 2002-2019 National Survey on Drug Use and Health. Participants were stratified into current, former, and never smoking groups. Main outcomes were prevalence of heavy alcohol use, marijuana use, and concurrent use of both substances.

RESULTS

From 2002-2019, heavy alcohol use declined from 7.8 % to 6.4 %, marijuana use rose from 6.0 % to 11.8 %, and concurrent use of alcohol and marijuana remained stable. Among adults who were smoking from 2005 to 2019, higher education was associated with higher odds of heavy alcohol use, while older ages, female gender, non-White race/ethnicity, and government-provided health insurance were associated with lower odds. The odds of marijuana use decreased in females, older ages, and higher incomes while increasing in people with poorer health status, higher education, government-provided or no health insurance, and serious mental illness. Compared to White adults who were smoking, Black counterparts had higher odds of marijuana use (OR=1.23; 95 %CI: 1.15-1.29), while Hispanic (OR=0.68; 95 %CI: 0.63-0.72) and other racial/ethnic identities (OR=0.83; 95 %CI: 0.77-0.90) had lower odds.

CONCLUSIONS

Our study suggests marijuana use might not be sensitive to changes in the use of tobacco and alcohol.

Associations between body mass index and smoking behaviour: A cross-sectional study of the German adult population

BACKGROUND

Both smoking and high body weight are risk factors for disease, hence, the association between smoking and body weight is an important health issue. Furthermore, concern about weight gain after quitting smoking is for many smokers a barrier to smoking cessation. The present study aims to explore the association between body mass index (BMI) and current tobacco smoking status in the population of Germany, and smoking and quitting behaviour amongst smokers (and recent ex-smokers =<12 months since quitting).

METHODS

Cross-sectional analysis of two waves of data collected from March through June 2021 through a representative face-to-face household survey in Germany (N = 3 997 respondents aged ≥18). The associations between smoking and quitting behaviours and BMI were analysed through four regression models adjusted for socio-demographic, socio-economic, and smoking characteristics of respondents.

RESULTS

Long-term ex-smokers (>= 12 months since quitting smoking) were more likely to have a higher BMI compared to never smokers (β = 0.64, 95% confidence interval (CI) = 0.10-1.19). There was no statistically significant association between current smoking status or recent ex-smoking status and BMI (β = -0.29,95 %CI = -0.75-0.17 and β = -0.53, 95 %CI = -2.45-1.40). Among current smokers, no statistically significant association was found between BMI and the motivation to stop smoking (OR = 1.01, 95 %CI = 0.99-1.03). Neither number of cigarettes smoked a day nor outcome of most recent quit attempt were related to BMI (β = 0.01, 95 %CI = -0.04-0.05 and OR = 0.41, 95 %CI = 0.05-3.05).

CONCLUSION

In the German population long-term ex-smoking but not current and recent ex-smoking was associated with increased BMI. Future research should further explore the association between smoking behaviour and abdominal obesity, preferably using a more accurate measure for abdominal obesity than BMI.

Effect of a lifestyle intervention to prevent weight gain at initiation of insulin pump therapy in type 2 diabetes: a randomized, controlled, multicentre trial

Insulin pump therapy improves glycaemic control in individuals with type 2 diabetes. However, it may be associated with weight gain.

AIM

To test the effectiveness of a six-month dietary and physical activity intervention, compared to usual care, on weight gain prevention after initiation of insulin pump.

METHODS

Multicentre randomized, controlled trial of 54 individuals. Primary endpoint was between group difference in weight gain at six-months.

RESULTS

Weight gain after 6 months of insulin pump treatment did not differ between groups: mean 3.2 (3.9) kg in the control group and 3.9 (3.8) kg in the intervention group, (p=0.56). HbA1c improved without difference between groups. Post-hoc multivariate analysis of all participants found that weight gain was independently associated with younger age, active smoking, and the magnitude of HbA1c reduction. A 1% decrease in HbA1c was associated with an increase of 0.94kg [95% Confidence Interval 0.47; 1.41], p<0.001.

CONCLUSIONS

Treatment intensification by insulin pump therapy in patients with type 2 diabetes is effective to improve glycaemic control. A gain of about 1 kg per 1% drop in HbA1c can be expected after insulin treatment intensification. This weight gain was not prevented by a home-base, individualized, 6-months lifestyle intervention program.

The pattern of TSH and fT4 levels across different BMI ranges in a large cohort of euthyroid patients with obesity

PURPOSE

A multifold association relates the hypothalamo-pituitary-thyroid axis to body weight. The potential underlying mechanisms are incompletely understood. Further, the mild severity of obesity and the small proportion of individuals with obesity in so far published cohort studies provide little insights on metabolic correlates of thyroid function in obesity.

METHODS

We retrospectively enrolled 5009 adults with obesity (F/M, 3448/1561; age range, 18-87 years; BMI range, 30.0-82.7 kg/m²), without known thyroid disease in a study on TSH and fT4 levels, lipid profile, glucose homeostasis and insulin resistance, anthropometric parameters including BIA-derived fat mass (%FM) and fat-free mass (FFM).

RESULTS

The overall reference interval for TSH in our obese cohort was 0.58-5.07 mIU/L. As subgroups, females and non-smokers showed higher TSH levels as compared to their counterparts (p<0.0001 for both), while fT4 values were comparable between groups. There was a significant upward trend for TSH levels across incremental BMI classes in females, while the opposite trend was seen for fT4 levels in males (p<0.0001 for both). Expectedly, TSH was associated with %FM and FFM (p<0,0001 for both). TSH and fT4 showed correlations with several metabolic variables, and both declined with aging (TSH, p<0.0001; fT4, p<0.01). In a subgroup undergoing leptin measurement, leptin levels were positively associated with TSH levels (p<0.01). At the multivariable regression analysis, in the group as a whole, smoking habit emerged as the main independent predictor of TSH (β=-0.24, p<0.0001) and fT4 (β=-0.25, p<0.0001) levels. In non-smokers, %FM (β=0.08, p<0.0001) and age (β=-0.05, p<0.001) were the main significant predictors of TSH levels. In the subset of nonsmokers having leptin measured, leptin emerged as the strongest predictor of TSH levels (β=0.17, p<0.01).

CONCLUSIONS

Our study provides evidence of a gender- and smoking-dependent regulation of TSH levels in obesity.

Nicotine and energy balance: A review examining the effect of nicotine on hormonal appetite regulation and energy expenditure

Nicotine has been shown to decrease appetite, food intake (FI) and body weight, but the mechanisms are unclear. The purpose of this review was to examine research on the effects of nicotine on energy balance by exploring physiological mechanisms and hormone regulation related to FI, subjective appetite and energy expenditure (EE). We searched PubMed and MEDLINE, and included articles investigating the effects of nicotine on central appetite regulation, FI, leptin, peptide-YY (PYY), ghrelin, glucagon-like peptide-1 (GLP-1), adiponectin, cholecystokinin (CCK), orexin, and EE. A total of 65 studies were included in the qualitative synthesis and review. Our findings suggest that the decrease in appetite and FI may be attributed to nicotinic alterations of neuropeptide Y (NPY) and pro-opiomelanocortin (POMC) but the effect of nicotine on FI remains unclear. Furthermore, nicotine increases resting EE (REE) and physical activity EE (PAEE) in both smokers and non-smokers; and these increases may be a result of the catecholaminergic effect of nicotine. Decreases in body weight and appetite experienced by nicotine users results from increased EE and changes in the central hypothalamic regulation of appetite. There is not enough evidence to implicate a relationship between peripheral hormones and changes in appetite or FI after nicotine use. Although nicotine increases REE and PAEE, the effect of nicotine on other components of EE warrants further research. We conclude that further research evaluating the effect of nicotine on appetite hormones, FI and EE in humans is warranted.

The Intricate Interactions between Maternal Smoking and Drinking During Pregnancy and Birthweight Z-Scores of Preterm Births

BACKGROUND

The extent to which smoking and drinking in a local community is associated with nutrition and Z-scores of infants from spontaneous preterm deliveries, is uncertain.

