Tobacco Smoking: Findings from 20 Years of the Tehran Lipid and Glucose Study

Cardiometabolic Profile in Young Adults With Diverse Cigarette Smoking Histories: A Longitudinal Study From Adolescence

BACKGROUND

For the first time, the present study investigated smoking trajectory and cardiometabolic profile from adolescence to young adulthood in a middle-income developing country facing a high prevalence of smoking and cardiovascular disease-related outcomes.

METHODS AND RESULTS

Data on 1082 adolescents (12-18 years of age) who participated in the TLGS (Tehran Lipid and Glucose Study) were gathered, and participants were followed for a median of 12.5 years (baseline: 1999-2002, last follow-up: 2014-2017). Participants were categorized as non/rare smokers, experimenters, and escalators using group-based trajectory models. Statistical analysis was used to compare the trajectory groups' cardiometabolic components, clinical characteristics, and cardiometabolic changes due to the individuals' placement in experimenter and escalator groups compared with non/rare smokers. The smoking trajectory groups in young adulthood differ significantly in blood pressure, triglycerides, high-density lipoprotein cholesterol, waist circumference, and body mass index, with the escalator group having the highest risk values for each component. Significant differences were observed in blood pressure (P=0.014), triglycerides (P<0.001), and waist circumference (P<0.001) status after using clinical cut points. The adjusted linear regression revealed that the escalator group had 3.16 mm Hg-lower systolic blood pressure SBP (P=0.016), 2.69 mm Hg-lower diastolic blood pressure (P=0.011), and 4.42 mg/dL-lower high-density lipoprotein cholesterol (P=0.002), compared with the non/rare smoker group.

CONCLUSIONS

Despite elevated risks in unadjusted analyses for all cardiometabolic components among smokers, our study identified a modest protective link between early smoking and blood pressure in addition to a remarkable harmful association with high-density lipoprotein cholesterol levels exclusively in the escalator group during the developmental stage to young adulthood, using adjusted analyses.

Effects of Waterpipe Smoke Exposure on Experimentally Induced Chronic Kidney Disease in Mice

Tobacco smoking is an independent risk factor in the onset of kidney disease. To date, there have been no reports on the influence of waterpipe smoke (WPS) in experimentally induced chronic kidney disease (CKD) models. We studied the effects and mechanisms of actions of WPS on a mouse model of adenine-induced CKD. Mice fed either a normal diet, or an adenine-added diet and were exposed to either air or WPS (30 min/day and 5 days/week) for four consecutive weeks. Plasma creatinine, urea and indoxyl sulfate increased and creatinine clearance decreased in adenine + WPS versus either WPS or adenine + saline groups. The urinary concentrations of kidney injury molecule-1 and adiponectin and the activities of neutrophil gelatinase-associated lipocalin and N-acetyl-β-D-glucosaminidase were augmented in adenine + WPS compared with either adenine + air or WPS groups. In the kidney tissue, several markers of oxidative stress and inflammation were higher in adenine + WPS than in either adenine + air or WPS groups. Compared with the controls, WPS inhalation in mice with CKD increased DNA damage, and urinary concentration of 8-hydroxy-2-deoxyguanosine. Furthermore, the expressions of nuclear factor κB (NF-κB) and mitogen-activated protein kinases (MAPKs) (ERK and p38) were elevated in the kidneys of adenine + WPS group, compared with the controls. Likewise, the kidneys of adenine + WPS group revealed more marked histological tubular injury, chronic inflammation and interstitial fibrosis. In conclusion, WPS inhalation aggravates kidney injury, oxidative stress, inflammation, DNA damage and fibrosis in mice with adenine-induced CKD, indicating that WPS exposure intensifies CKD. These effects were associated with a mechanism involving NF-κB, ERK and p38 activations.

