Metabolic effects of smoking cessation

Acute nicotine activates orectic and inhibits anorectic brain regions in rats exposed to chronic nicotine

Nicotine use produces psychoactive effects, and chronic use is associated with physiological and psychological symptoms of addiction. However, chronic nicotine use is known to decrease food intake and body weight gain, suggesting that nicotine also affects central metabolic and appetite regulation. We recently showed that acute nicotine self-administration in nicotine-dependent animals produces a short-term increase in food intake, contrary to its long-term decrease of feeding behavior. As feeding behavior is regulated by complex neural signaling mechanisms, this study aimed to test the hypothesis that nicotine intake in animals exposed to chronic nicotine may increase activation of pro-feeding regions and decrease activation of pro-satiety regions to produce the acute increase in feeding behavior. FOS immunohistochemistry revealed that acute nicotine intake in nicotine self-administering animals increased activation of the pro-feeding arcuate and lateral hypothalamic nuclei and decreased activation of the pro-satiety parabrachial nucleus. Regional correlational analysis also showed that acute nicotine changes the functional connectivity of the hunger/satiety network. Further dissection of the role of the arcuate nucleus using electrophysiology found that putative POMC neurons in animals given chronic nicotine exhibited decreased firing following acute nicotine application. These brain-wide central signaling changes may contribute to the acute increase in feeding behavior we see in rats after acute nicotine and provide new areas of focus for studying both nicotine addiction and metabolic regulation.

Targeting GLP-1 receptors to reduce nicotine use disorder: Preclinical and clinical evidence

Nicotine use disorder (NUD) remains a leading cause of preventable death in the U.S. Unfortunately, current FDA-approved pharmacotherapies for smoking cessation have limited efficacy and are associated with high rates of relapse. One major barrier to long-term smoking abstinence is body weight gain during withdrawal. Nicotine withdrawal-induced body weight gain can also lead to development of chronic disease states like obesity and type II diabetes mellitus. Therefore, it is critical to identify novel pharmacotherapies for NUD that decrease relapse and nicotine withdrawal symptoms including body weight gain. Recent studies demonstrate that glucagon-like peptide-1 receptor (GLP-1R) agonists attenuate voluntary nicotine taking and seeking and prevent withdrawal-induced hyperphagia and body weight gain. Emerging evidence also suggests that GLP-1R agonists improve cognitive deficits, as well as depressive- and anxiety-like behaviors, which contribute to smoking relapse during withdrawal. While further studies are necessary to fully characterize the effects of GLP-1R agonists on NUD and understand the mechanisms by which GLP-1R agonists decrease nicotine withdrawal-mediated behaviors, the current literature supports GLP-1R-based approaches to treating NUD.

Substance use and incidence of metabolic syndrome before midlife among military adults: the CHIEF cohort study

Backgrounds

Habitual substance use, i. e., alcohol, tobacco and betel nut, has been found with an increased risk of metabolic syndrome (MetS) in the general population, whereas the association remains unclear in physically fit military personnel. This study aimed to investigate the combination of these substances use and their associations with new-onset MetS in the military.

Methods

A total of 2,890 military men and women, aged 18-39 years, without MetS were obtained from the cardiorespiratory fitness and health in eastern armed forces study (CHIEF) in Taiwan and followed for incident MetS from baseline (2014) through the end of 2020. Incident MetS event was defined by the International Diabetes Federation guideline and confirmed in the annual health examinations. A self-report was used to assess the alcohol, tobacco and betel nut use status (active vs. former/never). Multivariable Cox regression model was performed to determine the association with adjustments for sex, age, body mass index and physical activity at baseline.

Results

At baseline, there were 279 active betel nut chewers (9.7%), 991 active smokers (34.3%) and 1,159 active alcohol consumers (40.1%). During a mean follow-up of 6.0 years, 673 incident MetS (23.3%) were observed. As compared to no substance users, only one substance, and two and three substances users had a greater risk of incident MetS [hazard ratios (HRs) and 95% confidence intervals: 1.27 (1.06-1.54), 1.38 (1.12-1.69) and 1.78 (1.37-2.32), respectively]. In subgroup analyses, the risk of incident MetS in two and three substances users was significantly greater in those free of baseline low high-density lipoprotein [HRs: 1.54 (1.21-1.95) and 2.57 (1.92-3.46), respectively], as compared to their counterparts (both p for interactions <0.05).

Conclusion

A dose-response association of more substances use for new-onset MetS was noted in military personnel. This finding suggests that the combined alcohol, tobacco and betel nut use may play a role in the development of MetS. Further study is required to establish causation and to investigate the potential benefits of substance use cessation in reducing the risk of MetS.

When smoke meets gut: deciphering the interactions between tobacco smoking and gut microbiota in disease development

Tobacco smoking is a prevalent and detrimental habit practiced worldwide, increasing the risk of various diseases, including chronic obstructive pulmonary disease (COPD), cardiovascular disease, liver disease, and cancer. Although previous research has explored the detrimental health effects of tobacco smoking, recent studies suggest that gut microbiota dysbiosis may play a critical role in these outcomes. Numerous tobacco smoke components, such as nicotine, are found in the gastrointestinal tract and interact with gut microbiota, leading to lasting impacts on host health and diseases. This review delves into the ways tobacco smoking and its various constituents influence gut microbiota composition and functionality. We also summarize recent advancements in understanding how tobacco smoking-induced gut microbiota dysbiosis affects host health. Furthermore, this review introduces a novel perspective on how changes in gut microbiota following smoking cessation may contribute to withdrawal syndrome and the degree of health improvements in smokers.

Utilization of the microbiome in personalized medicine

Inter-individual human variability, driven by various genetic and environmental factors, complicates the ability to develop effective population-based early disease detection, treatment and prognostic assessment. The microbiome, consisting of diverse microorganism communities including viruses, bacteria, fungi and eukaryotes colonizing human body surfaces, has recently been identified as a contributor to inter-individual variation, through its person-specific signatures. As such, the microbiome may modulate disease manifestations, even among individuals with similar genetic disease susceptibility risks. Information stored within microbiomes may therefore enable early detection and prognostic assessment of disease in at-risk populations, whereas microbiome modulation may constitute an effective and safe treatment tailored to the individual. In this Review, we explore recent advances in the application of microbiome data in precision medicine across a growing number of human diseases. We also discuss the challenges, limitations and prospects of analysing microbiome data for personalized patient care.

Effects of Electronic Nicotine Delivery Systems Substitution on Body Weight Status: Protocol for a Systematic Review and Meta-Analysis

BACKGROUND

Weight gain following smoking cessation is a well-documented concern, often attributed to the absence of nicotine's metabolic influence. The adoption of Electronic Nicotine Delivery Systems (ENDS) has been used to achieve smoking cessation, with claims of aiding weight control. However, existing reviews present conflicting conclusions on ENDS' impact on weight status, necessitating a rigorous evaluation.

OBJECTIVE

We aim to conduct a systematic review with meta-analysis to assess the actual impact of ENDS on weight status in individuals who have ceased or reduced conventional smoking. The primary goal is to provide clinicians with evidence-based insights into the potential effects of ENDS use as a smoking substitute on weight control.

METHODS

Adhering to PRISMA-P (Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols) guidelines, our systematic review will analyze randomized and nonrandomized controlled trials, clinical trials (quasi-experimental), and prospective or retrospective cohort studies on the weight status effects of ENDS among individuals who have either quit or reduced smoking. Searches will include PubMed, Scopus, and Cochrane Library, covering the period from 2010 to January 2024. A gray literature search and supplementary searches will be performed. Data will be extracted independently by 2 reviewers and quality assessments will be conducted concurrently. Quality assessments will use Joanna Briggs Institute tools, 2020 version, along with bias assessments for internal validity and reporting bias based on the Catalogue of Bias. The included studies will be examined for any internal data reporting discrepancies by using Puljak's checklist. Meta-analysis and subgroup analyses (ie, general ENDS usage, ENDS use coupled with a reduction in smoking exceeding 50%, and exclusive ENDS use for achieving smoking cessation) are planned. Certainty of evidence will be evaluated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework.

RESULTS

The protocol has been registered in PROSPERO (CRD42023494974) and the entire systematic review is expected to be completed by April 2024. The main goal of this review is to retrieve all current human research studies investigating the influence of ENDS on weight management among individuals who have quit or reduced smoking. Furthermore, the review will assess the quality of these studies and examine potential biases to identify the most dependable evidence available. Dissemination strategies will include traditional journal publications, social media announcements, and a white paper. The latter, available for download and distributed at conferences, aims to reach a broad audience, including clinicians and ENDS users.

CONCLUSIONS

The review will address the importance of informing health care professionals and patients about the current and robust evidence regarding the effects of transitioning to ENDS for smoking cessation on weight status.

TRIAL REGISTRATION

PROSPERO CRD42023494974; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=494974.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/56324.

