|Year : 2017 | Volume
| Issue : 1 | Page : 59-64
Epidemiology of exposure to secondhand smoke from cigarettes among innocent never smoked adult nigerians in a resource-poor environment of a primary care clinic in Southeastern Nigeria
Gabriel Uche Pascal Iloh1, Agwu Nkwa Amadi2, Okechukwu Kalu Iro3
1 Department of Family Medicine, Federal Medical Centre, Umuahia, Abia State; Department of Public Health, Federal University of Technology, Owerri, Imo State, Nigeria
2 Department of Public Health, Federal University of Technology, Owerri, Imo State, Nigeria
3 Department of Environmental Health Sciences, Faculty of Basic Medical Sciences, College of Medicine and Health Sciences, Abia State University, Okigwe, Nigeria
|Date of Web Publication||16-Jun-2017|
Gabriel Uche Pascal Iloh
Department of Family Medicine, Federal Medical Centre, Umuahia, Abia State
Source of Support: None, Conflict of Interest: None
Background: Exposure to secondhand smoke from cigarettes is a public health hazard that is increasing globally and emerging in resource-poor nations where the health effects of secondhand smoke are less publicized in biomedical literatures, electronic and print media. As the global prevalence of cigarette smoking increases so does the health hazards and harm associated with secondhand smoke increases with implication for family and community health. Aim: The study was aimed at describing the epidemiology of exposure to secondhand smoke from cigarettes among innocent never smoked adult Nigerians in a primary care clinic of a tertiary hospital in Nigeria. Materials and Methods: A cross-sectional descriptive hospital-based study was carried out on 500 adult Nigerian patients in a primary care clinic in Nigeria. Data were collected using pretested, structured, and interviewer-administered questionnaire containing information on relevant epidemiological variables. Exposure to secondhand smoke was defined as exposure to cigarette smoke in a never smoked adult in the previous 1 year. Results: The prevalence of exposure to secondhand smoke was 45.0%. Exposures occur predominantly among males (56.4%), middle-aged adults (44.0%), outside home environment (72.0), during the daytime (63.6%), and dry season (58.7%). The persons involved in the smoking were principally friends and passersby (65.8%). Exposure to secondhand smoke was associated with age (middle-aged adults) (P = 0.036) and male gender (P = 0.02). Conclusion: This study has demonstrated the variable epidemiology of exposure to secondhand smoke. Tackling relevant epidemiological factors that predispose to exposure to secondhand smoke through programs and policies will facilitate appropriate public health action to safeguard the health of never smoked individuals.
Keywords: Adult Nigerians, cigarettes, epidemiology, never smoked, primary care, secondhand smoke
|How to cite this article:|
Iloh GU, Amadi AN, Iro OK. Epidemiology of exposure to secondhand smoke from cigarettes among innocent never smoked adult nigerians in a resource-poor environment of a primary care clinic in Southeastern Nigeria. Arch Med Health Sci 2017;5:59-64
|How to cite this URL:|
Iloh GU, Amadi AN, Iro OK. Epidemiology of exposure to secondhand smoke from cigarettes among innocent never smoked adult nigerians in a resource-poor environment of a primary care clinic in Southeastern Nigeria. Arch Med Health Sci [serial online] 2017 [cited 2022 Nov 30];5:59-64. Available from: https://www.amhsjournal.org/text.asp?2017/5/1/59/208188
| Introduction|| |
Cigarette smoking whether directly or indirectly is a growing public health problem worldwide, especially in developing countries like Nigeria undergoing rapid socioeconomic and technological development characterized by a transition from traditional to Western lifestyles.,,, As the global prevalence of smoking increases so does the health hazards and harm associated with exposure to secondhand smoke increases with implications for the family and community health in Nigeria  and other parts of the world such as India, Canada, Spain, and New Zealand.
Globally, more than a third of adult world population is exposed to secondhand smoke, and secondhand smoke was responsible for 600,000 deaths annually contributing to 1% of global burden of diseases. The prevalence of exposure to secondhand smoke from cigarettes has been reported across different global populations: 83% was reported among students in California, 37% in Cambodia, 48.3% in China, 68% in Seoul, Korea, 69.7% in Spain, and 54.4% in Egypt. Among Nigerian Africans, 38.8% was reported among adult population in Ilorin, Southwest Nigeria  and Enugu, Southeast Nigeria  and 42.6% was reported among students of Niger Delta University, South-South Nigeria.