AIM

To investigate associations of different levels of maternal smoking and drinking in spontaneous preterm birth with infant birthweight Z-scores.

METHODS

Information, including gestational age (determined by earliest ultrasound), maternal arm circumference (measured at enrolment), smoking-drinking data (obtained up to 4 occasions), birthweight data (obtained from medical records) and birthweight Z-scores (calculated from INTERGROWTH- 21st study), collected over a period of nine years was used to compare 407 spontaneous preterm births with 3 493 spontaneous term births Analyses of variance, correlations and multiple regression were performed in STATISTICA.

RESULTS

Women with spontaneous preterm birth, had significantly lower gravidity and smaller arm circumference when compared to women with spontaneous birth at term. Women with spontaneous preterm birth drank more and heavier during pregnancy, and more smoked. Gestational age at birth was significantly longer in heavy-smokers-heavy-drinkers compared to heavy-smokers-no-drinkers (7.1 days) and in no-smokers-heavy-drinkers when compared to no-smokers-no-drinkers (11.2 days). Birthweight was significantly lower in low-smokers-heavy-drinkers when compared to low-smokers-no-drinkers (240g) and in heavy-smokers-low-drinkers when compared to no-smokers-low-drinkers (273g). Birthweight Z-scores were significantly lower in low-smokers-heavy-drinkers when compared to low-smokers-low-drinkers and low-smokers-no-drinkers; and, also significantly lower in heavy-smokers-low-drinkers when compared to low-smokers-low-drinkers and no-smokers-low-drinkers.

CONCLUSION

Alcohol aggravates the detrimental effect of smoking on birthweight and birthweight Z-scores but seems to counteract the negative association of smoking with gestational age.

Metabolic Syndrome and Risk of Lung Cancer: An Analysis of Korean National Health Insurance Corporation Database

INTRODUCTION

Metabolic syndrome is known to increase the risk of several cancers. However, the association between lung cancer and metabolic syndrome remains unclear. Thus, we investigated the impact of metabolic syndrome on the incidence of lung cancer.

METHODS

This study enrolled participants in a health screening program provided by the Korean National Health Insurance Service between January 2009 and December 2012. The incidence of lung cancer was observed until December 2016. We analyzed the risk of lung cancer according to the presence of metabolic syndrome, metabolic syndrome components, and number of metabolic syndrome components.

RESULTS

During the study, 45 635 new cases of lung cancer were recorded among 9 586 753 participants. The presence of metabolic syndrome and all its components was positively associated with the risk of lung cancer in men after multivariate adjustment (hazard ratio [HR] of metabolic syndrome 1.15; 95% confidence interval [CI], 1.12-1.18). The risk of lung cancer increased with the number of components present. The effect of metabolic syndrome on the increasing risk of lung cancer is may be higher in underweight male ever-smokers than in other participants.

CONCLUSION

Metabolic syndrome was associated with an increased risk of lung cancer in men. Moreover, the higher the number of metabolic syndrome components, the higher the risk of lung cancer.

Insights into the association between smoking and obesity: the 2014 Indonesian Family Life Survey

BACKGROUND Various findings on the relationship between smoking and obesity have been demonstrated. This study aimed to investigate the association between smoking behavior and obesity in the Indonesian adult population. METHODS A cross-sectional analysis was conducted using data from the 2014 Indonesian Family Life Survey. A body mass index of ≥25 kg/m² was employed to define obesity. Smoking behavior was assessed in terms of smoking status and its attributes. The potential confounders of gender, age, education, residential environment, economic status, physical activity, and education level were adjusted using logistic regression.  RESULTS Study subjects were 28,949 adults aged ≥20 years. Current smoking was a protective factor of obesity (adjusted odds ratio [aOR] = 0.53; 95% confidence interval [CI] = 0.48–0.58), whereas previous smoking habit showed no association with obesity (aOR = 0.96; 95% CI = 0.84–1.09). The risk of current smokers having obesity was lower than that of nonsmokers as smoking duration increased (aOR = 0.46–0.63). By contrast, the risk of obesity was relatively higher among former smokers than current smokers as the duration of quitting increased (aOR = 1.46–2.20). Heavy smokers had a higher risk of obesity than light smokers among former (aOR = 1.85; 95% CI = 1.27–  2.67) and current smokers (aOR = 1.38; 95% CI = 1.23–1.65). CONCLUSIONS Overall, smoking negatively affected obesity among the Indonesian adult population. By contrast, quitting smoking was associated with an increased risk of obesity. Thus, weight management along with smoking cessation intervention should be prescribed.

Association between post-cessation weight gain and eating behavior changes

OBJECTIVE:

Fear of post-cessation weight gain may be a barrier to cessation therapy or may lead to smoking relapse. This study aimed to evaluate the relationship between the change in eating behavior and post-cessation weight gain.

METHODS:

A prospective study that included 103 cigarette smokers, who visited the family medicine clinics of a training and research hospital for smoking cessation treatment between June 2018 and December 2018, was planned. A face to face survey (including Turkish version of Dutch Eating Behaviour Questionnaire-DEBQ and weight measures) was applied to all individuals at first and the final visits for the assessment of restrained, emotional, and external eating behaviors. Statistical analyses were completed using the IBM SPSS Statistics 22 program.

RESULTS:

Of 103 patients screened (M age=38.3 years SD=9.28), 58.3% were male, and 40.8% were in heavy nicotine dependence level (NDL) group. The mean weight increased by 4.74±2.63 kg in three months of smoking cessation. In the high NDL group, three subscales score (restrained p<0.001, emotional p=0.007, external p=0.005) of the DEBQ increased. Weight gain was significative associated with NDL (p=0.01). There was a positive correlation between Fagerstrom score and weight (kg) gain (r: 0.34; p=0.001). Weight change according to the emotional eating behavior was significantly different by gender (female p=0.005; male p=0.04). Women had a higher difference in emotional eating behavior score than men. Obese smokers had a higher initial restrained eating score than non-obese smokers (p=0.009). Weight gain of nicotine replacement therapy group had a similar result in the pharmacotherapy (varenicline) group (p=0.26). Both of treatment types concluded with a significant weight change (p=0.001).

CONCLUSION:

This study obtained that post-cessation weight gain is related to high nicotine dependence, and quit smoking causes increased scores of emotional, restrained, external eating behavior subscales. Post-cessation eating behavior is negatively affected by quit smoking.

Leisure-Time Physical Inactivity’s Association With Environmental, Demographic, and Lifestyle Factors in the United States

Background: This study examined the effects of environmental, demographic, and lifestyle factors on leisure-time physical inactivity (LTPI). Methods: Analyses were based on county-level data in the contiguous United States. Statistical methods included simple regression, univariate, and multivariate 2-level organizational models (mixed models), and the intraclass correlation coefficient. Results: Higher average daily maximum air temperature was directly and indirectly (through smoking and obesity) positively associated with LTPI. Higher average fine particulate matter was positively associated with LTPI. Higher precipitation was negatively associated with LTPI. Altitude (≥1500 m) was associated with lower LTPI, directly because of better physical health at higher altitude and indirectly through temperature, fine particulate matter, precipitation, poverty, smoking, and obesity. Urban dwelling had direct and indirect (through poverty) negative associations with LTPI. Poverty had direct and indirect (through smoking and obesity) associations with LTPI. Smoking, poverty, and black race were each positively associated with LTPI. The association between black race and LTPI was explained by poverty. Modifying influences of gender, precipitation, and altitude were identified. Conclusions: The significant effects of temperature, fine particulate matter, precipitation, altitude, urban dwelling, poverty, smoking, and obesity on LTPI were both direct and indirect, and sex, precipitation, and altitude modified many of these associations.

Interactions of Behavioral Changes in Smoking, High-risk Drinking, and Weight Gain in a Population of 7.2 Million in Korea

OBJECTIVES

To identify simultaneous behavioral changes in alcohol consumption, smoking, and weight using a fixed-effect model and to characterize their associations with disease status.