The Association between Smoking Exposure and Reflux Esophagitis: A Cross-sectional Study among Men Conducted as a Part of Health Screening

Objective Gastroesophageal reflux disease (GERD), including reflux esophagitis (RE), is recognized as a common gastrointestinal disease, and its prevalence is reported to be increasing. While current cigarette smoking has been established as a risk factor for RE in several cross-sectional studies, most of these studies did not include details concerning the smoking status in their analyses. Smoking-related conditions, such as chronic lung disease and cough, are reportedly also related to GERD. Methods To investigate the association between RE and detailed smoking habits, we performed a cross-sectional analysis of healthy men enrolled in a comprehensive health checkup program conducted in 2015 that included esophago-gastro-duodenoscopy. Smoking status was assessed using a self-reported questionnaire. Other smoking-related parameters, including the lung function, cough symptoms and presence of chronic lung disease, were also assessed. Unconditional logistic regression was applied to calculate the odds ratio (OR) with 95% confidence intervals (CIs) after adjusting for confounding factors. Results The study included 151 subjects with RE (RE group) and 814 without RE (control group). Compared with never-smokers, former smokers (OR, 1.5; 95% CI, 0.9-2.9) and current smokers (OR, 2.4; 95% CI, 1.5-3.9) showed an increased risk of RE. An increased risk of RE was also observed among subjects with current smoking for 10-20 PYs and more than 20 PYs (OR, 2.8; 95% CI, 1.4-5.8, OR, 3.1; 95% CI, 1.6-5.7 respectively). An elevated risk was observed in former smokers who reported more than 20 PYs (OR, 2.5; 95% CI, 1.3-4.8). When former smokers were stratified according to time since smoking cessation, a significant RE risk was observed in participants who had stopped smoking less than 10 years earlier compared with never smokers (OR, 1.9; 95% CI, 1.1-3.3). No significant associations were observed between chronic cough, FEV1.0%, and RE. Conclusion Cumulative lifetime exposure to smoking plays an important role in the risk of RE.

Development and Evaluation of a Health Behavior Change Clinic in Primary Care: An Interdisciplinary Partnership

Providing effective healthy behavior change interventions within primary care presents numerous challenges. Obesity, tobacco use, and sedentary lifestyle negatively impact the health quality of numerous medical patients, particularly in underserved patient populations with limited resources. Primary Care Behavioral Health (PCBH) models, which incorporate a Behavioral Health Consultant (BHC), can offer point-of-contact psychological consultation, treatment, and also provide opportunities for interdisciplinary psychologist-physician clinical partnerships to pair a BHC's health behavior change expertise with the physician's medical care. Such models can also enhance medical training programs by providing resident physicians with live, case-based learning opportunities when partnered with a BHC to address patient health behaviors. We will describe the development, implementation, and preliminary outcomes of a PCBH psychologist-physician interdisciplinary health behavior change clinic within a Family Medicine residency program. Patient outcomes revealed significant reductions (p < .01) in weight, BMI, and tobacco use. Implications and future directions are discussed.

Association between anti-smoking campaign types and smoking cessation attempts

Objective

This study explored the association between anti-smoking campaign types and smoking cessation attempts.

Methods

This study included 4,594 individuals (3,292 male and 1,302 female) from the Korea Youth Risk Behavior Web-based Survey (KYRBWS) in 2018 and 2020. The methods of anti-smoking promotion were divided into online, offline, online and offline, and none. Attempts to quit smoking were classified as yes or no. Multiple logistic regression was performed to examine the association between antismoking campaign type and smoking cessation attempts.

Results

Those who saw anti-smoking advertisements both online and offline were found to have tried to quit smoking more than those who did not. (Online & offline: male, odds ratio [OR] 1.36; 95% confidence interval [95% CI], 1.08-1.71; female, OR, 1.75; 95% CI 1.21-2.54) In a subgroup analysis of the independent variables into which smoking cessation advertisements were subdivided, males were found to have the highest OR for smoking cessation attempts when they encountered advertisements in newspapers. (Newspaper: male, OR, 2.25; 95% CI, 1.00-5.02) Females had the highest OR for smoking cessation attempts when accessed via the Internet. (Internet: female, OR, 1.93; 95% CI, 1.07-3.50).

Conclusion

This study showed that there is a correlation between smoking cessation advertisements and adolescents' smoking cessation attempts. The possibility of smoking cessation attempts is high when encountering smoking cessation advertisements both online and offline. Although offline smoking cessation advertisements have a great effect on adolescents' smoking cessation attempts, it can be confirmed that the frequency of exposure for offline advertisements is less than that for online advertisements.

Relationship of constipation, body mass index increase and cigarette craving with nutrition in the smoking cessation process: A cross-sectional study from Turkey

This cross-sectional study was conducted to determine the complaints of constipation, increase in body mass index (BMI) and cigarette craving levels and their relationship with nutrition at the end of the 1st month following quit smoking. Individuals who applied to a Smoking Cessation Clinic in Izmir, Turkey were included in the study (N = 87, mean age 44.13 ± 12.67 years). Frequent constipation in daily life and greater than 30 g fat consumption increased constipation complaints, whereas increasing the number of cigarettes smoked before quitting decreased constipation complaints. BMI increase was higher in those who experienced severe constipation after quitting smoking. Cigarette cravings increased as the educational level of the participants increased. Individuals who were obese before quitting had lower levels of cigarette craving. During the smoking cessation process, it will be useful to question the situation of constipation in daily life. Studies examining types of fat and fatty acids should be planned.

Adverse physiological effects of smoking cessation on the gastrointestinal tract: A review

Smoking cessation is known to have numerous health benefits, but it can also induce adverse physiological effects, including those affecting the gastrointestinal tract (GIT). Understanding the adverse physiological effects of smoking cessation on the GIT is critical for healthcare professionals and smokers attempting to quit, as it enables them to anticipate and manage potential challenges during the smoking cessation process. Although the detrimental effects of smoking on the GIT have been well established, there is a gap in the literature regarding the specific physiological reactions that may occur upon smoking cessation. This mini-review summarizes the current literature on the predisposing factors, pathophysiology, clinical presentation, and treatment options for adverse physiological effects of smoking cessation on the GIT. We aimed to raise awareness among busy clinical professionals about these adverse effects, empowering them to effectively support individuals striving to quit smoking and maintain their cessation. By consolidating the existing knowledge in this field, this review offers practical implications for smokers, healthcare providers, and policymakers to optimize smoking cessation interventions and support strategies to improve health outcomes.

Effect of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol and benzo[a]pyrene exposure on the development of metabolic syndrome in mice

AIM

The prevalence of metabolic syndrome (MetS), a cluster of serious medical conditions that raise the risk of lung cancer, has increased worldwide. Tobacco smoking (TS) potentially increases the risk of developing MetS. Despite the potential association of MetS with lung cancer, preclinical models that mimic human diseases, including TS-induced MetS, are limited. Here we evaluated the impact of exposure to tobacco smoke condensate (TSC) and two representative tobacco carcinogens, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNK) and benzo[a]pyrene (BaP), on MetS development in mice.

MATERIALS AND METHODS

FVB/N or C57BL/6 mice were exposed to vehicle, TSC, or NNK and BaP (NB) twice weekly for 5 months. The serum levels of total cholesterol (TCHO), triglycerides, high-density lipoprotein (HDL), blood glucose, and metabolites, along with glucose tolerance and body weight, were measured.

KEY FINDINGS

Compared with those of vehicle-treated mice, mice with TSC or NB exposure displayed major phenotypes associated with MetS, including increased serum levels of TCHO, triglycerides, and fasting and basal blood glucose and decreased glucose tolerance, and serum levels of HDL. These MetS-associated changes were found in both FVB/N and C57BL/6 mice that were susceptible or resistant to carcinogen-induced tumorigenesis, respectively, indicating that tumor formation is not involved in the TSC- or NB-mediated MetS. Moreover, oleic acid and palmitoleic acid, which are known to be associated with MetS, were significantly upregulated in the serum of TSC- or NB-treated mice compared with those in vehicle-treated mice.

SIGNIFICANCE

Both TSC and NB caused detrimental health problems, leading to the development of MetS in experimental mice.

The absence of association between anorexia nervosa and smoking: converging evidence across two studies

Previous studies have found increased smoking prevalence amongst adults with anorexia nervosa (AN) compared to the general population. The current investigation explored bidirectional associations between AN and smoking behaviour (initiation and heaviness), to address questions surrounding causation. In Study One, logistic regression models with variance robust standard errors assessed longitudinal associations between AN and smoking, using data from adolescent participants of the Avon Longitudinal Study of Parents and Children (N = 5100). In Study Two, two-sample Mendelian randomisation (MR) tested possible causal effects using summary statistics from publicly available genome-wide association studies (GWAS). Study One provided no clear evidence for a predictive effect of AN on subsequent smoking behaviour, or for smoking heaviness/initiation predicting later AN. MR findings did not support causal effects between AN and smoking behaviour, in either direction. Findings do not support predictive or causal effects between AN and smoking behaviour. Previously reported associations may have been vulnerable to confounding, highlighting the possibility of smoking and AN sharing causal risk factors.

Association of post-smoking cessation changes in fasting serum glucose with changes in predicted fatty liver score

Major post-cessation metabolic changes include weight gain and hyperglycemia. However, the association of post-cessation change in fasting serum glucose (FSG) with risk of fatty liver remains unclear. A total of 111,106 participants aged 40 and above who underwent health screening at least once in two examination periods were extracted from the Korean National Health Insurance Service-National Sample Cohort. Fatty liver status was evaluated using the Korean National Health and Nutrition Examination Survey nonalcoholic fatty liver disease (K-NAFLD) score. Linear and logistic regression were used to calculate the adjusted mean (aMean) and adjusted odds ratio (aOR) with 95% confidence intervals. Compared to stable (aMean 0.10; 95% CI 0.03-0.18) and decline (aMean - 0.60; 95% CI - 0.71 to 0.49) groups, FSG elevation (aMean 1.28; 95% CI 1.16-1.39) was associated with higher K-NAFLD score even within different body mass index change groups. Risk of fatty liver was significantly reduced among participants with stable (aOR 0.38; 95% CI 0.31-0.45) and declined (aOR 0.17; 95% CI 0.13-0.22) FSG levels after smoking cessation compared to FSG elevation group. This study suggests that quitters with elevated FSG are associated with higher NAFLD risk and may benefit from careful monitoring of FSG levels and management of other cardiovascular risk factors.