Research studies have shown that there is no safe level of exposure to secondhand smoke and that secondhand smoke contains higher concentrations and more harmful chemicals than the first-hand smoke inhaled by the smokers.,, The more secondhand smoke you inhale, the higher the levels of the toxic chemicals in your body and the likelihood of developing smoking-related health problems.,, Exposure to secondhand smoke is widely recognized as a significant cause of short-term and long-term health effects with particular concern for the health of vulnerable groups, particularly children.,,, There is also evidence linking exposure to secondhand smoke with various health conditions such as lung cancer, cardiovascular diseases, respiratory conditions, and obstetric complications.,,,
In various global populations, exposure to secondhand smoke can occur at home, workplaces, cars, and public places such as parks, restaurants, and wedding ceremonies.,,, However, in a Global Adult Tobacco Survey (GATS) done in Nigeria, it was estimated that 29.3% adult Nigerians were exposed to secondhand smoke in restaurants, 17.3% in workplaces, 9.4% in public transport, 6.6% at home, and 5.3% in health-care facilities. In India, an analysis of GATS report 2009 among women showed that 50.4% were exposed at home, 21.7% at work, and 32.6% elsewhere such as restaurants, transport, and health facility; among the Indian population aged 13–15 years, 21.9% and 36.6% were exposed to secondhand smoke at home and in public places, respectively. The goal of comprehensive tobacco control program in the MPOWER report , includes protection of the people from tobacco smoke, whereas Article 8 of the WHO Framework Convention on Tobacco Control “Parties recognize that scientific evidence has unequivocally established that exposure to tobacco smoke causes death, disease, and disability. Each party shall adopt and implement measures, providing for protection from exposure to tobacco smoke in indoor workplaces, public transport, indoor public places and as appropriate, other public places.”,
In Nigeria, exposure to secondhand smoke is quite common in public places and patients that present to the primary care clinic are not protected advertently or inadvertently from secondhand smoke from cigarettes. However, there is no study on exposure to secondhand smoke in primary care settings in the subregion. The primary care patients are population at risk of exposure to the health effects of secondhand smoking and are likely to be unaware of the health effects of exposure to secondhand smoke. It is based on this premise that the authors were motivated to study the epidemiology of exposure to secondhand smoke from cigarettes among innocent never smoked adult Nigerians in a primary care clinic of a tertiary hospital in Nigeria.
| Materials and Methods|| |
This was a cross-sectional descriptive study carried out on 500 adult patients from August 2016 to September 2016 at the Department of Family Medicine of the Federal Medical Centre (FMC), Umuahia, a tertiary hospital in Abia State, Southeast Nigeria.
Umuahia is the capital of Abia state, Nigeria. Abia State is endowed with abundant mineral and agricultural resources with supply of professional, skilled, semi-skilled, and unskilled workforce. Economic and social activities are low compared to industrial and commercial cities such as Onitsha, Port Harcourt, and Lagos in Nigeria. Until recently, the capital city and its environ have witnessed an upsurge in the number of banks, hotels, schools, markets, industries, junk food restaurants in addition to the changing dietary, and social lifestyles.
The study was conducted at the Department of Family Medline of FMC, Umuahia, Nigeria. The Department of Family Medicine of the hospital serves as a primary care clinic within the setting of the tertiary hospital. Patients who need primary care are managed and followed up in the clinic, whereas those who need other specialists care are referred to the respective core specialist clinics for further management.
The inclusion criteria were patients aged 18 years and above and those who had never smoked cigarette in their lifetime. The exclusion criteria were critically ill patients, ex-smokers, and current smokers.