Factors associated with smoking intensity among adult smokers: findings from the longitudinal cohort of the Tehran lipid and glucose study

BACKGROUND

Smoking is a significant public health problem, and there is a scarcity of documents regarding its severity, particularly in developing countries. This study aimed to determine factors related to the number of cigarettes consumed daily by adult smokers in Tehran.

METHODS

This study was conducted within the framework of the longitudinal study of Tehran Lipid and Glucose Study (TLGS). The study included 786 adult smokers living during four consecutive follow-ups from 2005 to 2016. The intensity of smoking was measured by the number of cigarettes consumed daily by adult smokers. Data analysis was done longitudinally and based on the mixed effects zero-inflated discrete Weibull (ZIDW) regression model.

RESULTS

The mean age of the individuals was 40.35 ± 12.68 years, and 643 (81.8%) of them were men. Also, 52.7% of individuals were daily smokers, 15.6% were occasional smokers, and 31.7% were non-smokers who became smokers during the study. Variables of age 1.005 (95%CI: 1.001-1.008), gender of male 1.196 (95%CI: 1.051-1.39), and marital status (divorced/widowed vs. single) 1.168 (95%CI: 1.015-1.39) were positively associated with smoking intensity. Education level (master and higher vs. illiterate) 0.675 (95%CI: 0.492-0.926)), employment status (student vs. unemployed) 0.683 (95%CI: 0.522-0.917), (housewife vs. unemployed) 0.742 (95%CI: 0.606-0.895), (Unemployed with income vs. unemployed) 0.804 (95%CI: 0.697, 0.923), implementation of smoking prohibition regulations (yes vs. no) 0.88 (95%CI: 0.843-0.932), and history of cardiovascular disease in male relatives (yes vs. no) 0.85 (95%CI: 0.771-0.951) were associated with lower smoking intensity.

CONCLUSION

We showed that demographic factors are associated with the intensity of smoking among adults and should be considered in policymakers' intervention programs to reduce smoking and quit smoking.

Interactive associations of smoking and physical activity with metabolic syndrome in adult men in Korea

Introduction

This study aimed to investigate the association of smoking and physical activity (PA) with metabolic syndrome (MetS) in adult men in Korea.

Methods

This study analyzed data of 7,229 adult men aged 19-64 years obtained from the 2014-2021 Korea National Health and Nutrition Examination Survey (KNHANES). Information on smoking habits was obtained using KNHANES data, while that on total PA (TPA), leisure-time PA (LTPA), and occupational PA (OPA) was collected using the Global Physical Activity Questionnaire. Smoking status was classified into non-smokers and smokers, and PA was categorized into three groups (total, leisure time, and occupational) according to the time spent engaging in moderate or high-intensity PA areas. The diagnosis of MetS was based on the Adult Treatment Program III of the National Cholesterol Education Program and Koreans' waist circumference criteria.

Results

Logistic regression revealed that the risk of MetS was significantly lower in non-smokers than in smokers, even after adjusting for all covariates. The risk of MetS was significantly lower in individuals who engaged in at least 150 min of moderate- and high-intensity TPA or LTPA per week than in those who did not engage in PA. Furthermore, smokers who engaged in at least 150 min of moderate- to high-intensity TPA and LTPA per week had a significantly lower risk of MetS than those who did not engage in PA. Meanwhile, OPA was not associated with MetS.

Conclusion

The findings suggest that engaging in moderate- to high-intensity TPA or LTPA for at least 150 min per week attenuates the risk of MetS caused by smoking.

Epidemiology and prevalence of tobacco use in Tehran; a report from the recruitment phase of Tehran cohort study

INTRODUCTION

Tobacco use is a major health concern worldwide, especially in low/middle-income countries. We aimed to assess the prevalence of cigarette smoking, waterpipe, and pipe use in Tehran, Iran.