METHODS

This study included 7 000 529 individuals who participated in the national biennial health-screening program every 2 years from 2009 to 2016 and were aged 40 or more. We reconstructed the data into an individual-level panel dataset with 4 waves. We used a fixed-effect model for smoking, heavy alcohol drinking, and overweight. The independent variables were sex, age, lifestyle factors, insurance contribution, employment status, and disease status.

RESULTS

Becoming a high-risk drinker and losing weight were associated with initiation or resumption of smoking. Initiation or resumption of smoking and weight gain were associated with non-high-risk drinkers becoming high-risk drinkers. Smoking cessation and becoming a high-risk drinker were associated with normal-weight participants becoming overweight. Participants with newly acquired diabetes mellitus, ischemic heart disease, stroke, and cancer tended to stop smoking, discontinue high-risk drinking, and return to a normal weight.

CONCLUSIONS

These results obtained using a large-scale population-based database documented interactions among lifestyle factors over time.

Factors Associated with High Weight Gain and Obesity Duration: The Norwegian Women and Cancer (NOWAC) Study

AIM

To identify factors associated with high weight gain and obesity duration in a representative sample of Norwegian women.

METHODS

66,618 Norwegian women aged 34-70 years at baseline were included in the analysis. Baseline and follow-up questionnaires completed in 1991-2011 provided information on height, weight as well as sociodemographic, lifestyle and reproductive factors. We assessed the association with multivariable logistic regression.

RESULTS

Women gained on average 0.5 kg/year (95% CI 0.5-0.5 kg/year) during 6 years of follow-up, and 3.5% maintained in obesity during 13 years of follow-up. The factors with strongest association with high weight gain (≥10 kg) were smoking cessation (cessation vs. no change, OR = 4.39, 95% CI 3.91-4.94) and decreased physical activity level (decrease vs. no change, OR = 2.40, 95% CI 2.21-2.61). Low physical activity level (high vs. low, OR = 0.17, 95% CI 0.14-0.20), higher than median age at menarche (over median vs. median or under median, OR = 0.36, 95% CI 0.31-0.41), and less than 10 years of education (>12 years vs. <10 years, OR = 0.44, 95% CI 0.37-0.51) were strongly associated with obesity duration.

CONCLUSION

The modifiable factor with the strongest association with adverse weight development and potential for prevention was low or decreased physical activity level.

Continuous outcome logistic regression for analyzing body mass index distributions

Body mass indices (BMIs) are applied to monitor weight status and associated health risks in populations.  Binary or multinomial logistic regression models are commonly applied in this context, but are only applicable to BMI values categorized within a small set of defined ad hoc BMI categories.  This approach precludes comparisons with studies and models based on different categories.  In addition, ad hoc categorization of BMI values prevents the estimation and analysis of the underlying continuous BMI distribution and leads to information loss.  As an alternative to multinomial regression following ad hoc categorization, we propose a continuous outcome logistic regression model for the estimation of a continuous BMI distribution.  Parameters of interest, such as odds ratios for specific categories, can be extracted from this model post hoc in a general way.  A continuous BMI logistic regression that describes BMI distributions avoids the necessity of ad hoc and post hoc category choice and simplifies between-study comparisons and pooling of studies for joint analyses.  The method was evaluated empirically using data from the Swiss Health Survey.

Contextual influences affecting patterns of overweight and obesity among university students: a 50 universities population-based study in China

Background

Many studies have examined childhood and adolescent obesity, but few have examined young adults and the effect of their home and current living environments on prevalence rates. The present study explores contextual factors affecting overweight and obesity among university students in China and, in particular, focuses on how the SES–obesity relationship varies across different geographical contexts.

Methods

Participants were 11,673 students, who were identified through a multistage survey sampling process conducted in 50 universities. Individual data was obtained through a self-administered questionnaire, and contextual variables were retrieved from a national database. Multilevel logistic regression models were used to examine urban and regional variations in overweight and obesity.

Results

Overall the prevalence of overweight and obesity in the study sample was 9.5% (95% CI 7.7, 11.3%). After controlling for individual factors, both attributes of the home location (regional GDP <gross domestic product> per capita and rurality) and the current university location (city population) were found to be important, thus suggesting that the different origins of students affect current levels of obesity. At the individual level, while students with more financial resources were more likely to be obese, the extent of this relationship was highly dependent upon area income and city size.

Conclusion

The results of this study add important insights about the role of contextual factors affecting overweight and obesity among young adults and indicate a need to take into account both past as well as present environmental influences when considering the role of contextual factors in models of the nutrition transition.

Changes in Obesity Odds Ratio among Iranian Adults, since 2000: Quadratic Inference Functions Method

Background. Monitoring changes in obesity prevalence by risk factors is relevant to public health programs that focus on reducing or preventing obesity. The purpose of this paper was to study trends in obesity odds ratios (ORs) for individuals aged 20 years and older in Iran by using a new statistical methodology. Methods. Data collected by the National Surveys in Iran, from 2000 through 2011. Since responses of the member of each cluster are correlated, the quadratic inference functions (QIF) method was used to model the relationship between the odds of obesity and risk factors. Results. During the study period, the prevalence rate of obesity increased from 12% to 22%. By using QIF method and a model selection criterion for performing stepwise regression analysis, we found that while obesity prevalence generally increased in both sexes, all ages, all employment, residence, and smoking levels, it seems to have changes in obesity ORs since 2000. Conclusions. Because obesity is one of the main risk factors for many diseases, awareness of the differences by factors allows development of targets for prevention and early intervention.

Association between Smoking Status and Obesity in a Nationwide Survey of Japanese Adults

OBJECTIVE

A positive association between the number of cigarettes smoked per day and obesity has been reported, whereas how other smoking-related indices, such as pack-years and duration of smoking, are related with obesity has been less investigated. We analyzed the age-adjusted cross-sectional association between smoking and obesity in a general Japanese population.

METHODS

We used data from a nationwide epidemiological study of Japanese adults (N = 23,106). We compared the prevalence of obesity (defined as body mass index ≥ 25kg/m2) among groups classified by smoking behavior, pack-years, number of cigarettes per day, duration of smoking, and duration and time of smoking cessation.

RESULTS

In men, current smokers had a lower odds ratio (OR) for obesity of 0.80 (95% confidence interval (CI): 0.72-0.88) compared to non-smokers, whereas past smokers had a higher OR of 1.23 (95% CI: 1.09-1.37) compared to current smokers. In women, there were no differences in obesity between the three groups classified by smoking behavior. However, in both sexes, the prevalence of obesity tended to increase with pack-years and the number of cigarettes per day, but not with duration of smoking in current and past smokers. Further, in male smokers, the risks for obesity were markedly higher in short-term heavy smokers compared with long-term light smokers, even with the same number of pack-years. Regarding the impact of smoking cessation, female past smokers who quit smoking at an age > 55-years had an elevated OR of 1.60 (95% CI:1.05-2.38) for obesity.

CONCLUSIONS

In a general Japanese population, obesity is progressively associated with pack-years and number of cigarettes per day, but not with the duration of smoking. When investigating the association between obesity and cigarette smoking, the daily smoking burden and the duration of smoking require to be independently considered.

Back on track-Smoking cessation and weight changes over 9 years in a community-based cohort study

OBJECTIVE

To examine the impact of smoking cessation on body weight compared with normal long-term weight development.

METHODS

Of 1970 adults (20-69 years) in a rural town in Denmark invited to take part in the study in 1998-2000, 1374 (70%) participated. After 9 years, 1121 participated in the follow-up study. Weight changes were compared using multivariable regression models.

RESULTS

The mean baseline weight of never-smokers was 76.4 kg (SD 16.0). The adjusted weight of smokers and ex-smokers differed by -4.2 kg (95% CI: -5.9, -2.6), and -0.7 kg (95% CI: -2.5, 1.1), respectively. The adjusted weight gain rate (kg/year) of never-smokers, smokers, and ex-smokers was 0.213, 0.127, and 0.105, respectively. The absolute post cessation weight gain (PCWG) was 5.0 kg (SD 7.0), and the adjusted PCWG was 2.8 kg (95% CI: 1.7, 3.9) compared with never-smokers, and 3.5 kg (95% CI: 2.3, 4.8) compared with smokers. The follow-up weight did not differ between quitters and never-smokers (0.1 kg; 95% CI: -2.4, 2.6).

