Introduction
Health studies have often highlighted a relationship between asthma and smoking (Lee, Forey, & Coombs, 2012). Indeed, most researchers claim that most people who have asthma and smoke, at the same time are in double jeopardy because, as if tobacco smoke is not bad enough, their asthmatic condition could be triggered by irritants contained in the tobacco smoke, thereby leading to allergic inflammation of the bronchial tubes (Dutra, Williams, Gupta, Kawachi, & Okechukwu, 2014).
This condition could lead to excessive mucus production, chronic cough and phlegm (Lee et al., 2012). For many asthmatic patients, tobacco irritants not only manifest in the aforementioned symptoms, but also make breathing difficult. This is in addition to the shortness of breath that they suffer periodically and the typical respiratory issues caused by cigarette smoking, such as emphysema, which they may suffer experience as well (Gilreath, Chaix, King, Matthews, & Flisher, 2012).
The relationship between asthma and smoking explains why many adults who develop asthma past their 50th birthdays often have a history of smoking tobacco (Dutra et al., 2014). Our topic of study is centered on exploring the relationship between asthma incidence and smoking among adult African Immigrants in California.
We need to conduct this study because African immigrants are a relatively understudied group. Furthermore, they are mostly underinsured than the general American population and experience significant variations, in terms of education and income outcomes, relative to other ethnic groups as well (Dutra et al., 2014). Indeed, because of their low socioeconomic status, studies have shown that they often experience inadequate medical care, which is often characterized by improper diagnosis of medical conditions (Dutra et al., 2014; Gilreath et al., 2012).
This problem often creates an inadequate recognition of asthma severity and the under-prescription of controller medications by health care service providers. Besides poor socioeconomic conditions, African immigrants also suffer from other risk factors such as environmental exposures (because of the difficult working conditions they are often subject to) and respiratory tract infections that are often associated with low-income living (Dutra et al., 2014).
This study would have a positive impact on social change because it would help to reduce the impact of asthma incidences within the target population. Such an outcome would come from understanding the relationship between smoking and asthma. For example, if we establish a positive relationship between the two variables, we could reduce the impact of smoking and minimize the impact of asthma at the same time. Similarly, if we establish no significant relationship between smoking and asthma within the target population, we could focus on other areas of health intervention to reduce the incidence of asthma among African immigrants in California. This study could also help to promote positive social change by informing health policy decisions regarding smoking and asthma management in the state of California.
Theoretical/Conceptual Framework
The socio-ecological theory will be the main conceptual framework for this study. Introduced in the 1970s by sociologists coming from the Chicago School, and revised by Bronfenbrenne throughout the 1970s and 1980s, this theory has been used to merge behavioral issues and anthropology issues in health studies (Moore, de Silva-Sanigorski, & Moore, 2013). The theory has five nested levels of interlocking behavioral and anthropology factors – interpersonal, organization, community, individual, and policy enabling environments. The diagram below shows how these levels interact.
A key contribution of this theory to different fields of health and psychology is the understanding that the true comprehension of human growth should occur through a complete understanding of the ecological system, which supports or influences their behaviors (Yakob & Ncama, 2016).
The rationale for using this theoretical framework in this study stems from its ability to show different levels of personal and environmental factors affecting human behaviors and health outcomes. It does so by considering the complex interplay between the five layers of personal and environmental factors mentioned. We also justify its application in this study because it has been used to successfully prevent domestic violence, child abuse, and promote community health (among other contributions in public health) (Gilioli, Caroli, Tikubet, Herren, & Baumgärtner, 2014). Its success in community health promotion is the main motivator for applying it in this study.
This theoretical framework is relevant to our research issue because it would help us to uncover the personal and environmental factors that could explain an association between asthma and smoking among African immigrants (Onono et al., 2015). Concisely, smoking is a personal issue that is often associated with environmental factors, such as culture, peer influence, stress and such like factors. Similarly, asthma is a personal and environmental issue because it could be triggered or exacerbated by biological or environmental factors. Immigration also changes the environmental context that could affect human health outcomes.
In this regard, this fact could help to explain the environmental issues of African immigrants in California that could affect their health status. In this regard, this theory is useful to our research study because it provides a holistic perspective of our research issue. More specifically, it incorporates all our research variables because smoking is a sociological (behavioral) issue, while the health issues (asthma) affecting African immigrants living in California could be moderated by environmental factors.
Approach for the Study
The quantitative approach is applicable to this research because our main source of research information – the CHIS dataset and codebook is quantitative in nature. There are different types of research approaches in quantitative studies. The main ones include descriptive research, correlation research, quasi-experimental research, and experimental research (Jacobsen, 2016). The correlation approach is the main approach to this study because it focuses on determining the existence and extent of a relationship between two or more variables.
It aligns with our research topic because we also strive to investigate the association between asthma incidence and smoking among adult African immigrants in California. Thus, the justification for using the correlation approach rests in the fact that it seeks to find out and interpret relationships between different variables (Guest, 2014).
As highlighted in this paper, our research topic is centered on investigating the association between asthma incidence and smoking among adult African immigrants in California. The research variables for this study include asthma, as the dependent variable, smoking as the independent variable, and age, sex, years since immigration, marital status, alcohol use, education level, income level, and employment status as mediating variables, or covariates.