METHODS

We used data from 8272 participants of the Tehran Cohort Study recruitment phase. Tobacco use was defined as a positive answer to using cigarettes, waterpipes, or pipes. Participants who did not report tobacco use during the interview but had a previous smoking history were categorized as former users. Age- and sex-weighted prevalence rates were calculated based on the national census data, and characteristics of current and former tobacco users were analyzed.

RESULTS

Age- and sex-weighted prevalence of current tobacco users, cigarette smokers, waterpipe, and pipe users in Tehran was 19.8%, 14.9%, 6.1%, and 0.5%, respectively. Current tobacco use was higher in younger individuals (35-45 years: 23.4% vs. ≥ 75 years: 10.4%, P < 0.001) and men compared to women (32.9% vs. 7.7% P < 0.001). The prevalence of tobacco use increased with more years of education (> 12 years: 19.3% vs. illiterate: 9.7%, P < 0.001), lower body mass index (< 20 kg/m²: 31.3% vs. ≥ 35 kg/m²: 13.8%, P < 0.001), higher physical activity (high: 23.0% vs. low: 16.4%, P < 0.001), opium (user: 66.6% vs. non-user: 16.5%, P < 0.001), and alcohol use (drinker: 57.5% vs. non-drinker: 15.4%, P < 0.001). Waterpipe users were younger (46.1 vs. 53.2 years) and had a narrower gender gap in prevalence than cigarette smokers (male/female ratio in waterpipe users: 2.39 vs. cigarette smokers: 5.47). Opium (OR = 5.557, P < 0.001) and alcohol consumption (OR = 4.737, P < 0.001) were strongly associated with tobacco use. Hypertension was negatively associated with tobacco use (OR = 0.774, P = 0.005).

CONCLUSION

The concerning prevalence of tobacco use in Tehran and its large gender gap for cigarette and waterpipe use warrant tailored preventive policies.

Relationships between fasting glucose levels, lifestyle factors, and metabolic parameters in Korean adults without diagnosis of diabetes mellitus

BACKGROUND

We investigated the associations between fasting glucose level ranges with lifestyle factors and metabolic profiles among adults without previous diagnosis of diabetes.

METHODS

We analyzed 13 625 adults without previous diagnosis of diabetes from the Korea National Health and Nutrition Examination Survey during 2016 to 2018. We categorized fasting glucose levels (mg/dl) as follows: <90, 90 to 99, 100 to 109, 110 to 124, and ≥125. We evaluated trends in the proportions of individuals with obesity, abdominal, obesity, current smoking, heavy drinking, and low physical activity according to these categories, and the odds for uncontrolled blood pressure (BP), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), and high-density lipoprotein cholesterol (HDL-C) for each fasting glucose level compared to a fasting glucose level of <90 mg/dl.

RESULTS

The proportions of individuals with obesity, abdominal obesity, and heavy drinking increased according to fasting glucose level (P for trend <.05). The odds for BP ≥140/90 mm Hg, TG ≥150 mg/dl, HDL-C < 40 mg/dl in men, and HDL-C < 50 mg/dl in women increased with increasing fasting glucose levels; however, the odds for LDL-C ≥ 130 mg/dl increased with increasing fasting glucose levels only in women. The increases in odds for uncontrolled BP and lipid profiles were mostly observed for fasting glucose levels ≥90 mg/dl.

CONCLUSIONS

Efforts are needed to prevent increased fasting glucose levels, as higher levels, even within normal range, were associated with poor metabolic profiles.

Lifestyle Risk Factor Assessment Through WHO STEP Approach in Tabriz, Iran

Background

The aim of this study was to assess the lifestyle behaviour and risk factors for lifestyle-related diseases in East Azerbaijan province, Iran.

Methods

A household study using a two-stage cluster sampling method was performed. Tabriz city was randomly selected for data collection among five geographic regions in the East-Azerbaijan province. Short WHO-STEP and Ultra-short version of Socio-Economic Status assessment questionnaire were used. Six hundred households were asked to respond to the STEP questionnaire.