CONCLUSION

Smokers weigh less than never-smokers. By quitting, they gain weight and end up weighing the same as comparable never-smokers. Weight gain rates differ by smoking status. Consequently, PCWG depends on the length of follow-up. Our graphical model indicates that smoking cessation results in a return to normal weight development.

Association between body composition and khat chewing in Ethiopian adults

BACKGROUND

Khat (Catha edulis Forsk) is a psychostimulant herb widely cultivated and used in Ethiopia. The link between khat use and body composition is little known.

OBJECTIVE

The aim was to determine the association between body composition and khat use.

METHODS

We recruited 415 individuals 18-78 years of age from Jimma Town. Sociodemographic and lifestyle data were collected using structured questionnaires. Fat mass (FM, kg) and fat-free mass (FFM, kg) were estimated from whole-body bio impedance. Weight (kg), FM and FFM were indexed to height (m) as BMI (kg/m(2)), fat mass index (FMI) (kg/m) and fat-free mass index (FFMI) (kg/m), respectively. Independent predictors of BMI, FMI and FFMI were identified using regression analysis.

RESULT

Participants' mean ± SD of age was 37 ± 13 years and 205 (53.2 %) were males. Mean ± SD of BMI, FMI and FFMI were 21.0 kg/m(2) ± 4.1, 6.8 kg/m ± 5.2 and 27.9 kg/m ± 3.8, respectively. Multivariable model showed that, compared with non-chewers, khat chewers had a lower BMI (B = -1.56, 95 % CI -0.78, -2.33) and FMI (B = 2.19, 95 % CI -1.32, -3.06). FMI was lower in cigarette smokers than non-smokers by -1.36 kg/m (95 % CI -0.23, -2.49). Concurrently, khat and cigarette users increased FMI by 2.78 (95 % CI 0.11, 5.44). FFMI decreased with age (B = -0.02, 95 % CI -0.05, -0.002).

CONCLUSION

FMI and BMI were lower in khat users than non-users, but there was no difference in lean mass. The consequence of this body composition change should be investigated.

Association between Smoking Status and Food and Nutrient Consumption in Japanese: a Large-Scale Cross-Sectional Study

BACKGROUND

In Japan, in comparison with the rest of the world the death rate of lung cancer is low although the smoking rate is relatively high. This is the so-called "Japanese smoking paradox". A healthy diet is proposed to attenuate the risk without quitting smoking. We here examined the relationships between smoking status (SS) and the consumption of food and nutrient in Japan.

MATERIALS AND METHODS

Totals of 5,587 men and 2,718 women were divided into three (non-smokers, smokers and heavy smokers) and two (non-smokers and smokers) groups, respectively, according to pack-year, which represents the amount of smoking over a long period. Food and nutrient consumption was estimated with a validated food frequency questionnaire. Using general linear models, food and nutrient consumption was estimated for each group in men and women, separately.

RESULTS

In men, SS was positively related to consumption of rice, 3 alcoholic beverages, carbohydrate, alcohol and other 8 foods/nutrients (p<0.05 for all) and negatively to those of protein animal, fat, fatty acids, dietary fiber, isoflavones and 36 other foods/nutrients (p<0.05 for all). In women, SS was positively associated with intake of 13 foods/nutrients, while being negatively associated with those of rice, energy, dietary fiber, and 14 other foods/nutrients (p<0.05 for all).

CONCLUSIONS

Our results support lower intake of vegetables and fruits rich in antioxidants, which are thought as preventive factors for many diseases, in smokers.

Gender differences influence overweight smokers' experimentation with electronic nicotine delivery systems

INTRODUCTION

Overweight and obese tobacco users possess increased risk of cancer, diabetes, heart disease and chronic tobacco-related disease. Efforts to prevent tobacco-related health risk in this comorbid population would be informed by better understanding and monitoring of trends in the concurrent use of electronic nicotine delivery systems (ENDS) among smokers in the US marketplace.

METHOD

The California Longitudinal Smokers Study (CLSS) established a cohort of current cigarette smokers in 2011 who were surveyed for tobacco use and health behavior at baseline and again in 2012 at follow-up.

RESULTS

We observed a large increase in reported experimentation with ENDS. As hypothesized, overweight or obese smokers were more likely to report experimentation with ENDS, an increase that was also observed among women. Experimentation with ENDS was not associated with a reduction in use of cigarettes or a decrease in cigarette dependence in this high risk population of smokers.

CONCLUSIONS

Continued surveillance of this vulnerable population is needed to better understand how experimentation with new ENDS products may impact health, facilitate switching to non-combustible tobacco or facilitate persistent cigarette dependence.

Inpatient smoking cessation therapy: truth or dare?

BACKGROUND

This study aims to answer the question to which extent even very heavy nicotine-dependent smokers can benefit from a 3-week inpatient smoking cessation program. A particular focus lies on analyzing the positive effects, which go above and beyond normally anticipated health benefits.

METHODS

This is a descriptive study observing 270 patients over a 1-year period consisting of recruitment, therapy, and two post-therapy follow-up visits at 6-month interval. Gender differences, changes in body weight, and factors relating to addiction and the nicotine withdrawal process are analyzed. In comparing successful participants-post-therapy nonsmokers-with less successful ones, our analysis identifies benefits and advantages an inpatient smoking cessation therapy can bring to even the heaviest smokers.

RESULTS

At the 12-month post-therapy follow-up visit, 42.6% of participants were identified as nonsmokers. A total of 34.0% of participants took up smoking again. No data is available on the remaining participants. Nonsmokers experienced significant reduction in nicotine craving and withdrawal symptoms. In terms of body weight, increases were found in both, men and women, nonsmokers and smokers.

CONCLUSION

Successful quitters fail to report of an unbearable strong desire to smoke. Such unfounded fear should be communicated. Weight gain remains an undesired side effect. Hence, it is crucial to diagnose individuals more prone to weight gain and offer coping strategies thus reducing the risk of developing obesity. Nevertheless, the outcome of the study should be an encouragement to also heavy smokers and empower them to undertake smoking cessation.

Obesity and Related Factors in Iran: The STEPS Survey, 2011

Background:

To date, no study has addressed the association between race/ethnicity and obesity considering other sociodemographic and lifestyle factors in Iran.

Objectives:

The current study aimed to study lifestyle and the environmental factors affecting obesity in the Iranian subjects of the STEPS Survey, 2011.

Patients and Methods:

The study was conducted on 8639 subjects (aged ≥ 20 years) in the STEPS Survey 2011 in Iran under supervision of the World Health Organization (WHO). Height and body weight were measured following the standardized procedures. Generalized Estimating Equations (GEE) method was used to examine factors associated with obesity. The examined variables were age, gender, race/ethnicity, place of residence, employment status, physical activity, smoking status, and educational level.

Results:

Overall, 22.3% of the subjects were obese. In a GEE model, a healthy weight status among adults was associated with being younger, male, in a rural residence, employees, spending more time engaged in physical activity, being a smoker and having a moderate or high level of education. These associations were statistically significant after adjusting for other variables.

Conclusions:

The study results suggest a need for targeted interventions and continued surveillance for the Iranian adults.

Anthropometry and head and neck cancer:a pooled analysis of cohort data

BACKGROUND

Associations between anthropometry and head and neck cancer (HNC) risk are inconsistent. We aimed to evaluate these associations while minimizing biases found in previous studies.

METHODS

We pooled data from 1,941,300 participants, including 3760 cases, in 20 cohort studies and used multivariable-adjusted Cox proportional hazard regression models to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association of anthropometric measures with HNC risk overall and stratified by smoking status.