Sample size was estimated using the formula for calculating minimum sample size for descriptive studies  when the population is equal or more than 10,000; N = Z2pq/d2 where N = minimum sample size, Z = standard normal deviation usually set at 1.96 which corresponds to 95% confidence interval, and P = proportion of the population estimated to have a particular characteristic. Due to the absence of similar study on exposure to secondhand smoke among primary care patients in Nigeria, the authors assumed that 50% of the adult patients  would be exposed to secondhand smoke from cigarettes at 95% confidence level and 5% margin of error. This assumption was likely to maximize the estimated variance and provided a sample size that was precisely representative for the study population. This gave a sample size estimate of 384; thus q = 1.0 – P = 1.0 − 0.5 = 0.5, d = degree of accuracy set at 0.05. Hence, N = (1.96) 2 × 0.5 × 0.5/(0.05) 2. Therefore, N = 384. A sample size of 500 patients was used for the study to improve the precision of the study.
The sampling technique involved consecutive selection of every adult patient who registered to see the clinicians on each consulting day during the study period and who met the inclusion criteria until the sample size of 500 was achieved.
The study tool was designed by the researchers from GATS Global Tobacco Surveillance System, the National Human Activity Pattern Survey, and robust review of literature on previous studies on exposure to secondhand smoke.,,,,,,,,,,,,,,,,
The questionnaire tool consisted of sections on sociodemographic variables and other relevant epidemiological variables. The questionnaire was researcher administered to avoid incomplete information on the study tool. The questionnaire tool was also pretested for reliability and operational feasibility using ten never smoked patients. The pretesting was done to find out how the questions would interact with the respondents and ensure there were no ambiguities. However, no change was necessary after the pretesting as the questions were interpreted with the same meaning as intended.
Operationally, adult patients were classified based on their age into young adults who were aged 18–39 years, middle-aged adults (40–59 years), and elderly (60 years and more). The seasons of exposure were categorized into two: Rainy and dry or harmattan seasons based on the Nigerian seasonal expression. Dry or harmattan season is the period from November to March, whereas rainy season refers to the period from April to October. The time of exposure was divided into two based: Daytime was defined inclusively as the time from 6.00 am to 6.00 pm Nigerian time, whereas nighttime refers exclusively to the time from 6.00 pm to 6.00 am Nigerian time. Secondhand smoke referred to involuntary inhalation of smoke from burning cigarettes generated by another person. Exposure to secondhand smoke referred passive smoking or breathing in of smokers smoke. Exposure to secondhand smoke was defined as exposure to cigarette smoke in a never smoked adult in the previous 1 year.
Ethical certification was obtained from Health Research and Ethics Committee of the hospital. Informed consent was also obtained from the respondents included in the study.
The data generated were analyzed using software Statistical Package for Social Sciences software version 21 (IBM SPSS, New York, USA). Categorical variables were described by frequencies and percentages. Bivariate analysis involving Chi-square test was used to test for significance of association between categorical variables. The level of significance was set at P < 0.05.
| Results|| |
Of the 500 never smoked subjects who participated in the study, 225 were exposed to secondhand smoke giving a prevalence of 45.0%. Two hundred and seventy-five (55.0%) were not exposed to secondhand smoke from cigarettes [Table 1].
|Table 1: Prevalence of exposure to secondhand smoke among the study participants (n=500)|
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Of the 225 participants who were exposed to secondhand smoke from cigarettes, 99 (44.0%) were aged middle-aged adults (40–59 years), followed by young adults (18–39 years) (32.4%) and elderly age group (≥60 years) (23.6%). Similarly, of the 225 participants who were exposed to secondhand smoke from cigarettes, 127 (56.4%) were males while 98 (43.6%) were females [Table 2].
|Table 2: Age and sex distribution of the participants who were exposed to secondhand smoke (n=225)|
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One hundred and sixty-two (72.0%) participants who were exposed to secondhand smoke occurred outside the home environment; 36 (16.0%) occurred both at home and outside home environment, whereas 27 (12.0%) occurred at home; 143 (63.6%) participants who were exposed to secondhand smoke occurred during the daytime (6 am–6 pm inclusive), whereas 82 (36.4%) happened during the nighttime (6 pm–6 am exclusive). One hundred and thirty-two (58.7%) of the exposure to secondhand smoke occurred during the dry (harmattan) season, whereas 93 (41.3%) happened during the rainy season [Table 3].