Continuous glucose monitoring in a healthy population: understanding the post-prandial glycemic response in individuals without diabetes mellitus

Continuous glucose monitoring has become a common adjunct in the management of Diabetes Mellitus. However, there has been a recent trend among individuals without diabetes using these devices as a means of monitoring their health. The increased visibility of glucose data has allowed users to study the effect lifestyle has upon post-prandial glucose levels. Although post-prandial hyperglycemia is well understood in the setting of diabetes, its impact in individuals without diabetes is less well defined. This article reviews the factors which contribute to post-prandial hyperglycemia in individuals without diabetes and how the data obtained from continuous glucose monitoring can be used to improve an individual's metabolic health.

Obesity and Abdominal Obesity in Indian Population: Findings from a Nationally Representative Study of 698,286 Participants

This study aims to determine and compare the prevalence and correlates of obesity and abdominal obesity in India among participants aged 18-54 years. Data were acquired from the nationally representative National Family Health Survey 2019-21. Age and sex standardized descriptive analyses were conducted to determine the prevalence of obesity and abdominal obesity, and multivariable multilevel logistic regression was performed to identify the factors associated with these conditions. Gender-specific analyses were also conducted. The sample weight was adjusted throughout. The final sample size for this study was 698,286. The prevalence of obesity and abdominal obesity was 13.85% and 57.71%, respectively. Older age, being female, increased educational status and increased wealth index, being married at any point, and residing in an urban area all increased the odds of both obesity and abdominal obesity. Being a resident of the North zone and having a current alcohol intake increased the odds of abdominal obesity. On the other hand, being a resident of the South zone of India increased the odds of obesity. Targeting these high-risk groups can be a strategy for public health promotion programs.

Glucagon-like peptide-1 analogues: a new way to quit smoking? (SKIP)-a structured summary of a study protocol for a randomized controlled study

BACKGROUND

Cigarette smoking is the leading preventable cause of premature death. Despite dedicated programmes, quit rates remain low due to barriers such as nicotine withdrawal syndrome or post-cessation weight gain. Glucagon-like peptide-1 (GLP-1) analogues reduce energy intake and body weight and seem to modulate addictive behaviour. These GLP-1 properties are of major interest in the context of smoking cessation. The aim of this study is to evaluate the GLP-1 analogue dulaglutide as a new therapy for smoking cessation.

METHODS

This is a placebo-controlled, double-blind, parallel group, superiority, single-centre randomized study including 255 patients. The intervention consists of a 12-week dulaglutide treatment phase with 1.5 mg once weekly or placebo subcutaneously, in addition to standard of care (behavioural counselling and pharmacotherapy with varenicline). A 40-week non-treatment phase follows. The primary outcome is the point prevalence abstinence rate at week 12. Smoking status is self-reported and biochemically confirmed by end-expiratory exhaled carbon monoxide measurement. Further endpoints include post-cessational weight gain, nicotine craving analysis, glucose homeostasis and long-term nicotine abstinence. Two separate substudies assess behavioural, functional and structural changes by functional magnetic resonance imaging and measures of energy metabolism (i.e. resting energy expenditure, body composition).

DISCUSSION

Combining behavioural counselling and medical therapy, e.g. with varenicline, improves abstinence rates and is considered the standard of care. We expect a further increase in quit rates by adding a second component of medical therapy and assume a dual effect of dulaglutide treatment (blunting nicotine withdrawal symptoms and reducing post-cessational weight gain). This project is of high relevance as it explores novel treatment options aimed at preventing the disastrous consequences of nicotine consumption and obesity.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03204396 . Registered on June 26, 2017.

Do Weight Changes Affect the Association between Smoking Cessation and the Risk of Stroke Subtypes in Korean Males?

(1) Background: We investigated whether weight changes affect the association between smoking cessation and stroke risk; (2) Methods: Overall, 719,040 males were categorized into eight groups according to smoking status (sustained smokers, non-smokers, long-term quitters (quit > 4 years), and recent quitters (quit < 4 years)) and post-cessation weight change (-5 kg, -5.0 to 0.1 kg, maintainers, 0.1-5.0 kg, and >5.0 kg). The hazard ratios (HR) and 95% confidence intervals (CI) for incident total, ischemic, and hemorrhagic strokes, including subarachnoid and intracerebral hemorrhage, were calculated using Cox proportional hazard models; (3) Results: We detected 38,730 strokes (median follow-up, 25.7 years), including 30,609 ischemic and 9055 hemorrhagic strokes. For recent quitters with a >5.0 kg or 0.1-5.0 kg weight increase, maintainers, or those who lost 0.1-5 kg, the multivariable HR for total stroke was 0.73 (95% CI, 0.67-0.79), 0.78 (95% CI, 0.74-0.82), 0.77 (95% CI, 0.69-0.85), 0.84 (95% CI, 0.77-0.90), and 1.06 (95% CI, 0.92-1.23), respectively, compared with that of sustained smokers; (4) Conclusions: Comparable patterns were obtained for stroke subtypes. Thus, we strongly recommend quitting smoking, as weight gain after quitting smoking does not alter the stroke-related benefits.

Nicotine addiction and overweight affect intrinsic neural activity and neurotransmitter activity: A fMRI study of interaction effects

BACKGROUND

Nicotine addiction and overweight often co-exist, but the neurobiological mechanism of their co-morbidity remains to be clarified. In this study, we explore how nicotine addiction and overweight affect intrinsic neural activity and neurotransmitter activity.

METHODS

This study included 54 overweight people and 54 age-, sex-, and handedness-matched normal-weight individuals, who were further divided into four groups based on nicotine addiction. We used a two-way factorial design to compare intrinsic neural activity (calculated by the fALFF method) in four groups based on resting-state functional magnetic resonance images (rs-fMRI). Furthermore, the correlation between fALFF values and PET- and SPECT-derived maps to examine specific neurotransmitter system changes underlying nicotine addiction and overweight.

RESULTS

Nicotine addiction and overweight affect intrinsic neural activity by themselves. In combination, they showed antagonistic effects in the interactive brain regions (left insula and right precuneus). Cross-modal correlations displayed that intrinsic neural activity changes in the interactive brain regions were related to the noradrenaline system (NAT).

CONCLUSION

Due to the existence of interaction, nicotine partially restored the changes of spontaneous activity in the interactive brain regions of overweight people. Therefore, when studying one factor alone, the other should be used as a control variable. Besides, this work links the noradrenaline system with intrinsic neural activity in overweight nicotine addicts. By examining the interactions between nicotine addiction and overweight from neuroimaging and molecular perspectives, this study provides some ideas for the treatment of both co-morbidities.

Tryptophan and Substance Abuse: Mechanisms and Impact

Addiction, the continuous misuse of addictive material, causes long-term dysfunction in the neurological system. It substantially affects the control strength of reward, memory, and motivation. Addictive substances (alcohol, marijuana, caffeine, heroin, methamphetamine (METH), and nicotine) are highly active central nervous stimulants. Addiction leads to severe health issues, including cardiovascular diseases, serious infections, and pulmonary/dental diseases. Drug dependence may result in unfavorable cognitive impairments that can continue during abstinence and negatively influence recovery performance. Although addiction is a critical global health challenge with numerous consequences and complications, currently, there are no efficient options for treating drug addiction, particularly METH. Currently, novel treatment approaches such as psychological contingency management, cognitive behavioral therapy, and motivational enhancement strategies are of great interest. Herein, we evaluate the devastating impacts of different addictive substances/drugs on users' mental health and the role of tryptophan in alleviating unfavorable side effects. The tryptophan metabolites in the mammalian brain and their potential to treat compulsive abuse of addictive substances are investigated by assessing the functional effects of addictive substances on tryptophan. Future perspectives on developing promising modalities to treat addiction and the role of tryptophan and its metabolites to alleviate drug dependency are discussed.

Spirometric Parameters in Waterpipe Smokers, Cigarette Smokers, and Non-smokers of Shahedieh Cohort Study

BACKGROUND

Different kinds of smoking tobacco may affect pulmonary function and reduce some spirometric parameters. This study aimed to assess the relationship between smoking cigarettes and waterpipe and spirometric parameters.

METHODS

This was a cross-sectional study on 1543 middle-aged individuals, as a sub-study of the Shahedieh cohort study in Yazd. The participants were randomly selected from the Shahedieh cohort population and were divided into 6 groups according to their smoking habits: non-smokers (n=455), cigarette smokers (n=139), waterpipe smokers (n=287), ex-cigarette smokers (n=131), concurrent waterpipe and cigarette smokers (n=121), and cigarette or waterpipe passive smokers (n=410). Spirometry was performed on all participants and spirometric parameters were compared between different groups. The data were analyzed by SPSS (version 20) using Kolmogorov-Smirnov, Kruskal-Wallis, and Mann-Whitney U tests.

FINDINGS

FEV1 %, FEV1/FVC, and PEF25-75% were significantly lower in cigarette smokers, compared to waterpipe smokers and non-smokers. The measures were not significantly lower in waterpipe smokers in comparison to non-smokers. The frequency of obstructive pattern and small airway diseases was significantly higher in cigarette smokers compared to waterpipe smokers and non-smokers.

CONCLUSION

The results of this study showed that in the middle-aged population, spirometric parameters related to airway obstruction (FEV1, FEV1/FVC, and FEF25-75%) were significantly lower in cigarette smokers than in non-smokers and waterpipe smokers, but these parameters were not significantly different between waterpipe smokers and non-smokers.

Age is the most important factor for change in body mass index and waist circumference in older people in southern Brazil

OBJECTIVES

The aim of this study is to assess the changes in body mass index and waist circumference (WC) and their associations with sociodemographic, behavioral, and health characteristics in non-institutionalized older people in southern Brazil over a period of ≤6 y.

