
==== Front
Rev Assoc Med Bras (1992)
Rev Assoc Med Bras (1992)
ramb
Revista da Associação Médica Brasileira
0104-4230
1806-9282
Associação Médica Brasileira

00612
10.1590/1806-9282.20240372
Original Article
Prevalence of current smoking and associated factors in older adults in Brazil
https://orcid.org/0009-0000-8836-1297
Machado José Arthur Didoné 1 *Conceptualization Data curation Writing – original draft Writing – review & editing
https://orcid.org/0009-0005-1743-6278
Fantin João Vitor 1 Conceptualization Data curation Writing – original draft Writing – review & editing
https://orcid.org/0000-0002-5897-7848
de Campos Juliana Coelho 2 Writing – original draft Writing – review & editing
https://orcid.org/0000-0001-9667-7216
Traebert Eliane 1 2 Writing – original draft Writing – review & editing
https://orcid.org/0000-0002-4099-4762
de Oliveira Cesar 3 Funding acquisition Writing – review & editing
https://orcid.org/0000-0002-7389-985X
Traebert Jefferson 1 2 Conceptualization Formal analysis Supervision Writing – original draft Writing – review & editing
1 Universidade do Sul de Santa Catarina, School of Medicine – Palhoça (SC), Brazil.
2 Universidade do Sul de Santa Catarina, Graduate Program in Health Sciences– Palhoça (SC), Brazil.
3 University College London, Department of Epidemiology and Public Health – London, United Kingdom.
*Corresponding author: josearth9@gmail.com
Conflicts of interest: the authors declare there is no conflicts of interest.

13 9 2024
2024
70 9 e2024037211 6 2024
24 6 2024
https://creativecommons.org/licenses/by/4.0/ This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
SUMMARY

OBJECTIVE:

The aim of this study was to estimate the prevalence of current smoking and its associated factors in adults aged 50 years and older in Brazil.

METHODS:

This cross-sectional study utilized data from the ELSI-Brazil study, encompassing 9,412 adults aged 50 years or over. A multivariate model using Poisson regression with a robust estimator was employed, estimating prevalence ratios and their 95% confidence intervals.

RESULTS:

The prevalence of current smoking was 17.04%. It was positively and independently associated with male gender, age up to 62 years, living without a partner, illiteracy, chronic obstructive pulmonary disease, depression, poor or very poor sleep quality, and alcohol intake more than once a month. Conversely, systemic arterial hypertension, hypercholesterolemia, diabetes mellitus, and repetitive strain injuries showed an inverse and independent association with current smoking.

CONCLUSION:

The prevalence of current smoking among adults over 50 years old in Brazil was approximately 17%, with associations found with certain sociodemographic conditions and self-reported comorbidities.

KEYWORDS:

Smoking
Older adults
Chronic disease
Aging
Tobacco
the Brazilian Ministry of Health: DECIT/SCTIE – Department of Science and Technology from the Secretariat of Science, Technology and Strategic Inputs404965/2012-1 TED 28/2017 COPID/DECIV/SAPS – Health Coordination of the Older Person in Primary Care, Department of Life Course from the Secretariat of Primary Health Care20836 22566 23700 25560 25552 27510 ELSI-Brazil was supported by the Brazilian Ministry of Health: DECIT/SCTIE – Department of Science and Technology from the Secretariat of Science, Technology and Strategic Inputs (Grants: 404965/2012-1 and TED 28/2017) and COPID/DECIV/SAPS – Health Coordination of the Older Person in Primary Care, Department of Life Course from the Secretariat of Primary Health Care (Grants: 20836, 22566, 23700, 25560, 25552, and 27510).
==== Body
pmcINTRODUCTION

Older adults are more vulnerable to chronic degenerative diseases 1 , and smoking is a risk factor closely associated with these diseases 2,3 . Worldwide, 1.14 billion people were tobacco consumers in 2019 associated with 7.69 million deaths and approximately 200 million cases of working disability 4 . Tobacco effects account for more than 300,000 deaths and 2.2 million illnesses per year in Latin America resulting in economic damage 5 .

Brazil also experienced a drop in the rate of adult smokers 6 . From 1986 onward, several tobacco control initiatives were implemented in Brazil causing a decrease in the rate from 34.8% in 1989 to 18.2% in 2008 7 and 12.8% in 2019 8 . Brazil was the second member of the World Health Organization that implemented successful laws to control tobacco use 9 .