|Table 3: Distribution of exposure to secondhand smoke by place, time, and season of occurrence (n=225)|
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On the distribution of the exposure based on the person involved in first-hand smoking, 206 (65.8%) were by passersby and friends. The perpetrators in 83 (26.5%) of the cases of exposure to secondhand smoke were by co-workers and co-students, whereas in 24 (7.7%) participants, the culprits were household family members [Table 4].
|Table 4: Distribution of exposure to secondhand smoke by person involved in the smoking ( first-hand smoker)*|
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Bivariate analysis of the demographic variables as related to exposure to secondhand smoke showed that age (40–59 years) (χ2 = 8.01; P = 0.036) and gender (male) (χ2 = 15.62; P = 0.02) were statistically significant, whereas other demographic variables were not statistically significant [Table 5].
|Table 5: Association between exposure to secondhand smoke and sociodemographic variables|
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| Discussion|| |
The prevalence of exposure to secondhand smoke among the study participants was 45.0%. This is higher than the prevalence of 38.8% reported in a cross-section of adult Nigerians from Enugu, Southeast Nigeria  and Ilorin, Western Nigeria; 37% reported in the Kingdom of Cambodia, Southeast Asia  but lower than the results of 83% from California, the Western United States of America, 54.4% in Egypt, 48.3% in People's Republic of China, 68% in Seoul, Korea, and 69.7% in Spain. The lower prevalence of exposure to secondhand smoke in this study compared to previous studies from Europe, the United States of America, and Asia could be attributed to the higher prevalence of active cigarette smoking in Europe, the United States of America, and Asia when compared with Nigeria, Africa. Although the components of cigarette vary according to the chemicals added to the tobacco during production process, there is no safe level of exposure to secondhand smoke worldwide. The only way to protect innocent never smoked individuals is for the smokers to quit smoking. However, never smoked persons should be advised to avoid public places where total separation of smoking area from nonsmoking space is not enforced. In Nigeria, there is promotion of personal behavioral change to active cigarette smoking through antismoking warnings of the dangers of cigarette smoking on the cigarette packets. In the previous past, the warning message was “smoking is dangerous to health,” but at present, the antismoking message is “smokers are liable to die young” as recommended by Federal Ministry of Health, Nigeria. Multilevel tobacco-control strategies should, therefore, include exposures to secondhand smoke to protect innocent never smoked individuals. Warning on cigarette packets should also include information on deleterious effects of secondhand smoke on health.
This study has shown that middle-aged never smoked adults were more exposed to secondhand smoke from cigarettes compared to other age groups. This could be a reflection of the age groups that access care at the primary clinic of the hospital. Although the use of cigarettes decreases in adults with increasing age, the risk of exposure is higher among the middle-aged adults when compared with the elderly age group. The middle-aged adults are more likely to be working-class, socially active, and more likely to be found in public places where cigarettes are smoked and other social drinks such as alcohol are consumed. Increasing socialization increases the risk of exposure to secondhand smoke from cigarettes. There is, therefore, need to ensure smoke-free environments in the subregion to guarantee public health benefit of environmental justice and safety which offers universal protection to everyone irrespective of age.
One hundred and twenty-seven males (56.4%) were more exposed to secondhand smoke when compared with 98 (43.6%) females. This finding is in consonance with global epidemiological pattern, especially in developing countries, and research studies which have shown the preponderance of males as victims of exposure to secondhand smoke from cigarettes., The higher rate of exposure in males could also be a reflection of higher prevalence of smoking among the male folk. However, in the past decade, the number of females who smoke is alarmingly increasing globally, and the gap is narrowing. More so, sociocultural factors are contributory among Nigerian Africans. In Nigeria, the society frowns at females smoking cigarettes, and this could limit their presence in the environment where exposure to secondhand smoke occurred. In addition, males in Nigeria are more likely to socialize than females, have male friends who smoke cigarettes, and are more likely to be in public places where exposure to secondhand smoke is highest.
Exposure to secondhand smoke occurred predominantly during the daytime (6 am–6 pm inclusive). This could be due to the fact that increasing socialization which occurs preferentially during the daytime in the study area increases the risk of exposure to secondhand smoke from cigarettes. The higher frequency of exposure to secondhand smoke from cigarettes during the day time in this study also corresponded with the period of maximum outdoor activities in the study area which occurred predominantly during the daytime.