RESULTS

Greater waist circumference (per 5 cm: HR = 1.04, 95% CI 1.03-1.05, P-value for trend = <0.0001) and waist-to-hip ratio (per 0.1 unit: HR = 1.07, 95% CI 1.05-1.09, P-value for trend = <0.0001), adjusted for body mass index (BMI), were associated with higher risk and did not vary by smoking status (P-value for heterogeneity = 0.85 and 0.44, respectively). Associations with BMI (P-value for interaction = <0.0001) varied by smoking status. Larger BMI was associated with higher HNC risk in never smokers (per 5 kg/m(2): HR = 1.15, 95% CI 1.06-1.24, P-value for trend = 0.0006), but not in former smokers (per 5 kg/m(2): HR = 0.99, 95% CI 0.93-1.06, P-value for trend = 0.79) or current smokers (per 5 kg/m(2): HR = 0.76, 95% CI 0.71-0.82, P-value for trend = <0.0001). Larger hip circumference was not associated with a higher HNC risk. Greater height (per 5 cm) was associated with higher risk of HNC in never and former smokers, but not in current smokers.

CONCLUSIONS

Waist circumference and waist-to-hip ratio were associated positively with HNC risk regardless of smoking status, whereas a positive association with BMI was only found in never smokers.

The mediating effect of body mass index on the relationship between cigarette smoking and atopic sensitization in Chinese adults

BACKGROUND

It is unclear whether the relationship between cigarette smoking and atopy is mediated by body fat mass, such as the Body Mass Index (BMI). We assessed the mediating role of BMI on the relationship between smoking and atopy in Chinese adults.

METHODS

A hospital-based case-control study of 786 atopic cases and 2771 controls was conducted in adults aged 18 years or older from March 2010 to September 2014 in Harbin, China. Mediation models were used to estimate the indirect effects of smoking on atopic sensitization through BMI.

RESULTS

Compared to non-smokers, light smokers and moderate smokers had a lower risk of inhalant allergen sensitization. The indirect effect of smoking and sensitization to aeroallergens were only observed in light smokers (point estimate, -0.026; 95% CI, -0.062 to -0.004). The mediating roles of BMI on the relationships between smoking and other types of allergic sensitization were not statistically significant.

CONCLUSION

BMI appeared to partially mediate the effect of light smoking on sensitization to aeroallergens. However, considering the other harmful health effects of cigarette smoking, the effective method to lower the incidence of atopy would be to decrease body fat mass by physical exercise and employing other more healthy ways of living rather than smoking.

High tobacco consumption lowers body weight: a Mendelian randomization study of the Copenhagen General Population Study

BACKGROUND

Conflicting evidence has been found regarding the association between high tobacco consumption and body weight among smokers. We tested the hypothesis that high tobacco consumption is causally associated with low body weight.

METHODS

We conducted a Mendelian randomization study with a genetic variant in CHRNA3 (rs1051730) as proxy for high tobacco consumption. The cohort consisted of 80,342 participants from the Copenhagen General Population Study, with details on body weight, smoking habits and CHRNA3 genotype, including 15,220 current smokers.

RESULTS

In observational analyses, high tobacco consumption was associated with high body weight, body mass index, waist circumference, hip circumference and waist-hip ratio. In multivariable adjusted models a 1-cigarette/day higher tobacco consumption was associated with 0.05 kg (95% confidence interval 0.02; 0.08) higher body weight, 0.02 kg/m(2) (0.01; 0.02) higher body mass index, 0.10 cm (0.07; 0.12) higher waist circumference and 0.02 cm (0.001; 0.03) higher hip circumference. In contrast, the per-allele increase inCHRNA3 rs1051730 associated with high tobacco consumption was associated with 0.59 kg (0.96; 0.22) lower body weight, 0.23 kg/m(2) (0.33; 0.13) lower body mass index, 0.32 cm (0.74; 0.003) lower waist circumference and 0.45 cm (0.66; 0.24) lower hip circumference. No association was found between tobacco consumption and waist-hip ratio in genetic analysis, or among CHRNA3 genotype and any of the outcome variables in former or never smokers.

CONCLUSIONS

High tobacco consumption causes lower body weight among current smokers. However, smoking does not seem to affect body shape or fat distribution causally. The lack of association between CHRNA3 genotype and body weight among former smokers and never smokers favours smoking as the causal factor for the observed associations.

Weight control belief and its impact on the effectiveness of tobacco control policies on quit attempts: findings from the ITC 4 Country Survey

BACKGROUND

Weight concerns are widely documented as one of the major barriers for girls and young adult women to quit smoking. Therefore, it is important to investigate whether smokers who have weight concerns respond to tobacco control policies differently than smokers who do not in terms of quit attempts, and how this difference varies by gender and country.

OBJECTIVE

This study aims to investigate, by gender and country, whether smokers who believe that smoking helps control weight are less responsive to tobacco control policies with regards to quit attempts than those who do not.

METHODS

We use longitudinal data from the International Tobacco Control Policy Evaluation Project in the USA, Canada, the UK and Australia to conduct the analysis. We first constructed a dichotomous indicator for smokers who have the weight control belief and then examined the disparity in policy responsiveness in terms of quit attempts by directly estimating the interaction terms of policies and the weight control belief indicator using generalised estimating equations.

FINDINGS

We find that weight control belief significantly attenuates the policy impact of tobacco control measures on quit attempts among US female smokers and among UK smokers. This pattern was not found among smokers in Canada and Australia.

CONCLUSIONS

Although our results vary by gender and country, the findings suggest that weight concerns do alter policy responsiveness in quit attempts in certain populations. Policy makers should take this into account and alleviate weight concerns to enhance the effectiveness of existing tobacco control policies on promoting quitting smoking.

Ceramides mediate cigarette smoke-induced metabolic disruption in mice

Cigarette smoke exposure increases lung ceramide biosynthesis and alters metabolic function. We hypothesized that ceramides are released from the lung during cigarette smoke exposure and result in elevated skeletal muscle ceramide levels, resulting in insulin resistance and altered mitochondrial respiration. Employing cell and animal models, we explored the effect of cigarette smoke on muscle cell insulin signaling and mitochondrial respiration. Muscle cells were treated with conditioned medium from cigarette smoke extract (CSE)-exposed lung cells, followed by analysis of ceramides and assessment of insulin signaling and mitochondrial function. Mice were exposed to daily cigarette smoke and a high-fat, high-sugar (HFHS) diet with myriocin injections to inhibit ceramide synthesis. Comparisons were conducted between these mice and control animals on standard diets in the absence of smoke exposure and myriocin injections. Muscle cells treated with CSE-exposed conditioned medium were completely unresponsive to insulin stimulation, and mitochondrial respiration was severely blunted. These effects were mitigated when lung cells were treated with the ceramide inhibitor myriocin prior to and during CSE exposure. In mice, daily cigarette smoke exposure and HFHS diet resulted in insulin resistance, which correlated with elevated ceramides. Although myriocin injection was protective against insulin resistance with either smoke or HFHS, it was insufficient to prevent insulin resistance with combined CS and HFHS. However, myriocin injection restored muscle mitochondrial respiration in all treatments. Ceramide inhibition prevents metabolic disruption in muscle cells with smoke exposure and may explain whole body insulin resistance and mitochondrial dysfunction in vivo.

Smoking and weight among patients using clozapine

BACKGROUND

Both obesity and smoking are common in schizophrenia patients taking clozapine, causing cardiovascular disease and premature deaths.

METHODS

Two hundred and thirty-seven patients with schizophrenia or related psychoses treated with clozapine completed the Liverpool University Neuroleptic Assessment Scale (LUNSERS) and a questionnaire including current height, weight, changes therein and smoking status.

AIMS

The aim of this study was to analyze weight and weight change in smoking and non-smoking patients taking clozapine. A possible interaction between obesity and smoking was explored.

RESULTS

No association was found between weight change and smoking status during clozapine treatment. There was no significant difference in body mass index (BMI) between non-smokers and smokers. In the analysis of covariance (ANCOVA) with BMI as the dependent variable, the best fitting model comprised age, sex, intensity of sedation, and reported amount of smoking as explanatory variables (ηp(2)= 0.116; P = 0.029; power = 0.750). None of the explanatory proportions of any single factor was significant.