Data from Vigitel (Brazilian Surveillance of Risk and Protective Factors for Chronic Diseases by Telephone Survey) indicated reductions across all age groups and educational levels. The most significant decreases were observed among adults aged 45–54 years, declining from 22.8% in 2006 to 9.1% in 2023 10 .

In contrast, the Brazilian Longitudinal Study of Aging (ELSI-Brazil) aimed to examine the aging process of the Brazilian population from both social and biological perspectives and its implications for adults aged 50 years or older. The objective of this study was to estimate the prevalence of current smoking and identify associated risk factors among individuals aged 50 years and older in Brazil.

METHODS

This is a cross-sectional study nested within the Brazilian Longitudinal Study of Aging (ELSI-Brazil) 11 . Our investigation used ELSI's baseline data that was collected in 2015–2016 by the Oswaldo Cruz Foundation and the Federal University of Minas Gerais. Data were collected on individuals aged 50 years or older residing in 70 municipalities across 21 states and the Federal District. The sample was designed to be representative of community-dwelling Brazilians aged 50 years or older. To ensure representation across urban and rural areas of municipalities of various sizes, the ELSI-Brazil sampling employed a multistage design. This design involved the stratification of primary sampling units (municipalities), census tracts, and households. Municipalities were divided into four strata based on population size: the first stratum (≤26,700 inhabitants from 4,420 municipalities), the second stratum (26,701–135,000 inhabitants from 951 municipalities), the third stratum (135,001–750,000 inhabitants from 171 municipalities), and the fourth stratum (>750,000 inhabitants from 23 municipalities). All residents aged 50 years or older in the selected households were eligible for the interview. An inverse sampling design was employed to mitigate nonresponse bias without enlarging the sample size. The final sample consisted of participants from 70 municipalities across the major regions of Brazil. Sample weights were derived to account for differential probabilities of selection and nonresponse. For further methodological details, including sampling procedures, refer to Lima-Costa et al 12 . The total study population data referred to 9,412 of both genders, who were included in the ELSI-Brazil database. Authorization to use the data was obtained through access registration on the study's official website: http://elsi.cpqrr.fiocruz.br/instrucoes-para-uso/.

Data collection was performed using an individual questionnaire and a household questionnaire that can be seen at https://elsi.cpqrr.fiocruz.br/questionario/. The dependent variable in our study was smoking (as reported: yes/no) according to the following question, "Do you currently smoke?" in the following context: "To finish this section, I will ask you some questions about smoking industrialized cigarettes, straw cigarettes or other tobacco products that are smoked, such as cigars, cigarillos, pipes, clove (or Bali) cigarettes, Indian cigarettes (or bidis) and hookah (or water pipes). Please do not respond about smokeless tobacco products such as snuff and chewing tobacco. Do not consider electronic cigarettes."

The independent variables were age (categorized in the median of the distribution, which was 62 years of age), skin color (categorized as white/non-white), marital status (with or without a partner), education (categorized in up to 8 years and more than 8 full years of study), remunerated work (yes/no), self-reported comorbidities in response to questions formulated as follows for each comorbidity included: "Has a doctor ever told you that you have arterial hypertension (high blood pressure)?" or "Has a doctor ever told you that you have diabetes (blood sugar)?" (has/does not have systemic arterial hypertension, hypercholesterolemia, asthma, chronic obstructive pulmonary disease, acute myocardial infarction, cardiac insufficiency, stroke, cancer, diabetes mellitus, depression, Alzheimer's disease, Parkinson's disease, repetitive strain injury), sleep quality (regular/good/very good or bad/very bad), and alcohol intake (no, once a month, or more than once a month).

Data were analyzed in the software SPSS Statistics for Windows, 18.0 (SPSS Inc., Chicago, IL, USA). Bivariate analyses between the dependent and independent variables were performed using the chi-square test to observe proportional homogeneity. All variables that were statistically significant with p<0.05, as well as those with p<0.20, were included in a multivariate model using Poisson regression with a robust estimator. These variables were ranked according to the stepwise forward adjustment technique, as proposed for hierarchical analysis of smoking prevalence and associated factors (Figure 1).

Figure 1 Proposal for a hierarchical analysis of smoking prevalence and associated factors in older adults aged 50 years and over.

ELSI-Brazil was approved by the Research Ethics Committee of the Centro de Pesquisas René Rachou da Fundação Oswaldo Cruz (protocol 34649814.3.0000.5091).