METHODS

This is a prospective study, with interviews conducted in 2014 and in 2019 to 2020. Of the 1451 individuals from Pelotas, Brazil, aged >60 y and interviewed in 2014, 537 were reevaluated in 2019 to 2020. An increase or decrease was defined as a variation of ≥5% in body mass index and WC in the second visit compared with the first. The association with changes in outcomes was assessed according to sociodemographic, behavioral, and health characteristics using multinomial logistic regression.

RESULTS

Approximately 29% of the older participants lost body mass. Regarding WC, there was an increase in 25.6% in the older participants. The older participants ages ≥80 y had greater odds of losing body mass (odds ratio [OR] = 4.73; 95% confidence interval [CI], 2.29-9.76) and of reducing WC (OR = 2.84; 95% CI, 1.59-6.94). Former smokers had, on average, 41% and 64% lower odds of losing and gaining body mass (95% CI, 0.37-0.95 and 95% CI, 0.19-0.68, respectively), and those who were on ≥5 medications had greater odds of gaining body mass (OR = 1.92; 95% CI, 1.12-3.28) and WC (OR = 1.79; 95% CI, 1.18-2.74).

CONCLUSIONS

Despite the high proportion of older people who kept their body mass index and WC stable during this period, many of them lost body mass and gained WC. The findings also highlighted the importance of age in the nutritional changes observed in the population.

Prevalence of Cardiovascular Risk Factors in Middle-Aged Lithuanian Men Based on Body Mass Index and Waist Circumference Group Results from the 2006-2016 Lithuanian High Cardiovascular Risk Prevention Program

Background and aims: This study aimed to estimate the prevalence of cardiovascular risk factors in middle-aged Lithuanian men categorized according to body mass index and waist circumference results. Methods and results: The data were from the Lithuanian High Cardiovascular Risk primary prevention program between 2009 and 2016. This community-based cross-sectional study comprised 38,412 men aged 40 to 54 years old. We compared the prevalence of arterial hypertension, dyslipidaemia, diabetes mellitus, smoking, and metabolic syndrome in body mass index (BMI) and waist circumference (WC) groups. Regarding the allometric anthropometrics for WC, A Body Shape Indices (ABSIs) were analyzed with respect to mortality risk and smoking status. The most prevalent risk factor in men was dyslipidaemia, followed by arterial hypertension and smoking (86.96%, 47.94%, and 40.52%, respectively). All risk factors except for smoking were more prevalent in men with overweight or obesity as measured by BMI compared to men with normal weight. Similarly, smoking was the only cardiovascular risk factor that was more prevalent among subjects with normal WC compared to those with increased WC or abdominal obesity. Elevated ABSI, which is associated with higher mortality risk, was more prevalent in smokers. Conclusion: The most prevalent cardiovascular risk factor among middle-aged Lithuanian men was dyslipidaemia, with a surprisingly high prevalence in all BMI and WC groups. Smoking was the only risk factor most prevalent in subjects with low or normal weight according to BMI. It was also more prevalent in the normal WC group compared to the increased WC or abdominal obesity groups, but ABSI values associated with higher mortality were more prevalent among smokers than non-smokers.

Variations in the patterns of tobacco usage among indian females - findings from the global adult tobacco survey India

Background

Males dominate in tobacco usage, as well as in tobacco research, knowing that women face more severe health consequences. There is a specific lack of information on epidemiological statistics, risks, and the level of knowledge among women regarding tobacco. This study examines the Global Adult Tobacco Survey (GATS)-India dataset to estimate female tobacco usage and assess socio-economic variations in tobacco consumption, awareness regarding the adverse effects of tobacco, noticing pack health warnings (PHW), and intention to quit tobacco use well as factors influencing these domains.

Methods

Using a geographically clustered multistage sampling method, the nationally representative GATS II (2016–17) interviewed 40,265 female respondents aged 15 years and above from all Indian states and union territories. Standard operational definitions were used to estimate the primary independent variables (community, individual, and household categories) and dependent variables like awareness regarding the adverse effects of tobacco, noticing pack health warning (PHW), and intention to quit tobacco. Sampling weights were adjusted while performing the analysis. Bivariate and multivariable analysis were used to generate the estimates.

Results

Of the total female respondents, 84.2% were never-users, 13.3% ever consumed Smokeless Tobacco (SLT) products, 1.8% ever smoked tobacco, and 0.8% were dual users once in their lives. Around 16% of the women had exposure to Second Hand Smoke (SHS) either at their homes, workplaces or in public places. Overall, maximum awareness was seen among non-smoker females (64.7%) and dual users (64.7%), followed by women exposed to SHS, SLT users, and smokers. PHW was noticed more by the bidi smokers, followed by SLT users and cigarette smokers. Factors that positively affected intention to quit smoking included younger age, secondary school education, self-employed status, the habit of buying packed cigarettes/bidi, believing that smoking causes serious illness, and attempted quitting in the last 12 months.

Conclusion

A high proportion of women consume tobacco which is significantly influenced by socio-demographic factors. Tobacco regulators should be especially concerned about women as the tobacco marketing experts target them. Mobilizing self-help groups and organizations working for women and children could assist broader campaigns to generate awareness and motivate quitting attempts.

The Effect of Smoking Cessation on Body Weight and Other Metabolic Parameters with Focus on People with Type 2 Diabetes Mellitus

Smokers with diabetes mellitus substantially lower their risks of microvascular and macrovascular diabetic complications, in particular cardiovascular disease, by quitting smoking. However, subsequent post-smoking-cessation weight gain may attenuate some of the beneficial effects of smoking cessation and discourage attempts to quit. Weight gain can temporarily exacerbate diabetes and deteriorate glycemic control and metabolic profile. The molecular mechanisms by which quitting smoking leads to weight gain are largely associated with the removal of nicotine's effects on the central nervous system. This review addresses mechanisms of post-smoking-cessation weight gain, by reviewing the effects of nicotine on appetite, food intake, eating behaviour, energy expenditure, fat oxidation and appetite-regulating peptides. We also highlight correlations between post-cessation weight gain and risk of type 2 diabetes, consequences of weight gain in people with type 2 diabetes and the role of pharmacotherapies, which combine treatment of nicotine addiction and promotion of weight control.

Smoking-induced microbial dysbiosis in health and disease

Smoking is associated with an increased risk of cancer, pulmonary and cardiovascular diseases, but the precise mechanisms by which such risk is mediated remain poorly understood. Additionally, smoking can impact the oral, nasal, oropharyngeal, lung and gut microbiome composition, function, and secreted molecule repertoire. Microbiome changes induced by smoking can bear direct consequences on smoking-related illnesses. Moreover, smoking-associated dysbiosis may modulate weight gain development following smoking cessation. Here, we review the implications of cigarette smoking on microbiome community structure and function. In addition, we highlight the potential impacts of microbial dysbiosis on smoking-related diseases. We discuss challenges in studying host–microbiome interactions in the context of smoking, such as the correlations with smoking-related disease severity versus causation and mechanism. In all, understanding the microbiome’s role in the pathophysiology of smoking-related diseases may promote the development of rational therapies for smoking- and smoking cessation-related disorders, as well as assist in smoking abstinence.

Tobacco cessation in patients with multiple chronic conditions: nutritional strategies as an additional tool in treatment

OBJECTIVE

To evaluate the impacts of a nutritional education intervention for patients with multiple chronic conditions during smoking cessation.

METHODS

The non-probabilistic sample comprised 18 adults and seniors of both sexes recruited from a smoking cessation treatment group. At the beginning of treatment, smoking history, degree of dependence, and stage of motivation were assessed. Degree of craving was evaluated weekly for the 1st month. Anthropometric and biochemical assessments were conducted at baseline, at 1 month, and at 3 months. Dietary intake was assessed with the "How is your diet?" questionnaire. The nutritional intervention was delivered in three sessions. The themes covered were energy balance and physical activity, healthy eating, and the importance of fruit and vegetables in the diet. Statistical analysis was conducted with the Shapiro Wilk test of normality, the paired t test, and the Wilcoxon or Mann-Whitney U tests (significance ≤ 0.05).

RESULTS

Most people (55.6%) in the intervention group had a high degree of smoking dependence, while the frequency in the control group was 22.2%. Degree of craving decreased significantly after 1 month of treatment (p = 0.017). After 3 months, both groups had a positive variation in mean body weight, although below 3%. In both groups, the average percentage of weight gain was less than 3%, suggesting that delivery of the nutritional education sessions and the nutritionist's use of the protocol proposed by the Instituto Nacional de Câncer (INCA) helped to control weight gain. Blood glucose and homeostasis model assessment-insulin resistance (HOMA-IR) both increased significantly in the intervention group (p = 0.15 and p = 0.50, respectively).

CONCLUSION

Greater proximity and more frequent intervention by a nutritionist assists and encourages healthy eating practices during the smoking cessation process, which can benefit individuals' control of chronic diseases over the long term.

Divergent Roles of α5 and β4 Nicotinic Receptor Subunits in Food Reward and Nicotine-induced Weight Loss in Male Mice

A major obstacle to successful smoking cessation is the prospect of weight gain. Despite a clear relationship between cigarette smoking and body weight, surprisingly little is known about the physiological and molecular mechanism by which nicotine affects energy homeostasis and food-motivated behaviors. Here we use loss-of-function mouse models to demonstrate that 2 nicotinic acetylcholine receptor (nAChR) subunits encoded by the CHRNA5-CHRNA3-CHRNB4 gene cluster, α5 and β4, exhibit divergent roles in food reward. We also reveal that β4-containing nAChRs are essential for the weight-lowering effects of nicotine in diet-induced obese mice. Finally, our data support the notion of crosstalk between incretin biology and nAChR signaling, as we demonstrate that the glycemic benefits of glucagon-like peptide-1 receptor activation partially relies on β4-containing nAChRs. Together, these data encourage further research into the role of cholinergic neurotransmission in regulating food reward and the translational pursuit of site-directed targeting of β4-containing nAChRs for treatment of metabolic disease.