CONCLUSIONS

Estimated according to reported weight gain and BMI, no difference was found between smoking and non-smoking clozapine-treated patients. Number of cigarettes smoked explained BMI if age and sex were taken into account. This result is in line with the findings of some general population studies, where heavy smoking has been associated with a greater risk of obesity.

Examining substance use and affective processes as multivariate risk factors associated with overweight body mass among treatment-seeking smokers

Cigarette smoking and obesity are two major public health problems. However, factors related to the underlying risk for being overweight are not well established. Certain demographic, smoking, and psychological factors have been linked to overweight/obese body mass. The current study examined a multivariate risk model, stratified by gender, in order to better explicate the nature of overweight body mass among daily smokers. In a sample of treatment-seeking smokers (n = 395), among males and females, (1) older age, (2) stronger expectancies about the weight/appetite control effects of smoking, (3) greater smoking-based inflexibility/avoidance due to smoking-related sensations, and (4) less problematic alcohol use, were associated with being overweight. Additionally, among males, having a tobacco-related medical problem and higher tolerance for physical discomfort aided in the discriminant function model for classifying smokers as overweight. Together, numerous cognitive-affective vulnerabilities and smoking processes may be targetable and potentially inform weight-related prevention programs among smokers.

The association of smoking and demographic characteristics on body mass index and obesity among adults in the U.S., 1999-2012

BACKGROUND

The National Health and Nutrition Examination Surveys (NHANES) are an exceptional data source for studies of smoking and body weight because they are the only federal survey series collecting relevant information through detailed interviews and medical examinations. The associations of smoking status and demographic factors with body weight have not been evaluated fully in recent NHANES.

METHODS

Using NHANES datasets from 1999 to 2012, this study uses ordinary-least squares and ordered probit models to investigate the association of smoking and selected demographic variables with body mass index (BMI) and the probability of being in BMI categories among adults aged 25-64 years, and it uses quantile regression to examine whether these factors affect individuals differently depending on where they are located across the BMI distribution.

RESULTS

The sample consisted of 11,123 men and 10,949 women. Current smokers had significantly lower BMI than never smokers (1.97 unit for men and 1.46 unit for women), and there was modest variation across the BMI distribution. Among former smokers, only women had a slightly higher BMI compared to never smokers (0.46 unit). Both men and women current smokers were more likely to be underweight and normal weight compared to never smokers and were less likely to be obese. Among men a one-year age increase elevated BMI by 0.2 unit throughout the BMI distribution, while for women an extra year of age increased BMI at the upper tail of the distribution more than at the lower tail. Education beyond high school was associated with a significant decrease in BMI among women, but much less so among men. Married men had higher BMI, but married women had significantly lower BMI, and this difference became larger at the upper tail.

CONCLUSIONS

Compared to never smokers, men and women current smokers had lower BMI and lower probability of obesity, while only women former smokers had elevated BMIs and increased probability of obesity. In addition, we found that age, education and marital status were associated with different effects on BMI in men and women.

The relationship between waterpipe smoking and body weight: population-based findings from Syria

INTRODUCTION

Cigarette smoking has well known effects on body weight, with current smokers weighing less than never-smokers, and cessation producing weight gain. Use of waterpipe (or "hookah") is increasing in many parts of the world but its effects on body weight are not known.

METHODS

We compared body mass index (BMI) among 2,536 adults (age ≥ 18 years old), who were never, former, current nondaily, or current daily waterpipe smokers, drawn from 2 representative, population-based household surveys of adults in Aleppo, Syria.

RESULTS

Overall, 84.1% (n = 2,134) never-smoked waterpipe, 4.6% (n = 116) were former smokers, 9.9% (n = 251) were current nondaily smokers, and 1.4% (n = 35) were current daily smokers. Mean BMI of the sample was 30.2 kg/m(2) (SD = 6.3). Adjusted for cigarette smoking, number of chronic diseases, age, gender, income, and marital status, daily waterpipe users were 2.26 BMI units greater than never-smokers (beta = 2.26, 95% CI = 0.79-3.72), and had nearly threefold odds of being obese (odds ratio = 2.87, 95% CI = 1.06-7.76). Nondaily and former waterpipe users were similar to never-smokers in terms of BMI and obesity risk.

CONCLUSION

Results indicate that daily waterpipe users, compared to never-users, have higher BMI, translating into 6 extra kilograms of weight on average, and are 3 times as likely to be obese.

Joint association of nicotinic acetylcholine receptor variants with abdominal obesity in American Indians: the Strong Heart Family Study

Cigarette smoke is a strong risk factor for obesity and cardiovascular disease. The effect of genetic variants involved in nicotine metabolism on obesity or body composition has not been well studied. Though many genetic variants have previously been associated with adiposity or body fat distribution, a single variant usually confers a minimal individual risk. The goal of this study is to evaluate the joint association of multiple variants involved in cigarette smoke or nicotine dependence with obesity-related phenotypes in American Indians. To achieve this goal, we genotyped 61 tagSNPs in seven genes encoding nicotine acetylcholine receptors (nAChRs) in 3,665 American Indians participating in the Strong Heart Family Study. Single SNP association with obesity-related traits was tested using family-based association, adjusting for traditional risk factors including smoking. Joint association of all SNPs in the seven nAChRs genes were examined by gene-family analysis based on weighted truncated product method (TPM). Multiple testing was controlled by false discovery rate (FDR). Results demonstrate that multiple SNPs showed weak individual association with one or more measures of obesity, but none survived correction for multiple testing. However, gene-family analysis revealed significant associations with waist circumference (p = 0.0001) and waist-to-hip ratio (p = 0.0001), but not body mass index (p = 0.20) and percent body fat (p = 0.29), indicating that genetic variants are jointly associated with abdominal, but not general, obesity among American Indians. The observed combined genetic effect is independent of cigarette smoking per se. In conclusion, multiple variants in the nAChR gene family are jointly associated with abdominal obesity in American Indians, independent of general obesity and cigarette smoking per se.

Familial aggregation of tobacco use behaviors among Amish men

INTRODUCTION

Tobacco use is a complex behavior. The Old Order Amish community offers unique advantages for the study of tobacco use because of homogenous ancestral background, sociocultural similarity, sex-specific social norms regarding tobacco use, and large family size. Tobacco use in the Old Order Amish community is almost exclusively confined to males.

METHODS

We examined characteristics of tobacco use and familial aggregation among 1,216 Amish males from cross-sectional prospectively collected data. Outcomes examined included ever using tobacco regularly, current use, quantity of use, duration of use, and frequency of use.

RESULTS

Sixteen percent of Amish men were current tobacco users, with the majority reporting cigar use only. Higher rates of tobacco use were found among sons of fathers who smoked compared with sons of fathers who did not smoke (46% vs. 22%, p < .001) as well as among brothers of index cases who smoked compared with brothers of index cases who did not smoke (61% vs. 29%, p < .001). After controlling for shared household effects and age, heritability accounted for 66% of the variance in ever smoking regularly (p = .045).

CONCLUSIONS

The familial patterns of tobacco use observed among Amish men highlight the important role of family in propagating tobacco use and support the usefulness of this population for future genetic studies of nicotine addiction.

Association between a serum thyroid-stimulating hormone concentration within the normal range and indices of obesity in Japanese men and women

OBJECTIVE

This cross-sectional study investigated the associations between the serum thyroid-stimulating hormone (TSH) concentration and indices of obesity in middle-aged Japanese men and women.

METHODS

The participants were 2,037 employees (1,044 men and 993 women; age, 36-55 yr) of a metal products factory in Japan. Clinical examinations were conducted in 2009. We obtained a medical history and anthropometric measurements (body weight, body mass index [BMI] and waist circumference) and measured the serum TSH concentrations. The anthropometric indices were compared across serum TSH quartiles. The associations were evaluated separately according to the smoking status in men.

RESULTS

The mean body weight (kg), BMI (kg/m(2)) and waist circumference (cm) were 69.2, 23.7 and 83.2 in men and 55.3, 22.3 and 74.3 in women, respectively. Men with a higher TSH concentration had higher body weight and BMI values (p for trend=0.016 and 0.019, respectively), and these significant associations were observed even after adjusting for age, smoking status and other potential confounders. The TSH level was not associated with waist circumference. We found a significant interaction between the TSH level and the smoking status on body weight (p for interaction=0.013) and a significant association between the TSH level and body weight in nonsmokers, but not in current smokers. No significant associations were observed between the TSH level and the anthropometric indices in women.