RESULTS

Data from 9,412 individuals aged 50 years or older from the ELSI-Brazil database was included. The average age was 63.5 years (SD=10.1), the median was 62 years, and 56.5% were female. The average level of education was 7 completed years of study (SD=8.7) and 16.4% were illiterate. The reported current smoking prevalence was 17.04% (95%CI 16.30–17.70) or 1,604 participants. Table 1 presents the bivariate analysis between sociodemographic variables, comorbidities, and smoking.

Table 1 Sociodemographic variables, comorbidities, and smoking (Brazilian adults aged 50 years and over).

Variables	Smoking	
n	%	PRc *	95%CI**	p-value	
First level—sociodemographic	
Gender	
	Male	843	20.6	1.04	1.03–1.05	<0.001	
	Female	761	14.4	1.00	
Skin color	
	White	564	15.7	1.00	1.01–1.03	0.012	
	Not white	972	17.7	1.02	
Age (median)	
	Over 62 years	566	12.7	1.00	1.04–1.06	<0.001	
	Up to 62 years	1.038	21.0	1.05	
Education	
	More than 8 years schooling completed	341	14.8	1.00	1.01–1.03	0.300	
	From 1 to 8 years schooling completed	965	17.5	1.02	0.042	
	Illiterate	284	18.6	1.03	1.01–1.04	<0.001	
Marital status	
	With partner	845	15.5	1.00	1.01–1.03	<0.001	
	No partner	759	19.1	1.02	
Remunerated activity	
	No	1.043	15.8	1.00	1.01–1.03	<0.001	
	Yes	561	19.9	1.02	
Second level—comorbidities	
Systemic arterial hypertension	
	No	910	20.8	1.00	0.95–0.97	<0.001	
	Yes	687	13.7	0.96	
Hypercholesterolemia	
	No	1.182	18.4	1.00	0.96–0.98	<0.001	
	Yes	403	13.9	0.97	
Asthma	
	No	1.514	17.0	1.00	0.98–1.02	0.587	
	Yes	85	17.9	1.01	
Chronic obstructive pulmonary disease	
	No	1.478	16.7	1.00	1.01–1.04	0.001	
	Yes	121	22.2	1.03	
Acute myocardial infarction	
	No	1.502	17.0	1.00	0.98–1.02	0.549	
	Yes	100	18.0	1.01	
Cardiac insufficiency	
	No	1.508	17.4	1.00	0.97–1.02	0.005	
	Yes	89	13.1	0.98	
Stroke	
	No	1.521	17.2	1.00	0.98–1.01	0.275	
	Yes	82	15.3	0.99	
Cancer	
	No	1.534	17.3	1.00	0.95–0.97	0.008	
	Yes	64	12.7	0.97	
Diabetes mellitus	
	No	1.391	17.8	1.00	0.96–0.99	<0.001	
	Yes	201	13.2	0.97	
Depression	
	No	1.263	16.5	1.00	1.01–1.03	0.002	
	Yes	335	19.6	1.02	
Alzheimer's disease	
	No	1.593	17.1	1.00	0.92–0.99	0.040	
	Yes	7	8.5	0.95	
Parkinson's disease	
	No	1.588	17.0	1.00	0.96–1.06	0.715	
	Yes	12	18.8	1.01	
Repetitive strain injury	
	No	487	19.9	1.00	0.97–0.99	<0.001	
	Yes	1.075	16.3	0.98	
Sleep quality	
	Regular/good/very good	1.246	16.3	1.00	1.01–1.03	<0.001	
	Bad/very bad	355	20.2	1.02	
Alcohol intake	
	No	939	13.6	1.00			
	Once a month	127	23.3	1.03	1.01–1.05	0.032	
	More than once a month	535	27.4	1.08	1.07–1.09	<0.001	
* PRc: Crude prevalence ratio.

** 95%CI: 95% confidence interval.

Table 2 displays the results of the multivariate analysis between sociodemographic variables, comorbidities, and current smoking in the final hierarchical model. The variables that were positively, statistically, and independently associated with a higher prevalence of current smoking were male gender (PR=1.03; 95%CI 1.02–1.04) (p<0.001), age up to 62 years of age (PR=1.04; 95%CI 1.03–1.05) (p<0.001), living without a partner (PR=1.04; 95%CI 1.03–1.05) (p<0.001), illiteracy (PR=1.04; 95%CI 1.02–1.06) (p<0.001), presence of chronic obstructive pulmonary disease (PR=1.03; 95%CI 1.01; 1.04) (p=0.011), depression (PR=1.03; 95%CI 1.01; 1.04) (p<0.001), bad or very bad sleep quality (PR=1.02; 95%CI 1.01–1.03) (p=0.001), and alcohol intake more than once a month (PR=1.08; 95%CI 1.05–1.09) (p<0.001). Variables associated with lower prevalence of current smoking in a statistically significant and independent way were systemic arterial hypertension (PR=0.97; 95%CI 0.96; 0.98) (p<0.001), hypercholesterolemia (PR=0.98; 95%CI 0.97–0.99) (p<0.001), diabetes mellitus (PR=0.98; 95%CI 0.97–0.99) (p=0.040), and repetitive strain injury (PR=0.98; 95%CI 0.96–0.99) (p=0.004).