Results

A total of 1196 people have participated in the study. People with higher socioeconomic status consumed more fruits, vegetables and fish than the people with lower socioeconomic status. People with academic education less likely to be hypertensive compared to people with non-academic education. People with a medium socioeconomic status are less likely to be hypertensive than people with high socioeconomic status. The majority of participants had poor dietary habits. In this study, 17.22%, 7.53% and 4.35% of respondents had hypertension, diabetes and depression, respectively.

Conclusion

Considering that lifestyle-related risk factors are common among people. Due to the direct link between lifestyle and the occurrence of many chronic diseases, campaigns for and training programs to implement healthy lifestyle habits are recommended.

Oxidative Stress and Inflammation Induced by Waterpipe Tobacco Smoking Despite Possible Protective Effects of Exercise Training: A Review of the Literature

The prevalence of waterpipe tobacco smoking (WTS), which is also known as ghalyan, shisha or hookah, is increasing rapidly around the world, especially among youth. Growing interest in this form of tobacco smoking can be traced, in part, to the use of flavored tobacco products, social acceptability as a safer option than cigarettes, and its consideration as a relaxation method or entertainment. However, there is a well-established association between WTS and oxidative stress that causes irreversible chronic pathological conditions such as cardiovascular and respiratory problems, as well as different types of cancers, and thus increases the risk of mortality. Clearly, induction of inflammation status through increased reactive oxygen species (ROS), which in turn leads to oxidative stress and harm to lipids, DNA, and proteins, is the most plausible mechanism to explain the potential harmful effects of WTS. Unlike WTS, well-designed exercise training programs increase ROS to the extent that it is beneficial to the body. In this study, we aimed to review available evidence on the impact of exercise training on oxidative stress and inflammation status. We also summarize the effect of acute and chronic WTS on different exercise capacities.

The First Cigarette Smoking Experience and Future Smoking Behaviors Among Adolescents with Different Parental Risk: a Longitudinal Analysis in an Urban Iranian Population

BACKGROUND

Longitudinal research among Iranian adolescent smoking is limited. The current study aimed to investigate (1) the first smoking experience (FSE) and future smoking behaviors of adolescents with different parental risk factors and (2) the association between age of the FSE and future smoking behaviors over a 12-year follow-up.

METHOD

Based on Tehran Lipid and Glucose Study (TLGS) database, 1487 adolescents (12-18 years) with complete baseline parental data were recruited. Using two-step cluster analysis, families were classified as either high or low risk; these were based on parental risk factors including age, education, employment, and smoking status. Participants were examined four times in 12 years and their data were used for survival analysis. After exclusion of 24 cases who were smokers at baseline, Cox proportional hazard modeling was used to evaluate the effect of parental clusters on the FSE in 1463 nonsmoking adolescents who completed all prospective follow-ups. Logistic regression analysis was used to examine the effect of the age of FSE on future smoking behaviors.

RESULTS

The mean age of adolescents was 14.63 ± 2.07 years at baseline. Adolescents in the high-risk cluster group were 49% more likely to try smoking for their first time, and 55% more likely to smoke in the future. Compared with girls, boys had 83% higher chance of trying their first cigarette. Moreover, 1-year delay in the FSE resulted in 25% reduction in the probability of smoking in the future.

CONCLUSION

The findings show that compared with adolescents living in low-risk families, teenagers living in high-risk families are at greater risk of smoking at an earlier age; therefore, this group could benefit from gender- and culture specific preventive interventions.