CONCLUSION

Significant positive associations between the serum TSH concentration, body weight and BMI were detected in men only, and an interaction with the smoking status was observed for this association.

Cigarette smoking and the risk of Barrett's esophagus: a systematic review and meta-analysis

BACKGROUND AND AIM

Barrett's esophagus (BE) is a premalignant condition to esophageal adenocarcinoma. It is currently not clear whether cigarette smoking increases the risk of developing BE, and no meta-analysis has been performed on the topic. We conducted a systematic review and meta-analysis, providing a quantitative estimate of the increased risk of BE associated with cigarette smoking, to help clarify whether a relationship exists between smoking and BE.

METHODS

Four electronic databases (Medline, PubMed, Embase, and Current Contents Connect) were searched to May 17, 2013, for observational studies of BE patients. We calculated pooled odds ratios (ORs) and 95% confidence intervals (CIs) using a random effects model for the association of smoking with BE. BE patients were compared with non-gastroesophageal reflux disease (GERD) controls as well as with population-based and GERD controls.

RESULTS

Thirty-nine studies comprising 7069 BE patients were included in the meta-analysis. Having ever-smoked was associated with an increased risk of BE compared with non-GERD controls (OR 1.44; 95% CI 1.20-1.74), population-based controls (OR 1.42; 95% CI 1.15-1.76), but not GERD controls (OR 1.18; 95% CI 0.75-1.86). The meta-analyses of the studies reporting the lowest and highest number of pack-years smoked showed an increased risk of BE (OR 1.41; 95% CI 1.22-1.63) and (OR 1.53; 95% CI 1.27-1.84), respectively.

CONCLUSION

Cigarette smoking was associated with an increased risk of BE. Being an ever-smoker was associated with an increased risk of BE in all control groups. A greater number of pack-years smoked was associated with a greater risk of BE.

Obesity and endocrine dysfunction programmed by maternal smoking in pregnancy and lactation

Obesity is a global epidemic, and maternal smoking has been shown to be associated with the development of childhood obesity. Overall, approximately 40% of children worldwide are exposed to tobacco smoke at home. It is well known that environmental changes within a critical window of development, such as gestation or lactation, can initiate permanent alterations in metabolism that lead to diseases in adulthood, a phenomenon called programming. It is known that programming is based on epigenetic alterations (changes in DNA methylation, histone acetylation, or small interfering RNA expression) that change the expression pattern of several genes. However, little is known concerning the mechanisms by which smoke exposure in neonatal life programs the adipose tissue and endocrine function. Here, we review several epidemiological and experimental studies that confirm the association between maternal nicotine or tobacco exposure during gestation or lactation and the development of obesity and endocrine dysfunction. For example, a positive correlation was demonstrated in rodents between increased serum leptin in the neonatal period and exposure of the mothers to nicotine during lactation, and the further development of leptin and insulin resistance, and thyroid and adrenal dysfunction, in adulthood in the same offspring. Thus, a smoke-free environment during the lactation period is essential to improving health outcomes in adulthood and reducing the risk for future diseases. An understanding of the pathophysiological mechanisms underlying the effects of smoking on programming can provide new insights into therapeutic strategies for obesity.

The effect of stability and change in health behaviors on trajectories of body mass index in older Americans: a 14-year longitudinal study

BACKGROUND

Obesity is increasingly prevalent among older adults, yet little is known about the impact of health behaviors on the trajectories of body weight in this age group.

METHODS

We examined the effect of time-varying smoking, physical activity (PA), alcohol use, and changes thereof, on the 14-year (1992-2006) trajectory of body- mass index (BMI) in a cohort of 10,314 older adults from the Health and Retirements Study, aged 51-61 years at baseline. Hierarchical linear modeling (HLM) quantifies the effect of smoking, PA, and alcohol use (user status, initiation and cessation) on intercept and rate-of-change in BMI trajectory, and tests for variations in the strength of association between each behavior and BMI.

RESULTS

Over 14 years (82,512 observations), BMI increased approximated by a quadratic function. Smoking and PA (user status and initiation) were associated with significantly lower BMI trajectories over time. Cessation of smoking and PA resulted in higher BMI trajectories over time. The weight-gaining effect of smoking cessation increased, while the strength of association between BMI trajectories and PA or alcohol use were constant over time. Socio-economic and health status differences explained the effects of alcohol use on BMI trajectory.

CONCLUSIONS

In older adults, smoking and PA, and changes thereof, vary in their long-term effect on trajectories of BMI. Barring increases in PA levels, older smokers who quit today are expected to gain significantly more weight than two decades ago. This knowledge is essential for the design of smoking cessation, physical activityPA, and weight-control interventions in older adults.

[Overweight: socio-demographic and behavioral determinants in Brazilian adults, 2008]

This article aims to identify socio-demographic and behavioral determinants of overweight among Brazilian adults living in State capitals and the Federal District, using data collected by a telephone survey for surveillance of risk and protective factors in 2008. The outcome variable was overweight, and the independent variables were socio-demographics, behavioral factors, and nutritional status at 20 years of age. The overweight rate was 44.4%. Socio-demographic factors associated with overweight were age and marital status (married) in both genders, higher schooling in men, and lower schooling in women. With the exception of overweight at 20 years of age, behavioral factors were associated differently with overweight according to gender (leisure-time physical inactivity in males and dietary patterns and watching television among females). The behavioral determinants of overweight differed between men and women, thus indicating the need for diverse gender-specific strategies.

Disparities in the prevalence of obesity in Boston: results from the Boston Area Community Health (BACH) survey

OBJECTIVE

This study examined disparities in the prevalence of obesity to determine how future prevention and/or intervention efforts should be developed to remedy obesity.

METHODS

We obtained individual information of sociodemographic characteristics, comorbid conditions, and lifestyle behaviors from the Boston Area Community Health (BACH) survey for 2002-2005. To account for the complex BACH sampling design, observations were weighted inversely to their probability of selection, and sampling weights were poststratified to the Boston population from the U.S. Census 2000. We tested all possible two- and three-way interaction terms from a multivariate logistic regression model.

RESULTS

After controlling for individual determinants in detail and focusing on the population within a single city, the associations of sociodemographic characteristics, comorbid conditions, and lifestyle behaviors with obesity were consistent with previous findings. Notably, three two-way interaction terms were significantly associated with obesity: (1) race/ethnicity and gender, (2) gender and other people in the household, and (3) race/ethnicity and alcohol consumption.

CONCLUSIONS

Future obesity prevention and/or intervention programs in Boston need to be primarily gender- and racially/ethnically specific to minimize cost and maximize results. Additional considerations are needed to take into account the differences in age, the presence of other people in the household, and education level.

Thyroid hormone levels predict the change in body weight: a prospective study

BACKGROUND

Different studies, mostly cross-sectional, have found an association between low levels of thyroid hormones, even within the normal range, and a greater body mass index. The aim of this study was to determine the association between thyroid function and the risk for obesity.

MATERIALS AND METHODS

In this population-based prospective study, measurements were made of anthropometric parameters, thyroid hormone function and urinary iodine in a cohort of the Pizarra Study (n = 937), and repeated 6 years later (n = 784). At the second point, measurements were also made of leptin and adiponectin.

RESULTS

Among the persons who were not obese at the start of the study, the odds ratio (OR) of becoming obese for those in the fourth quartile (Q(4)) for free triiodothyronine (FT3) (versus those in Q(1)) was 2·94 (1·46-5·90) (P = 0·005). The OR of becoming obese in persons in Q(4) of FT4 (versus those in Q(1)) was 3·06 (1·23-7·43) (P = 0·01). Those persons in Q(4) of weight gain had a higher FT3 at the 6-year follow-up than those whose weight gain was in Q(1) (P < 0·001). Leptin correlated with thyrotropin (β = 0·58, P = 0·001) and the FT4 (β = -1·12, P = 0·005). Adiponectin correlated with FT3 (r = -0·24, P < 0·001). The urinary iodine correlated negatively with both the BMI (β = -0·08, P = 0·01) and the increase in weight (β = -0·08, P = 0·04).