Table 2 Sociodemographic variables, comorbidities, and current smoking in Brazilian older adults aged 50 years and over (Final model).

Variables	Current smoking	
PRa *	95%CI**	p-value	
First level—sociodemographic	
Gender	
	Female	1.00	1.02–1.04	<0.001	
	Male	1.03	
Age (median)	
	Over 62 years old	1.00	1.03–1.05	<0.001	
	Up to 62 years	1.04	
Marital status	
	With partner	1.00	1.03–1.05	<0.001	
	No partner	1.04	
Education	
	More than 8 schooling completed	1.00			
	From 1 to 8 schooling completed	1.01	0.99–1.03	0.081	
	Illiterate	1.04	1.02–1.06	<0.001	
Second level—self-reported comorbidities	
Systemic arterial hypertension	
	No	1.00	0.96–0.98	<0.001	
	Yes	0.97	
Hypercholesterolemia	
	No	1.00	0.97–0.99	<0.001	
	Yes	0.98	
Chronic obstructive pulmonary disease	
	No	1.00	1.01–1.05	0.011	
	Yes	1.03	
Cancer	
	No	1.00	0.97–1.00	0.061	
	Yes	0.98	
Diabetes mellitus	
	No	1.00	0.97–0.99	0.040	
	Yes	0.98	
Depression	
	No	1.00	1.01–1.04	<0.001	
	Yes	1.03	
Repetitive strain injury	
	No	1.00	0.96–0.99	0.004	
	Yes	0.98	
Sleep quality	
	Regular/good/very good	1.00	1.01–1.03	0.001	
	Bad/very bad	1.02	
Alcohol intake	
	No	1.00			
	Once a month	1.02	0.99–1.04	0.071	
	More than once a month	1.07	1.05–1.09	<0.001	
* PRa: adjusted prevalence ratio.

** 95%CI: 95% confidence interval.

DISCUSSION

The current smoking prevalence in Brazilian adults aged 50 years and older found in the present study was 17.04%. The PLATINO study (Proyecto Latinoamericano de Investigación en Obstrucción Pulmonar) in the city of São Paulo/SP in 2003 showed that around 24.0% of people aged 40 years or over were smokers, while 33.1% were ex-smokers 13 . In a recent study carried out in Japan, similar data were presented, indicating a prevalence of 13.8% of smoking among older adults 14 . The prevalence of current smoking in older adults in Brazil follows rates that are similar to those rates in other countries.

Regarding gender, a higher smoking prevalence was found among men, as shown in another Brazilian study 15 . This is in line with studies carried out with American older adults 15-17 . The epidemic history of tobacco shows that it has increased first among males and later among females 18 .

In our study, age was dichotomized in the median of the distribution with a value of 62 years, observing a higher prevalence of smoking in those individuals aged up to 62 years. A previous study carried out in Brazil presents similar data with a lower prevalence in older adults. In this same study, the results show that the lower the level of education, the greater the prevalence of smoking. The higher the level of education, the greater the access to information on the risks of tobacco use; perhaps this is the condition behind the lower smoking practice, as it is believed that it is through knowledge and education that people become aware and, therefore, start to abandon practices that increase the risk of diseases and adopt others that generate health.

This study demonstrated that relationships can positively influence healthy habits. In addition, another study presents results showing that marriage is a protective factor for quitting smoking, thus reducing smoking rates 19 .

In addition, a positive association was observed between smoking and alcohol consumption. A study in which the combined consumption of alcohol and tobacco was adopted as the dependent variable showed that the increased prevalence of both substances’ consumption converged in the bivariate analysis when correlated with other independent variables, such as education 20 . The association between both substances may be due to the social influence that smoking and alcohol have in common.