Change in waist circumference and lifestyle habit factors as a predictor of metabolic risk among middle-aged and elderly Japanese people: population-based retrospective 10-year follow-up study from 2008 to 2017

Background

Waist circumference (WC) increases more than body mass index (BMI) over time. This study investigated the change in WC among middle-aged and elderly Japanese people for 10 years, and its relationship with lifestyle and lipid metabolism factor.

Methods

Health checkup data and lifestyle habits of a retrospective cohort of 745 people aged 40–65 years who underwent health checkups at least three times between 2008 and 2017 were analyzed. Information of Lifestyle habits about smoking history, regular exercise, alcohol intake skipping breakfast was collected using a self-administered questionnaire. Participants who were taking medications for diabetes, hyperlipidemia, or hypertension were excluded from analyses. Longitudinal associations between the change in WC and lifestyle habit factors with adjustments for sex, age, and WC at the start of health checkups were assessed using generalized linear models.

Results

Regardless of lifestyle, body weight (BW) decreased 0.8 kg (p < 0.001) for women, 0.9 kg (p = 0.003) for men, WC increased 0.8 cm (p = 0.007) for women, 0.2 cm (p = 0.657) for men. In addition, serum triglycerides and high- and low-density lipoprotein levels estimated 10 years later revealed that increased WC ratios also exacerbated the respective blood sample data.

Conclusion

Both men and women showed an increase in WC regardless of BW changes, and the increase in WC worsened lipid metabolism. For the middle-aged and elderly, whose WC increases over time, it will be more important to take notice of their WC than BW or BMI for effective health checkups.

Diabetogenic and Obesogenic Effects of Cadmium in Db/Db Mice and Rats at a Clinically Relevant Level of Exposure

Studies show an association between cadmium (Cd) exposure and prediabetes or type II diabetes mellitus. We have previously reported that Cd causes decreased levels of serum leptin in rats following 12 weeks of daily Cd dosing (0.6 mg/kg/b.w./day). Since leptin plays an important role in metabolism, we examined the effects of Cd on rats and db/db mice, which are deficient in leptin receptor activity. We gave rats and mice daily subcutaneous injections of saline (control) or CdCl₂ at a dose of 0.6 mg/kg of Cd for 2 weeks, followed by 2 weeks of no dosing. At the end of the 4-week study, exposure to Cd resulted in a more rapid increase in blood glucose levels following an oral glucose tolerance test in db/db vs. lean mice. During the two weeks of no Cd dosing, individual rat bodyweight gain was greater (p ≤ 0.05) in Cd-treated animals. At this time point, the combined epididymal and retroperitoneal fat pad weight was significantly greater (p ≤ 0.05) in the Cd-treated lean mice compared to saline-treated controls. Although this pilot study had relatively low N values (4 per treatment group for mice and 6 for rats) the results show that clinically relevant levels of Cd exposure resulted in diabetogenic as well as obesogenic effects.

Knowledge and attitudes on smoking cessation of e-cigarettes: a mixed-methods study of pharmacy students in Surabaya, Indonesia

Background

Pharmacy students as candidates for health workers who will take part in smoking cessation. Knowledge and attitudes of smoking cessation can help map the behavior of pharmacists in the future. This study aimed to explore knowledge and attitudes on smoking cessation of e-cigarettes with the mixed methods study of pharmacist students.

Method

This research was conducted in Januari-Juni 2021 in Surabaya. The research design was mix-method with sequential explanatory strategy. The variables were knowledge and attitudes on smoking cessation of e-cigarettes. The sample in this qualitative approach was derived from a sample of quantitative data. Respondents were interviewed in depth until the data reached the saturation level in order to obtain good and usable qualitative data.

Results

This study involved 31 respondents. The highest level of knowledge about dangers of e-cigarettes, especially related to nicotine (100% of respondents answered correctly). The highest positive level of attitude about dangers of e-cigarettes, especially e-cigarettes harmful to passive smokers (27% of respondents had positive attitude). Cigarettes were harmful to lung and cardiovascular health, regarding the dangers of passive smoking, some agree and disagree. Non-smokers didn't need to be recommended for e-cigarettes, e-cigarettes can be recommended for tobacco smokers, e-cigarettes cause addiction, and e-cigarettes can be a good recommendation for those who want to carry out smoking cessation. Regulation of e-cigarettes in Indonesia was considered to be lacking and needs to be improved.

Conclusions

Pharmacist students have a high level of knowledge and a positive attitude towards smoking cessation.

Weight Gain After Smoking Cessation and Cancer Risk in 3 Prospective Cohorts in the United States

Background

It remains unknown how cancer risks vary by duration of smoking cessation and whether the benefit is attenuated by postcessation weight gain.

Methods

We prospectively followed 198 565 persons from the Nurses’ Health Study (1978-2016), Nurses’ Health Study II (1991-2017), and Health Professionals Follow-up Study (1988-2016) who were free of cancer at baseline. We used proportional hazard Cox models to compare cancer risk between current smokers and former smokers with different durations of smoking cessation and postcessation weight gains.

Results

During 4 718 199 person-years of follow-up, we identified 32 456 cases of total cancer. Compared with current smokers, the risks for total and smoking-related cancer in past smokers were reduced to the level similar to never smokers after abstaining smoking for more than 26 years, with the hazard ratio of 0.69 (95% confidence interval [CI] = 0.63 to 0.76) for total cancer and 0.31 (95% CI = 0.26 to 0.37) for smoking-related cancer, whereas no risk reduction was found for obesity-related cancer. Comparing former smokers with current smokers, the multivariable-adjusted hazard ratios for postcessation weight gain of 0-4.9 kg, 5-9.9 kg, and 10 kg or higher were 0.85 (95% CI = 0.81 to 0.89), 0.88 (95% CI = 0.83 to 0.93), and 0.93 (95% CI = 0.88 to 1.00) for total cancer and 0.62 (95% CI = 0.58 to 0.67), 0.65 (95% CI = 0.60 to 0.71), and 0.71 (95% CI = 0.65 to 0.78) for total smoking-related cancer. In contrast, higher weight gain following smoking cessation was associated with a modest increased obesity-related cancer risk.

Conclusion

Smoking cessation overall has a strong net association with lower risk of total cancer irrespective of weight gain. However, this inverse association may be attenuated by substantial postcessation weight gain, largely because of an increased risk of obesity-related cancers.

Study on Dynamic Progression and Risk Assessment of Metabolic Syndrome Based on Multi-State Markov Model

AIM

Metabolic syndrome (MetS) coexists with the occurrence and even death of cardiovascular disease and diabetes mellitus. It is essential to study the factors in the dynamic progression of MetS in the interest of prevention and control.

PURPOSE

The aim of this study was to analyze the dynamic progression of Mets and explore the potential factors influencing the progression or reversal of MetS.

PATIENTS AND METHODS

This study involved 5581 individuals from two waves of the China Health and Retirement Longitudinal Study: 2011 and 2015. A multistate Markov model containing 4 states (free of metabolic disorder (FMD), mild metabolic disorder (MMD), severe metabolic disorder (SMD) and MetS) was adopted to study the dynamic progression of MetS and its influencing factors.

RESULTS

After follow-up, a total of 2862 cases (50.28% of the total number) had disease state transition. The intensity of transition from MetS to SMD is the same as that from SMD to MMD, and is greater than that from MMD to Mets (0.06 vs 0.05). For the MetS state, a mean of 1/0.08=12.5 years was spent in the MetS state before recovery. The exercise, smoke, drink, BMI level, hyperuricemia had statistically significant effects on progression of MetS status (P<0.05). The obesity or overweight, little exercise, smoke, drink and hyperuricemia increased the risk of forward progression of MetS disease status. There were significant nonmodifiable (age, gender) and modifiable factors (exercise, drink, BMI level, or high HbA1c) associated with reversion of MetS state.

CONCLUSION

The likelihood of progression from MMD to MetS is less likely than that of reversion from MetS to SMD and SMD to MMD. Old females were more resistant to recover from worse states than males. Prevention and intervention measures should be adopted early when MMD or SMD onset occurs.

Gut microbiota modulates weight gain in mice after discontinued smoke exposure

Cigarette smoking constitutes a leading global cause of morbidity and preventable death¹, and most active smokers report a desire or recent attempt to quit². Smoking-cessation-induced weight gain (SCWG; 4.5 kg reported to be gained on average per 6-12 months, >10 kg year^-1 in 13% of those who stopped smoking³) constitutes a major obstacle to smoking abstinence⁴, even under stable^5,6 or restricted⁷ caloric intake. Here we use a mouse model to demonstrate that smoking and cessation induce a dysbiotic state that is driven by an intestinal influx of cigarette-smoke-related metabolites. Microbiome depletion induced by treatment with antibiotics prevents SCWG. Conversely, fecal microbiome transplantation from mice previously exposed to cigarette smoke into germ-free mice naive to smoke exposure induces excessive weight gain across diets and mouse strains. Metabolically, microbiome-induced SCWG involves a concerted host and microbiome shunting of dietary choline to dimethylglycine driving increased gut energy harvest, coupled with the depletion of a cross-regulated weight-lowering metabolite, N-acetylglycine, and possibly by the effects of other differentially abundant cigarette-smoke-related metabolites. Dimethylglycine and N-acetylglycine may also modulate weight and associated adipose-tissue immunity under non-smoking conditions. Preliminary observations in a small cross-sectional human cohort support these findings, which calls for larger human trials to establish the relevance of this mechanism in active smokers. Collectively, we uncover a microbiome-dependent orchestration of SCWG that may be exploitable to improve smoking-cessation success and to correct metabolic perturbations even in non-smoking settings.