Metabolic differences between men and women who are long-term users of the water pipe: The Irbid WiHi project

Smoking tobacco and metabolic disorders are global epidemics associated with cardiovascular, immune, respiratory, and metabolic diseases. Cigarette smoking seems to affect metabolic disorders. However, the effect of water pipe (Wp), also called hookah, smoking duration on obesity and lipid profile is still a sparse. The present study examined the relationship of smoking Wp with body weight (Bw), body mass index (BMI), total cholesterol, low-density lipoprotein cholesterol (LDLc), high-density lipoprotein cholesterol (HDLc), total cholesterol/HDLc, LDLc/HDLc, and triglycerides. Obesity, lipid profile, and smoking status were obtained from a total of 291 participants of which 147 smoked Wp. Smokers were divided into 3 groups: smoked <10 years (Wp1) (n = 72), smoked 10-20 years (Wp2) (n = 43), and smoked >20 years (Wp3) (n = 30). The ANCOVA revealed greater BMI and Bw and lipid profile measures in individuals smoking Wp vs never (P < .01). Additional analysis revealed that Bw and BMI were greater in the women (n = 11) with longer Wp smoking history (P < .05) but not the men (n = 19). In addition, Tc, LDLc, Tc/HDLc, and LDLc/HDLc levels were greater among the men smoking Wp for longer time (P < .05), but not the women. In conclusion, the study found greater obesity and lipid profile in the adults smoked Wp vs never, especially the ones smoked for longer time.

Sex-specific initiation rates of tobacco smoking and its determinants among adults from a Middle Eastern population: a cohort study

OBJECTIVES

To assess the initiation rate and determinants of tobacco smoking among adults.

METHODS

In the Tehran Lipid and Glucose Study, a population-based cohort from Iran, 6101 participants ≥ 18 years old who had never smoked tobacco at baseline (phase II: 2002-2006) were followed until phase VI (2015-2018). Sex-specific initiation rates per 1000 person-years for self-reported tobacco smoking and hazard ratios (HR) for its potential determinants (using Cox proportional hazards models) were calculated.

RESULTS

The age- and sex-adjusted smoking initiation rate was 13.77 [95% confidence interval (CI) 12.59-14.94] per 1000 person-years, of which 78% was attributed to water pipe use. Initiation rate was remarkably higher among men [19.1 (16.9-21.2)] than women [8.3 (7.4-9.2)] and declined in older age-groups. Among both genders, being married was protective [men: HR 0.67 (CI 95% 0.48-0.92); women: 0.58 (0.45-0.74)], while intermediate-level education (compared with high level) [men: 1.61 (1.14-2.26); women: 1.33 (0.95-1.84, p value = 0.092)] and passive smoking [men: 1.76 (1.36-2.28); women: 1.82 (1.42-2.33)] increased the risk. Educational intervention decreased the risk among women [0.74 (0.58-0.94)].

CONCLUSIONS

The majority of adult smoking initiators started smoking with water pipe. The initiation rate was remarkably higher in men and younger age-groups. Passive smoking, being single and lower education were risk factors. Educational intervention was protective among women.

Contributions and Implications of the Tehran Lipid and Glucose Study

Tehran Lipid and Glucose Study (TLGS), an epidemiological study of non-communicable disease with 20 years follow up in a developing country in nutrition transition is a unique study in 15000 family based individuals, 3 - 75 years of age in a part of large city of Tehran. The success rate of recruitment for 20 years, intervention for lifestyle change, and thyroid, reproduction and cardiometabolic genetic studies derived from TLGS have paved suitable path towards precision medicine. In this review, baseline findings and changes of risk factors for the development of NCD including body weight, nutrition, physical activity, blood pressure, tobacco smoking, serum glucose and serum lipids as well as metabolic syndrome, chronic kidney disease, quality of life and biochemical findings in TLGS cohort have been summarized. The results of community based intervention for lifestyle change caused decreases in the prevalence of metabolic syndrome and the incidence of diabetes. It is concluded that TLGS has served as a model for other cohort studies in Iran and the region; it has helped to mobilize scientists in developing countries; it has established locally needed definitions of NCD variables; has served as a model for cohort studies in developing countries in nutrition transition with all socioeconomic constraints and has helped manpower education and development of local CVD risk scores for implementation of NCD management.