CONCLUSIONS

The changes in the thyroid hormones could be the consequence, rather than the cause, of the increase in weight. The same pathophysiological mechanisms that induce obesity might also be modifying the thyroid hormone pattern.

The tobacco industry's past role in weight control related to smoking

Background: Smoking is thought to produce an appetite-suppressing effect by many smokers. Thus, the fear of body weight gain often outweighs the perception of health benefits associated with smoking cessation, particularly in adolescents. We examined whether the tobacco industry played a role in appetite and body weight control related to smoking and smoking cessation. Methods: We performed a systematic search within the archives of six major US and UK tobacco companies (American Tobacco, Philip Morris, RJ Reynolds, Lorillard, Brown & Williamson and British American Tobacco) that were Defendants in tobacco litigation settled in 1998. Findings are dated from 1949 to 1999. Results: The documents revealed the strategies planned and used by the industry to enhance effects of smoking on weight and appetite, mostly by chemical modifications of cigarettes contents. Appetite-suppressant molecules, such as tartaric acid and 2-acetylpyridine were added to some cigarettes. Conclusion: These tobacco companies played an active and not disclaimed role in the anti-appetite effects of smoking, at least in the past, by adding appetite-suppressant molecules into their cigarettes.

The association between change in body mass index and upper aerodigestive tract cancers in the ARCAGE project: multicenter case-control study

Previous studies reported an inverse relationship between body mass index (BMI) and upper aerodigestive tract (UADT) cancers. Examining change in BMI over time may clarify these previous observations. We used data from 2,048 cases and 2,173 hospital- and population-based controls from ten European countries (alcohol-related cancers and genetic susceptibility in Europe study) to investigate the relationship with BMI and adult change in BMI on UADT cancer risk. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated for associations between BMI at three time intervals and BMI change on UADT cancer development, adjusting for center, age, sex, education, fruit and vegetable intake, smoking and alcohol consumption. We found an inverse relationship between UADT cancers and BMI at time of interview and 2 years before interview. No association was found with BMI at 30 years of age. Regarding BMI change between age 30 and 2 years before interview, BMI decrease (BMI change <-5%) vs. BMI stability (-5% ≤ BMI change <5%) showed no overall association with UADT cancers (OR = 1.15; 95% CI = 0.89, 1.49). An increase in BMI (BMI change ≥+5%) was inversely associated with UADT cancers (OR = 0.74; 95% CI = 0.62, 0.89). BMI gain remained inversely associated across all subsites except for esophageal cancer. When stratified by smoking or by drinking, association with BMI gain was detected only in drinkers and smokers. In conclusion, BMI gain is inversely associated with UADT cancers. These findings may be influenced by smoking and/or drinking behaviors and/or the development of preclinical UADT cancers and should be corroborated in studies of a prospective nature.

Dose-dependent positive association between cigarette smoking, abdominal obesity and body fat: cross-sectional data from a population-based survey

Background

Although smokers tend to have a lower body-mass index than non-smokers, smoking may favour abdominal body fat accumulation. To our knowledge, no population-based studies have assessed the relationship between smoking and body fat composition. We assessed the association between cigarette smoking and waist circumference, body fat, and body-mass index.

Methods

Height, weight, and waist circumference were measured among 6,123 Caucasians (ages 35-75) from a cross-sectional population-based study in Switzerland. Abdominal obesity was defined as waist circumference ≥102 cm for men and ≥88 cm for women. Body fat (percent total body weight) was measured by electrical bioimpedance. Age- and sex-specific body fat cut-offs were used to define excess body fat. Cigarettes smoked per day were assessed by self-administered questionnaire. Age-adjusted means and odds ratios were calculated using linear and logistic regression.

Results

Current smokers (29% of men and 24% of women) had lower mean waist circumference, body fat percentage, and body-mass index compared with non-smokers. Age-adjusted mean waist circumference and body fat increased with cigarettes smoked per day among smokers. The association between cigarettes smoked per day and body-mass index was non-significant. Compared with light smokers, the adjusted odds ratio (OR) for abdominal obesity in men was 1.28 (0.78-2.10) for moderate smokers and 1.94 (1.15-3.27) for heavy smokers (P = 0.03 for trend), and 1.07 (0.72-1.58) and 2.15 (1.26-3.64) in female moderate and heavy smokers, respectively (P < 0.01 for trend). Compared with light smokers, the OR for excess body fat in men was 1.05 (95% CI: 0.58-1.92) for moderate smokers and 1.15 (0.60-2.20) for heavy smokers (P = 0.75 for trend) and 1.34 (0.89-2.00) and 2.11 (1.25-3.57), respectively in women (P = 0.07 for trend).

Conclusion

Among smokers, cigarettes smoked per day were positively associated with central fat accumulation, particularly in women.

Photoelectric stimulation of defined ear points (Smokex-Pro method) as an aid for smoking cessation: a prospective observational 2-year study with 156 smokers in a primary care setting

BACKGROUND

Smokex-Pro is a smoking cessation method using a protocol of a standardized consultation and computer-assisted photoelectric stimulation of defined regions in the ear and face.

METHODS

We prospectively enrolled 156 consecutive adult smokers (81 males, 75 females; mean age 43.8 years; body mass index 25.5; daily cigarettes 24.7; Fagerström Test for Nicotine Dependence 5; 30 smoking years). The primary end point was the self-reported continuous abstinence rate.

RESULTS

Participants completed on average only 32% of recommended visits. A total of 76.7% stopped smoking for more than 7 days. Moreover, 53.4% remained free of smoking for more than 90 days. Long-term abstinence rates were 49.3% (1 year) and 47.95% (2 years). Treatment-related side effects were observed in 24.5% of participants. Side effects were mild and resolved within hours.

CONCLUSION

The Smokex-Pro method appears to be an effective aid for smoking cessation. The treatment was well tolerated and showed only mild and temporary side effects. The average cost of treatment is typically less than EUR 90; the total treatment time is typically 60-90 min. These factors make it an attractive alternative compared to traditional smoking cessation methods. Controlled clinical trials will be needed to confirm the results of this study and refine the treatment for maximum efficacy.

Free triiodothyronine is associated with smoking habit, independently of obesity, body fat distribution, insulin, and metabolic parameters

BACKGROUND

The aim of this study was to examine the relationship between thyroid hormones and smoking and several other parameters like age, gender, insulin, and anthropometric and metabolic parameters in subjects with a wide range of body mass index (BMI).

PATIENTS AND METHODS

A total of 931 euthyroid normal weight (BMI<25.0 kg/m2), overweight and obese subjects (BMI ≥25.0 kg/m2), 663 women and 268 men, aged 18-68 yr, were investigated. Fasting TSH, free T3 (FT3), free T4 (FT4), insulin, glucose, and lipid serum levels were determined. Waist circumference was measured as an indirect parameter of central fat accumulation.

RESULTS

Smokers were younger (p<0.001) and showed higher FT3 (p<0.01), and triglyceride (p<0.01) levels and lower glucose (p<0.01) and HDL (p<0.001) concentrations than non smoking subjects. FT3 levels were directly associated with BMI (p<0.001), waist circumference (p<0.001), insulin (p<0.001), and triglyceride (p<0.01) levels and negatively correlated with age (p<0.001) and HDL-cholesterol levels (p<0.001). When a multiple regression analysis was performed with FT3 levels as the dependent variable, and smoking, age, gender, and TSH, insulin, triglyceride, and HDL-cholesterol serum concentrations as independent variables, FT3 levels maintained an independent positive association with smoking (p<0.05), age (p<0.001), male sex (p<0.001), waist circumference (p<0.05), and insulin levels (p<0.001).

CONCLUSIONS

Smoking increases FT3 levels independently of age, gender, obesity, body fat distribution and metabolic parameters.