Smoking cessation and weight gain: Evidence from China

Cigarette smoking has long been viewed as a means to control body weight. However, studies on the association between smoking cessation and weight gain have reported mixed findings and, notably, there is limited evidence among the Chinese population - the world's largest smoker population. The extent to which smoking cessation is positively associated with body weight is of interest as excessive weight gain contributes to heart disease, diabetes, hypertension, musculoskeletal disorders, and some cancers. Additionally, concerns over weight gain may dissuade current smokers from quitting. Using data from the China Health and Nutrition Survey (CHNS), we examine the association between smoking cessation and body weight in China. To account for the nonrandom nature of smoking cessation, our research design relies on within-individual variation in smoking status to remove the influence of time-invariant unobserved differences across individuals that are correlated with both cessation and body weight. We find that smoking cessation is associated with a modest increase in weight (0.329 kg, 0.51 % off the mean) and no significant changes in the prevalence of overweight or obesity.

Associations of Nutritional, Lifestyle, and Metabolic Factors With Non-alcoholic Fatty Liver Disease: An Umbrella Review With More Than 380,000 Participants

Background & Aims: Nonalcoholic fatty liver disease (NAFLD) is the most common liver injury. We performed this umbrella review of meta-analyses to summarize the evidence on the associations of nutritional, lifestyle, and metabolic factors with NAFLD.

Methods: We searched the PubMed, Embase, and Web of Science databases from inception until July 2, 2020, to identify meta-analyses of observational studies which explored the associations of nutritional, lifestyle, and metabolic factors with NAFLD. Evidence levels were assessed using summary effect sizes, 95% prediction intervals, between-study heterogeneity, evidence of small-study effects, and evidence of excess significance bias for each meta-analysis. (No. of PROSPERO, CRD42020200124).

Results: Twenty two risk or protective factors from 10 published meta-analyses were included and studied. Three risk factors (sugar-sweetened beverage consumption, serum fetuin-A, and waist circumference) with highly suggestive levels of evidence and three risk factors (soft drink consumption, former smoking, and body mass index) with suggestive levels of evidence were identified. Only two protective factors (physical activity and serum vitamin D level [among adults in Western countries]) with suggestive levels of evidence were identified. Furthermore, other six risk factors and two protective factors with weak levels of evidence were identified.

Conclusions: We found varying levels of evidence of associations of nutritional, lifestyle, and metabolic factors and NAFLD. The results suggest that nutritional and lifestyle management should be considered as a major primary preventive strategy for NAFLD. Moreover, considering the low quality of included meta-analyses and limited area of research topics, future high-quality original studies and meta-analyses should be performed to study these associations.

Tobacco consumption in Chilean university students and associations with anthropometry, eating habits and sleep quality multicentric study

Tobacco Consumption (TC) is one of the main causes of the deterioration of health; however, there are few studies linking its consumption with diet and nutrition among university students. The objective of this study is to test the association of smoking with anthropometry, diet and sleep quality among Chilean university students. Cross-sectional study. University students (n = 1454) from the North, South and Central parts of Chile were evaluated. A self-assessment survey was used to evaluate healthy and unhealthy eating habits. Nutritional status was evaluated by Body Mass Index (BMI). Two surveys were used to assess sleep quality: the Questionnaire of Insomnia and the Epworth Scale. Finally, participants were consulted about Tobacco Consumption: 30% of the students consume tobacco and have a higher score in unhealthy food consumption, less frequent weekly breakfast consumption (< 0.01), lower daily fruit (< 0.01) and vegetables (< 0.05) consumption, higher alcohol consumption (< 0.05) and daily junk food consumption (< 0.05) compared to non-consuming students. Men who consume tobacco present greater insomnia (< 0.001), sleep latency (< 0.001) and daytime sleepiness (< 0.05) compared to non-consumers; and women who consume tobacco have a higher weight (< 0.001) and BMI (< 0.01). When performing logistic regression, tobacco consumption is positively associated with major alcohol consumption (< 0.001), whereas fish (< 0.05) and vegetable (< 0.05) consumption was negatively associated. In conclusion, students of both sexes who smoke have more unfavorable health factors and a poorer quality of life.

Cigarette smoking and nicotine exposure contributes for aberrant insulin signaling and cardiometabolic disorders

Cigarette smoking- and nicotine-mediated dysregulation in insulin-signaling pathways are becoming leading health issues associated with morbidity and mortality worldwide. Many cardiometabolic disorders particularly insulin resistance, polycystic ovary syndrome (PCOS), central obesity and cardiovascular diseases are initiated from exposure of exogenous substances which augment by disturbances in insulin signaling cascade. Among these exogenous substances, nicotine and cigarette smoking are potential triggers for impairment of insulin-signaling pathways. Further, this aberrant insulin signaling is associated with many metabolic complications, which consequently give rise to initiation as well as progression of these metabolic syndromes. Hence, understanding the underlying molecular mechanisms responsible for cigarette smoking- and nicotine-induced altered insulin signaling pathways and subsequent participation in several health hazards are quite essential for prophylaxis and combating these complications. In this article, we have focused on the role of nicotine and cigarette smoking mediated pathological signaling; for instance, nicotine-mediated inhibition of nuclear factor erythroid 2-related factor 2 and oxidative damage, elevated cortisol that may promote central obesity, association PCOS and oxidative stress via diminished nitric oxide which may lead to endothelial dysfunction and vascular inflammation. Pathological underlying molecular mechanisms involved in mediating these metabolic syndromes via alteration of insulin signaling cascade and possible molecular mechanism responsible for these consequences on nicotine exposure have also been discussed.

No changes in dietary intake after quitting smoking; a prospective study in Switzerland

BACKGROUND

After quitting smoking, quitters frequently increase their weight and change their dietary intake. Still, most studies on the topic are over 20 years old and focused on few dietary markers. We analysed the changes in weight and dietary intake after quitting smoking using a large panel of dietary markers.

METHODS

Prospective study including 5064 participants, 169 of whom (3.3%) quitted during a median follow-up of 5 years. Dietary intake was assessed using a food frequency questionnaire. Participants were excluded if they lacked dietary data or reported extreme total energy intakes (TEI) < 850 or > 4000 kcal/day.

RESULTS

Data from 128 participants (43.8% women, aged 56.0 ± 10.0 years) were used. After quitting smoking, mean weight increased 2.1 ± 0.7 kg; the majority (58%) of the participants gained over 1 kg, and only 7.1% were on a diet to reduce their weight. Total protein intake increased from (median [interquartile range]) 14.4 [12.9-16.4] to 15.1 [13.4-17.9] % of total energy intake (TEI), p = 0.008, while animal protein intake increased from 9.7 [8.0-12.1] to 10.8 [8.5-13.5] %TEI, p = 0.011. Fish intake increased from 27 [17-45] to 37 [19-55] g/day, p = 0.016 and dairy intake decreased from 177 [94-288] to 150 [77-243] g/day, p = 0.009. No other changes were found. Among the 68 (53%) participants who reported time since quitting, quitting for <=1 year led to a decreased consumption of fruits, while the opposite was found for participants who quit for longer than one year. No associations were found between weight or dietary changes and time since quitting.

CONCLUSIONS

People who quit smoking tend to gain weight, do not significantly change their dietary intake, and seem to make little effort to prevent weight gain. Systematic dietary support should be provided to all smokers wishing to quit.

Smoking cessation, weight gain, cardiovascular risk, and all-cause mortality: a meta-analysis

OBJECTIVE

Quitting smoking usually results in weight gain, rising the concern that weight gain after smoking cessation may attenuate the benefits of smoking quitting on cardiovascular health. We aimed to examine the risk of cardiovascular disease (CVD) among smoking quitters compared with smokers, stratified by post-cessation weight change.

METHODS

We searched PubMed, Scopus, and Web of Science for eligible studies published before September 2020. Cohort studies examining the relative risk (RR) of CVD among smoking quitters stratified by post-cessation weight change, with smokers being treated as the reference, were included. Two investigators extracted the key characteristics of each included study using a standard electronic form.

RESULTS

We identified 9 studies for this meta-analysis. Compared with smokers, the pooled RRs (95% confidence interval) of CVD among quitters with weight gain and among those without were 0.74 [0.66, 0.83]) and 0.86 [0.80, 0.92]), with no evidence of heterogeneity between studies being observed. Moreover, the associations appeared to be significantly stronger among quitters with weight gain than those without, particularly in the analysis of coronary heart disease and stroke (pooled RRs = 0.65 [0.59, 0.71] vs. 0.79 [0.71, 0.88] for coronary heart disease and 0.67 [0.62, 0.73] vs. 0.76 [0.72, 0.81] for stroke, respectively; P for interaction < 0.05).

CONCLUSIONS

Smoking cessation was associated with a significantly lower risk of CVD and all-cause mortality, regardless of post-cessation weight gain. A greater risk reduction among quitters with weight gain than those without merits further investigations.

Weight Gain After Smoking Cessation and Risk of Major Chronic Diseases and Mortality

IMPORTANCE

Smoking cessation is frequently followed by weight gain; however, whether weight gain after quitting reduces the health benefits of quitting is unclear.

OBJECTIVE

To examine the association between weight change after smoking cessation and the risk of cardiovascular diseases (CVD), type 2 diabetes, cancer, chronic obstructive pulmonary disease (COPD), and all-cause mortality.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study analyzed data from a nationally representative sample of Australian adults aged 18 years or older who were studied between 2006 and 2014. Smoking status and anthropometric measurements were self-reported annually. Cox proportional hazards regressions were used to determine the hazard ratios (HRs) for the association between changes in weight and body mass index (BMI) and the risk of CVD, type 2 diabetes, cancer, COPD, and mortality. Data were analyzed in January 2019.