Regarding self-reported comorbidities, a higher prevalence of smoking was observed in individuals with some chronic diseases. However, it is important to highlight that self-reporting of chronic diseases is related to the possibility of underdiagnosis or even overdiagnosis. A study carried out in Canada showed that female smokers were more prone to the development of chronic diseases, chronic obstructive pulmonary disease, and lung cancer 19 . Male smokers are more likely to develop comorbidities, including chronic obstructive pulmonary disease and lung cancer 21 . A study conducted in the United States showed that smokers were more likely to develop depression 22 .

A few other diseases were associated with a reduced rate of smoking, such as hypercholesterolemia, diabetes mellitus, and repetitive strain injury. This could be due to the concern with comorbidity and the pursuit of a better quality of life. On the contrary, bad or very poor sleep quality was associated with higher smoking rates. Smoking is associated with the development of sleep disorders 23 and an increased insomnia incidence 24 .

The results of the present study should be interpreted with caution, and the objective of the study was to estimate the current prevalence of smoking some years ago. And this scenario may have changed. Furthermore, the associations found may be the result of reverse causality, since, for example, a person who smoked all his/her life and was diagnosed with hypertension may probably stop smoking. In addition, the results of our study indicate that longitudinal studies are crucial to establishing the cause of some chronic diseases that are associated with a decrease and others with an increase in the prevalence of smoking in adults over 50 years of age. Another limitation concerns gathering information from individuals who decline to participate, making it challenging to compare them with participants and assess selection bias. However, ELSI-Brazil employed an inverse sampling design to address nonresponse bias without increasing the sample size.

It can be concluded that the prevalence of current smoking among older adults aged 50 years and older in Brazil was 17.04%. Factors associated with increased smoking prevalence in this age group included male gender, living without a partner, lower education level, the presence of chronic obstructive pulmonary disease, depression, poor quality of sleep, and alcohol intake. Participants’ conditions associated with the decrease in smoking prevalence were systemic arterial hypertension, hypercholesterolemia, and repetitive strain injury.

Funding: ELSI-Brazil was supported by the Brazilian Ministry of Health: DECIT/SCTIE – Department of Science and Technology from the Secretariat of Science, Technology and Strategic Inputs (Grants: 404965/2012-1 and TED 28/2017) and COPID/DECIV/SAPS – Health Coordination of the Older Person in Primary Care, Department of Life Course from the Secretariat of Primary Health Care (Grants: 20836, 22566, 23700, 25560, 25552, and 27510).
==== Refs
REFERENCES