Exposure to secondhand smoke occurred mostly during the dry season, particularly during the month of December (Christmas month). This could be a reflection of wider social interactions and increased frequency of sociocultural functions (festivities and ceremonies), and outdoor activities that characterized the dry season. Of great concern in the study area is that smoking is a common way of socializing among the youths and middle-aged adults as well as ameliorating the effects of cold ambience associated with harmattan breeze. In addition, socioculturally, packets of cigarettes are one of the prerequisite items listed for the youths during marriage rites, chieftaincy titles, and burial ceremonies. These festivities and ceremonies occurred preeminently during the month of December.
One hundred and sixty-two of the respondents had exposure outside the home environment. This finding is similar to reports from other parts of Nigeria , but differs from reports from India, Norway, and the USA , where homes were the most common site of exposure to secondhand smoke due to the displacement of smokers from the public places by enabling regulations and laws. The findings of this study are expected since public places are usual places that allow for social interactions between smoking and nonsmoking adults in Nigeria. There is a need to educate the proprietors of public outlets on the harmful effects of secondhand smoke. Although some business premises might be afraid to ban smoking or sell of cigarettes, there is no evidence to show that designating premises smoke-free will deter customers. There is, therefore, increasing public support for restriction to be placed on smoking in the public places. The only effective way to protect the public from secondhand smoke is to make public places completely smoke-free through legislative enforcement and regulations.
The exposure to secondhand smoke from cigarettes was significantly associated with age and gender with the male gender and middle-aged being predominantly affected. The factors responsible for variability in the exposure to secondhand smoke between this study and other studies ,,,,, could be due to the epidemiological characteristics of the study population. Generally, epidemiological reports from Nigeria ,, have shown that male gender and middle-age adults as a stronger risk factor for exposure to secondhand smoke from cigarettes. This could be a reflection of the environment of smoking which is predominantly in public places in Nigeria with poor public health laws and weak legislative enforcement where such laws on smoking in public places are enacted and extant., Although there are no laws prohibiting a smoker in Nigeria from smoking in his or her home, Nigerians do not have to wait for the government to enact laws on prohibition of cigarette smoking at home. Making smokers home free of secondhand smoke is one of the most important things for the health of the family, especially the vulnerable groups such as young children whose growing bodies are particularly very sensitive to toxic chemicals from secondhand smoke from cigarettes. This, therefore, calls for smoke-free policies and enabling laws to cover home, workplaces, and other public places to safeguard the health of never smoked innocent individuals.
Limitations of the study
The limitations of this study are recognized by the researchers. First and foremost, the study was hospital-based. Hence, the results of this study may not be general conclusions regarding respondents in the community. Second, the sampled population was drawn from hospital attendees in the primary care clinic of the hospital. Thus, extrapolation of the results of this study to the entire patients in the hospital should be done with caution because the findings may not be a true representation of what may be obtained in the other clinics of the hospital. Third, this study was dependent on self-reported sociobehavioral exposure factors, and this could have led to recall bias and social desirable responses. Fourth, the assessment of the exposure to secondhand smoke was not quantitative. Although secondhand smoke can be assessed directly by airborne concentration or biomarker estimation, this study employed indirect questionnaire method to study the epidemiology of exposure to secondhand smoke. This method has been used in previous studies and can provide data on the magnitude of secondhand smoke in the study area for consultative and comparative purposes. Finally, this study was not an all-inclusive study on epidemiology of exposure to secondhand smoke but on some selected epidemiological variables.
| Conclusion|| |
This study has demonstrated the variable epidemiology of exposure to secondhand smoke. Exposures occur predominantly among males, middle-aged adults, outside home environment, during the daytime and dry season. The persons involved in the smoking were principally friends and passersby, and exposure to secondhand smoke was associated with age (middle-aged adults) and male gender.
Tackling relevant epidemiological factors that predispose to exposure to secondhand smoke through programs, laws, and policies will facilitate appropriate public health action to safeguard the health of never smoked individuals.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]