EXPOSURES

Annual self-reported smoking status; years since quitting.

MAIN OUTCOMES AND MEASURES

Weight gain after quitting, incident CVD, type 2 diabetes, cancer, COPD, and all-cause mortality.

RESULTS

Of a total 16 663 participants (8082 men and 8581 women; mean [SD] age, 43.7 [16.3] years), those who quit smoking had greater increases in weight (mean difference [MD], 3.14 kg; 95% CI, 1.39-4.87) and BMI (MD, 0.82; 95% CI, 0.21-1.44) than continuing smokers. Compared with continuing smokers, the HRs for death were 0.50 (95% CI, 0.36-0.68) among quitters who lost weight, 0.79 (95% CI, 0.51-0.98) among quitters without weight change, 0.33 (95% CI, 0.21-0.51) among quitters who gained 0.1 to 5.0 kg, 0.24 (95% CI, 0.11-0.53) among quitters who gained 5.1 to 10 kg, and 0.36 (95% CI, 0.16-0.82) among quitters who gained more than 10 kg. The HRs for death were 0.61 (95% CI, 0.45-0.83) among quitters who lost BMI, 0.86 (95% CI, 0.51-1.44) among quitters without change in BMI, 0.32 (95% CI, 0.21-0.50) among quitters who gained up to 2 in BMI, and 0.26 (95% CI, 0.16-0.45) among quitters who gained more than 2 in BMI.

CONCLUSIONS AND RELEVANCE

This cohort study found that smoking cessation was accompanied by a substantial weight gain; however, this was not associated with an increased risk of chronic diseases or an attenuation of the mortality benefit of cessation.

Two Weeks of Smoking Cessation Reverse Cigarette Smoke-Induced Skeletal Muscle Atrophy and Mitochondrial Dysfunction in Mice

INTRODUCTION

Apart from its adverse effects on the respiratory system, cigarette smoking also induces skeletal muscle atrophy and dysfunction. Whether short-term smoking cessation can restore muscle mass and function is unknown. We, therefore, studied the impact of 1- and 2-week smoking cessation on skeletal muscles in a mouse model.

METHODS

Male mice were divided into four groups: Air-exposed (14 weeks); cigarette smoke (CS)-exposed (14 weeks); CS-exposed (13 weeks) followed by 1-week cessation; CS-exposed (12 weeks) followed by 2 weeks cessation to examine exercise capacity, physical activity levels, body composition, muscle function, capillarization, mitochondrial function and protein expression in the soleus, plantaris, and diaphragm muscles.

RESULTS

CS-induced loss of body and muscle mass was significantly improved within 1 week of cessation due to increased lean and fat mass. Mitochondrial respiration and protein levels of the respiratory complexes in the soleus were lower in CS-exposed mice, but similar to control values after 2 weeks of cessation. Exposing isolated soleus muscles to CS extracts reduced mitochondrial respiration that was reversed after removing the extract. While physical activity was reduced in all groups, exercise capacity, limb muscle force, fatigue resistance, fiber size and capillarization, and diaphragm cytoplasmic HIF-1α were unaltered by CS-exposure. However, CS-induced diaphragm atrophy and increased capillary density were not seen after 2 weeks of smoking cessation.

CONCLUSION

In male mice, 2 weeks of smoking cessation reversed smoking-induced mitochondrial dysfunction, limb muscle mass loss, and diaphragm muscle atrophy, highlighting immediate benefits of cessation on skeletal muscles.

IMPLICATIONS

Our study demonstrates that CS-induced skeletal muscle mitochondrial dysfunction and atrophy are significantly improved by 2 weeks of cessation in male mice. We show for the first time that smoking cessation as short as 1 to 2 weeks is associated with immediate beneficial effects on skeletal muscle structure and function with the diaphragm being particularly sensitive to CS-exposure and cessation. This could help motivate smokers to quit smoking as early as possible. The knowledge that smoking cessation has potential positive extrapulmonary effects is particularly relevant for patients referred to rehabilitation programs and those admitted to hospitals suffering from acute or chronic muscle deterioration yet struggling with smoking cessation.

Socioeconomic deprivation, technology use, C-peptide, smoking and other predictors of glycaemic control in adults with type 1 diabetes

AIMS

Intensive glycaemic control is associated with substantial health benefits in people with type 1 diabetes. We sought to examine clinical and demographic factors associated with meeting glycaemic targets in type 1 diabetes.

METHODS

We conducted a cross-sectional analysis of 4594 individuals with type 1 diabetes. The primary outcome of the study was assessing factors associated with meeting HbA_1c targets. Secondary endpoints included factors associated with continuous subcutaneous insulin infusion (CSII) use and persistent C-peptide secretion.

RESULTS

Socioeconomic deprivation was strongly associated with a lower likelihood of achieving an HbA_1c <58 mmol/mol (7.5%) (20% in the most deprived quintile vs. 40% in the least deprived, p < 0.001). In multivariate analysis, absence of smoking history (OR 3.06, p < 0.001), flash monitoring (OR 1.49, p < 0.001), CSII (1.43, p = 0.022) and longer diabetes duration (OR 1.02 per year, p = 0.004) were independently associated with achieving HbA_1c <58 mmol/mol (7.5%), whereas increasing age (OR 0.99 per year, p = 0.004) and C-peptide <50 pM (OR 0.58, p < 0.001) were associated with a lower likelihood of meeting this target. Low C-peptide (<50 pM) was less likely in men (OR 0.55, p < 0.001) and never smokers (0.44, p < 0.001) in multivariate analysis.

CONCLUSIONS

Lower levels of deprivation, non-smoking, higher C-peptide, technology use, lower BMI and male gender were all associated with a higher likelihood of meeting HbA_1c targets. Access to proven diabetes treatments is lower in the most deprived individuals. Urgent efforts are required to provide treatments which are effective across the socioeconomic gradient.

Smoking Cessation, Weight Change, Diabetes, and Hypertension in Korean Adults

INTRODUCTION

This study investigates the association of smoking cessation and postcessation weight gain with the development of type 2 diabetes mellitus and hypertension.

METHODS

A total of 96,524 individuals without diabetes mellitus and hypertension aged ≥20 years between 2006 and 2008 were included, with follow-up until December 31, 2015. Smoking status and weight changes were monitored for 2 years. Hazard ratios and 95% CIs were calculated for the respective risks of the 2 conditions. Analyses were completed in 2020.

RESULTS

Compared with current smokers, the adjusted hazard ratios for the risk of type 2 diabetes and hypertension were 0.90 (95% CI=0.85, 0.96) and 1.00 (95% CI=0.95, 1.05) in recent quitters, 0.89 (95% CI=0.84, 0.95) and 0.92 (95% CI=0.88, 0.97) in long-term quitters, and 0.82 (95% CI=0.78, 0.86) and 0.92 (95% CI=0.89, 0.95) in never smokers. Compared with current smokers, the adjusted hazard ratios for the risk of type 2 diabetes and hypertension were 0.86 (95% CI=0.80, 0.93) and 0.98 (95% CI=0.92, 1.04) in recent quitters with no weight gain, 0.94 (95% CI=0.87, 1.03) and 1.00 (95% CI=0.94, 1.07) in those with 0.1-5 kg weight gain, 0.93 (95% CI=0.73, 1.19) and 1.14 (95% CI=0.96, 1.36) in those with 5.1-10 kg weight gain, and 1.49 (95% CI=0.84, 2.62) and 1.10 (95% CI=0.68, 1.77) in those with a weight gain of >10 kg.

CONCLUSIONS

Smoking cessation with no subsequent weight gain is associated with a reduced risk of developing type 2 diabetes. However, weight gain after smoking cessation attenuates the reduced risk of type 2 diabetes. The association between recent quitting and incident hypertension was nonsignificant, whereas long-term quitters had reduced risk of developing hypertension and type 2 diabetes.

Gender differences within the barriers to smoking cessation and the preferences for interventions in primary care a qualitative study using focus groups in The Hague, The Netherlands

OBJECTIVES

This research aimed to provide a deeper insight into the gender-specific barriers to smoking cessation and gender-specific preferences for interventions in primary care, in order to contribute to better aligned cessation care for women.

DESIGN

Qualitative study using focus groups.

SETTING

Regularly smoking female and male adults were recruited from four different general practices in The Hague (The Netherlands).

PARTICIPANTS

A total of 11 women and nine men participated. Participants included were regular smokers with a minimum age of 18 and sufficient command of the Dutch language, who were willing to talk about smoking cessation. Inclusion ended when saturation was reached for both women and men. Participants were selected by means of purposeful sampling, whereby looking at age, educational level and experience with quitting.

RESULTS

The main barriers to smoking cessation in women were psychological factors, such as emotion and stress, compared with environmental factors in men. Women indicated they were in need of support and positivity, and both women and men expressed the desire for assistance without judgement. Contrary to men, women were not drawn to restrictions and (dis)incentives.

CONCLUSION

When counselling smokers, in women the focus should be on perceived internal problems, as opposed to more external obstacles in men. Contrary to men, female smokers seem to prefer non-coercive interventions, such as a group intervention offering support and positivity. Future research should focus on these gender differences, and how they could improve treatment in primary care.

The Interdependence of Blood Pressure and Glucose in Vietnam

INTRODUCTION

Modelling of associations of systolic blood pressure (BP) and blood glucose (BG) with their explanatory factors in separate regressions treats them as having independent biological mechanisms. This can lead to statistical inferences that are unreliable because the substantial overlap in their etiologic and disease mechanisms is ignored.