1 Ministério da Saúde do Brasil Diretrizes para o cuidado das pessoas idosas no SUS: proposta de modelo de atenção integral 2014 cited on 2023 Mar 25 Available from: https://bvsms.saude.gov.br/bvs/publicacoes/diretrizes_cuidado_pessoa_idosa_sus.pdf
2 Kondo T Nakano Y Adachi S Murohara T Effects of tobacco smoking on cardiovascular disease Circ J 2019 83 10 1980 1985 10.1253/circj.CJ-19-0323 31462607
3 Yoshida K Gowers KHC Lee-Six H Chandrasekharan DP Coorens T Maughan EF Tobacco smoking and somatic mutations in human bronchial epithelium Nature 2020 578 7794 266 272 10.1038/s41586-020-1961-1 31996850
4 Serrano-Alarcón M Kunst AE Bosdriesz JR Perelman J Tobacco control policies and smoking among older adults: a longitudinal analysis of 10 European countries Addiction 2019 114 6 1076 1085 10.1111/add.14577 30868688
5 Pichon-Riviere A Alcaraz A Palacios A Rodríguez B Reynales-Shigematsu LM Pinto M The health and economic burden of smoking in 12 Latin American countries and the potential effect of increasing tobacco taxes: an economic modelling study Lancet Glob Health 2020 8 10 e1282 e1294 10.1016/S2214-109X(20)30311-9 32971051
6 Instituto Nacional do Câncer Dados e números da prevalência do tabagismo 2022 cited on 2023 Mar 25 Available from: https://www.inca.gov.br/observatorio-da-politica-nacional-de-controle-do-tabaco/dados-e-numeros-prevalencia-tabagismo
7 Ministério da Saúde do Brasil Pesquisa especial de tabagismo PETab 2008 cited on 2023 Mar 25 https://bvsms.saude.gov.br/bvs/publicacoes/pesquisa_especial_tabagismo_petab.pdf
8 Instituto Brasileiro de Geografia e Estatística (IBGE) Pesquisa Nacional de Saúde – PNS 2013 cited on 2023 Mar 30 https://sidra.ibge.gov.br/pesquisa/pns
9 Fundação Oswaldo Cruz Relatório da OMS sobre tabaco destaca Brasil 2019 cited on 2023 Mar 30 Available from: https://portal.fiocruz.br/noticia/relatorio-da-oms-sobre-tabaco-destaca-brasil
10 Ministério da Saúde do Brasil Secretaria de Vigilância em Saúde e Ambiente. Vigitel Brasil 2006-2023: tabagismo e consumo abusivo de álcool: vigilância de fatores de risco e proteção para doenças crônicas por inquérito telefônico: estimativas sobre frequência e distribuição sociodemográfica de fatores de risco e proteção para doenças crônicas nas capitais dos 26 estados brasileiros e no Distrito Federal entre 2006 e 2023 Ministério da Saúde do Brasil 2023
11 ELSI Estudo Longitudinal da Saúde Idosos Brasileiros. O que é o ELSI-Brasil 2023 cited on 2022 Feb 20 Available from: http://elsi.cpqrr.fiocruz.br/a-pesquisa/o-que-e-o-elsi-brasil/
12 Lima-Costa MF Andrade FB Souza PRB Neri AL Duarte YAO Castro-Costa E The Brazilian longitudinal study of aging (ELSI-Brazil): objectives and design Am J Epidemiol 2018 187 7 1345 1353 10.1093/aje/kwx387 29394304
13 Menezes AM Jardim JR Pérez-Padilla R Camelier A Rosa F Nascimento O Prevalence of chronic obstructive pulmonary disease and associated factors: the PLATINO Study in São Paulo Brazil. Cad Saude Publica. 2005 21 5 1565 1573 10.1590/s0102-311×2005000500030 16158163
14 Lu Y Sugawara Y Zhang S Tomata Y Tsuji I Smoking cessation and incident dementia in elderly Japanese: the Ohsaki Cohort 2006 Study Eur J Epidemiol 2020 35 9 851 860 10.1007/s10654-020-00612-9 32060675
15 Jamal A Phillips E Gentzke AS Homa DM Babb SD King BA Current cigarette smoking among adults - United States, 2016 MMWR Morb Mortal Wkly Rep 2018 67 2 53 59 10.15585/mmwr.mm6702a1 29346338
16 Malta DC Gomes CS Andrade FMD Prates EJS Alves FTA Oliveira PPV Tobacco use, cessation, secondhand smoke and exposure to media about tobacco in Brazil: results of the National Health Survey 2013 and 2019 Rev Bras Epidemiol 2021 24 suppl 2 e210006 10.1590/1980-549720210006.supl.2
17 Restifo D Zhao C Kamel H Iadecola C Parikh NS Impact of cigarette smoking and its interaction with hypertension and diabetes on cognitive function in older Americans J Alzheimers Dis 2022 90 4 1705 1712 10.3233/JAD-220647 36314206
18 Carvalho Souza M Giunta DH Szklo AS Almeida LM Szklo M The tobacco epidemic curve in Brazil: where are we going? Cancer Epidemiol 2020 67 101736 101736 10.1016/j.canep.2020.101736 32521489
19 Broms U Silventoinen K Lahelma E Koskenvuo M Kaprio J Smoking cessation by socioeconomic status and marital status: the contribution of smoking behavior and family background Nicotine Tob Res 2004 6 3 447 455 10.1080/14622200410001696637 15203778
20 Alkan Ö Abar H Gençer Ö Analysis of factors affecting alcohol and tobacco concurrent use by bivariate probit model in Turkey Environ Sci Pollut Res Int 2021 28 23 30168 30175 10.1007/s11356-021-12849-2 33586099
21 Ng R Sutradhar R Yao Z Wodchis WP Rosella LC Smoking, drinking, diet and physical activity-modifiable lifestyle risk factors and their associations with age to first chronic disease Int J Epidemiol 2020 49 1 113 130 10.1093/ije/dyz078 31329872
22 Wu Z Yue Q Zhao Z Wen J Tang L Zhong Z A cross-sectional study of smoking and depression among US adults: NHANES (2005-2018) Front Public Health 2023 11 1081706 1081706 10.3389/fpubh.2023.1081706 36794066
23 Amiri S Behnezhad S Smoking and risk of sleep-related issues: a systematic review and meta-analysis of prospective studies Can J Public Health 2020 111 5 775 786 10.17269/s41997-020-00308-3 32185746
24 Hu N Wang C Liao Y Dai Q Cao S Smoking and incidence of insomnia: a systematic review and meta-analysis of cohort studies Public Health 2021 198 324 331 10.1016/j.puhe.2021.07.012 34507139