AIM

This study aimed to examine the relationship of systolic blood pressure (BP) and blood glucose (BG) with measures of obesity and central fat distribution and other factors whilst taking account of the inter-dependence between them.

METHODS

Participants (n = 14706, 53.5 % females) aged 25-64 years were selected by multi-stage stratified cluster sampling from eight provinces each representing one of the eight geographical regions of Vietnam. Measurements were made using the World Health Organization STEPS protocols.

RESULTS

Structural modelling identified direct effects for BG (men P = 0.000, women P = 0.029), age (men P = 0.000, women P = 0.000) and body mass index (BMI) (men P = 0.000, women P = 0.000) in the estimation of systolic BP, and for systolic BP (men P = 0.036, women P = 0.000) and waist circumference (WC) (men P = 0.032, women P = 0.009) in the estimation of BG. There were indirect effects of age, cholesterol, physical activity and tobacco smoking via their influence on WC and BMI. The errors in estimation of systolic BP and BG were correlated (men P = 0.000, women P = 0.004), the stability indices (men 0.466, women 0.495) showed the non-recursive models were stable, and the proportion of variance explained was mid-range (men 0.553, women 0.579).

CONCLUSION

This study provided statistical evidence of a feedback loop between systolic BP and BG. BMI and WC were confirmed to be their primary explanatory factors. Saturated fat intake and physical activity were identified as possible targets of intervention for overweight and obesity, and indirectly for reducing systolic BP and BG. Harmful/hazardous alcohol intake was identified as a target of intervention for systolic BP.

Smoking Cessation, Weight Gain, and the Trajectory of Estimated Risk of Coronary Heart Disease: 8-Year Follow-up From a Prospective Cohort Study

Introduction

The effect of weight gain following smoking cessation on cardiovascular risks is unclear. We aimed to prospectively investigate the association of weight gain following smoking cessation with the trajectory of estimated risks of coronary heart disease (CHD).

Methods

In a cohort of 18 562 Japanese male employees aged 30–64 years and initially free of cardiovascular diseases, participants were exclusively grouped into sustained smokers, quitters with weight gain (body weight increase ≥5%), quitters without weight gain (body weight increase <5% or weight loss), and never smokers. Global 10-year CHD risk was annually estimated by using a well-validated prediction model for the Japanese population. Linear mixed models and piecewise linear mixed models were used to compare changes in the estimated 10-year CHD risk by smoking status and weight change following smoking cessation.

Results

During a maximum of 8-year follow-up, both quitters with and without weight gain had a substantially decreased level of estimated 10-year CHD risk after quitting smoking, compared with sustained smokers (all ps for mean differences < .001). The estimated 10-year CHD risk within the first year after cessation decreased more rapidly in quitters without weight gain than in quitters with weight gain (change rate [95% confidence interval, CI] −0.90 [−1.04 to −0.75] vs. −0.40 [−0.60 to −0.19] % per year, p < .0001). Thereafter, the estimated 10-year CHD risk in both groups increased at similar rates (change rate [95% CI] −0.07 [−0.21 to 0.07] vs. 0.11 [−0.09 to 0.30] % per year, p = .16, from year 1 to year 2; and 0.10 [0.05 to 0.15] vs. 0.11 [0.04 to 0.18] % per year, p = .80, from year 2 to year 8).

Conclusions

In this population of middle-aged, Japanese male workers, smoking cessation greatly reduces the estimated 10-year risk of CHD. However, weight gain weakens the beneficial effect of quitting smoking in a temporary and limited fashion.

Implications

To the best of our knowledge, this study is the first to examine the effect of weight gain following smoking cessation on the trajectory of the absolute risk of CHD. Our data imply that the benefits of cessation for reducing the absolute risk of CHD outweigh the potential risk increase due to weight gain, and suggest that in order to maximize the beneficial effects of quitting smoking, interventions to control post-cessation weight gain might be warranted.

A multi-stakeholder approach to eHealth development: Promoting sustained healthy living among cardiovascular patients

BACKGROUND

Healthy living is key in the prevention and rehabilitation of cardiovascular disease (CVD). Yet, supporting and maintaining a healthy lifestyle is exceptionally difficult and people differ in their needs regarding optimal support for healthy lifestyle interventions.

OBJECTIVE

The goals of this study were threefold: to uncover stakeholders' needs and preferences, to translate these to core values, and develop eHealth technology based on these core values. Our primary research question is: What type of eHealth application to support healthy living among people with (a high risk of) CVD would provide the greatest benefit for all stakeholders?

METHODS

User-centered design principles from the CeHRes roadmap for eHealth development were followed to guide the uncovering of important stakeholder values. Data were synthesized from various qualitative studies (i.e., literature studies, interviews, think-aloud sessions, focus groups) and usability tests (i.e., heuristic evaluation, cognitive walkthrough, think aloud study). We also developed an innovative application evaluation tool to perform a competitor analysis on 33 eHealth applications. Finally, to make sure to take into account all end-users needs and preferences in eHealth technology development, we created personas and a customer journey.

RESULTS

We uncovered 10 universal values to which eHealth-based initiatives to support healthy living in the context of CVD prevention and rehabilitation should adhere to (e.g., providing social support, stimulating intrinsic motivation, offering continuity of care). These values were translated to 14 desired core attributes and then prototype designs. Interestingly, we found that the primary attribute of good eHealth technology was not a single intervention principle, but rather that the technology should be in the form of a digital platform disseminating various interventions, i.e., a 'one-stop-shop'.

CONCLUSION

Various stakeholders in the field of cardiovascular prevention and rehabilitation may benefit most from utilizing one personalized eHealth platform that integrates a variety of evidence-based interventions, rather than a new tool. Instead of a one-size-fits-all approach, this digital platform should aid the matchmaking between patients and specific interventions based on personal characteristics and preferences.

Nicotine Synergizes with High-Fat Diet to Induce an Anti-Inflammatory Microenvironment to Promote Breast Tumor Growth

Breast cancer results from a complex interplay of genetics and environment that alters immune and inflammatory systems to promote tumorigenesis. Obesity and cigarette smoking are well-known risk factors associated breast cancer development. Nicotine known to decrease inflammatory signals also modulates immune responses that favor breast cancer development. However, the mechanisms by which nicotine and obesity contribute to breast cancer remain poorly understood. In this study, we examined potential mechanisms by which nicotine (NIC) and high-fat diet (HFD) promote growth of HCC70 and HCC1806 xenografts from African American (AA) triple negative (TN) breast cancer cells. Immunodeficient mice fed on HFD and treated with NIC generated larger HCC70 and HCC1806 tumors when compared to NIC or HFD alone. Increased xenograft growth in the presence of NIC and HFD was accompanied by higher levels of tissue-resident macrophage markers and anti-inflammatory cytokines including IL4, IL13, and IL10. We further validated the involvement of these players by in vitro and ex vivo experiments. We found a proinflammatory milieu with increased expression of IL6 and IL12 in xenografts with HFD. In addition, nicotine or nicotine plus HFD increased a subset of mammary cancer stem cells (MCSCs) and key adipose browning markers CD137 and TMEM26. Interestingly, there was upregulation of stress-induced pp38 MAPK and pERK1/2 in xenografts exposed to HFD alone or nicotine plus HFD. Scratch-wound assay showed marked reduction in proliferation/migration of nicotine and palmitate-treated breast cancer cells with mecamylamine (MEC), a nicotine acetylcholine receptor (nAchR) antagonist. Furthermore, xenograft development in immune-deficient mice, fed HFD plus nicotine, was reduced upon cotreatment with MEC and SB 203580, a pp38MAPK inhibitor. Our study demonstrates the presence of nicotine and HFD in facilitating an anti-inflammatory tumor microenvironment that influences breast tumor growth. This study also shows potential efficacy of combination therapy in obese breast cancer patients who smoke.

Non-Alcoholic Fatty Liver Disease Is Strongly Associated with Smoking Status and Is Improved by Smoking Cessation in Japanese Males: A Retrospective Study

BACKGROUND

Cigarette smoking is known to be a significant risk factor associated with non-alcoholic fatty liver disease (NAFLD). We aimed to examine the association between smoking status and the severity of fatty liver with regard to sex and smoking cessation.

METHODS

In total, 13,466 subjects (6,642 males and 6,824 females) who had undergone abdominal ultrasonography for health check-up, multivariable logistic regression analysis was retrospectively conducted to assess the association between smoking status and the prevalence of NAFLD stratified by sex after adjusting for other potential confounders.

RESULTS

Male sex (odds ratio [OR] 3.27, 95% confidence interval [CI] 3.00-3.57) and smoking history (former smoker: OR 1.23, 95% CI 1.10-1.38, current smoker: OR 1.31, 95% CI 1.17-1.47) were significantly associated with NAFLD. In males with a smoking history, an increased pack-year was strongly associated with the prevalence and severity of NAFLD (prevalence of moderate to severe fatty liver: Pack-year from 0.01 to 9.99, 21.3%; Pack-year from 10.00 to 19.99, 27.2%; Pack-year ≥20.00, 33.7%; P<0.0001), although the prevalence of moderate to severe fatty liver was inversely associated with the duration of smoking cessation (more than 10 years vs. within 5 years, OR 0.71, 95% CI 0.53-0.96). In female subjects, light current smoking was negatively associated with NAFLD (current smoker with a pack-year from 0.01 to 9.99 vs. never smoker, OR 0.41, 95% CI 0.19-0.76).

CONCLUSIONS

Smoking status and pack-year were strongly associated with the prevalence and severity of NAFLD, especially in Japanese males. However, smoking cessation improved NAFLD in this population.