Definitions
Asthma (Dependent variable)
A respiratory condition characterized by the presence of spasms in the nasal cavity. It often causes difficulty in breathing and an inflammation of the lungs. Some common symptoms include wheezing, coughing, and shortness of breath.
Smoking (Independent variable)
The inhalation of tobacco smoke through the burning of cigarettes. Smoking is often a behavioral issue characterized as a recreational drug habit.
Socio-ecological Model (SEM)
A model for understanding the interaction between personal and ecological effects of human behavior. The model is often used to identify behavioral and organizational leverage points that could be used to improve human health outcomes.
California Health Interview Survey (CHIS)
One of the largest health surveys in America that provides population-based, standardized health-related data. The data is often obtained from 58 counties within America and is collected using telephone surveys.
Assumptions
According to Whaley (2014), assumptions are things that are believed to be true, but cannot be verified by the researcher. One key assumption in this study is that the findings from the California Health Interview Survey are credible and reliable. In other words, we believe that this information is free from errors because the dataset forms the bedrock of our research findings. We also assume that the findings obtained in this study are representative of all African immigrants, regardless of their social or cultural affiliations.
The assumptions outlined in this review are necessary in the processing of the research findings because, without them, it would be difficult to guarantee the relevance of the research study. Furthermore, by stating these assumptions, it is easier for consumers of the research findings to understand the extent of reliability associated with the information explained, as well as the extent to which they should regard the information as true.
Scope and Delimitations
This research seeks to explore the relationship between smoking and asthma among adult African immigrants in California. Specific aspects of the research that are addressed in the research problem include smoking habits, asthma incidence, and African immigrants as the main target group. We chose this research focus because it has a high internal validity since the California Health Interview Survey, which is our main source of data, investigated different health outcomes/issues. Stated differently, it did not only focus on our variables (smoking and asthma were only two variables among many).
Therefore, the likelihood that the respondents thought the survey was only investigating the relationship between smoking and asthma is low. Hegde (2015) considers this feature as a strong predictor of internal validity and calls it the “double-blind technique,” where the respondents and the researcher both do not understand what the investigative process represents. One boundary of the study is the inclusion of only African immigrant groups. We also only included smoking and asthma incidences as key variables in the study, thereby excluding other variables that existed in the CHIS dataset. Additionally, as highlighted through our conceptual framework, we also only focused on personal and environmental factors affecting the relationship between smoking and asthma. The theories we excluded from the study, but were closely related to the research problem, include the stems theory, social learning theory, and social exchange theory.
They were excluded from the study because they did not have a health-related focus. Based on the external validity of this review, this study is mostly generalized to African immigrants living in California. It will be difficult to extrapolate the same findings to the same ethnic group in other states because different states have different health policies and socioeconomic conditions that may affect the research outcomes.
Limitations of the Study
According to Mangal and Mangal (2013), limitations of a study often refer to issues that are outside a researcher’s control. One key limitation of our study is that the findings obtained are limited to the time (or period) the data presented in the California Health Interview Survey was collected. This limitation could affect the immigration status of the target population, the population sample and socioeconomic conditions of the time.
We also assume that the limitations associated with the collection of data portrayed in the CHIS would also be the same limitations in our study. The limitation transferred from the CHIS could affect the trustworthiness of our research findings. For example, researcher bias or existing stereotypes surrounding Africans could have affected the formulation of information in the CHIS. Thus, the validity and reliability of our findings are intertwined with the reliability and validity of the findings presented in the CHIS (Bowling, 2014).
Summary and Conclusion
In this section, we have shown that researchers have always investigated the relationship between smoking and asthma. Particularly, they have demonstrated that these two variables share a positive relationship because increased smoking often increases asthma incidences. Their findings have also shown that smoking often causes irritation along the air pathways, thereby leading to asthma. Similarly, they have also shown that the habit damages hair-like structures (cilia) along the air pathways, leading to an exacerbation of the condition.
This data has often been presented as a general relationship between smoking and asthma. Specialized studies have often focused on age differences and income groups to explain the same relationship. Those that have further broken down the demographic divide have investigated the relationship between smoking and asthma among specific immigrant groups such as Hispanics and Asians. The relationship between smoking and asthma among African immigrants is a relatively under-researched area because studies have always neglected this immigrant group.
This paper seeks to fill this research gap by exploring the relationship between smoking and asthma among adult African immigrants. As highlighted above, the main variables are smoking (independent variable) and asthma as the dependent variable. Our main source of data will be the CHIS. Since we are using the quantitative co-relational research approach, reliability and validity issues associated with the data collection process of the CHIS mostly limit us.
Nonetheless, we assume that the information contained in the CHIS is reliable and credible. We also assume that the findings presented in this report will be representative of all adult African immigrants in California. Using the socio-ecological model, the present study would fill the aforementioned research gap by highlighting the personal and environmental factors that could affect the relationship between the variables under study (smoking and asthma).
This study will help us to understand whether there is an association between smoking and asthma incidences among adult African immigrants in California. From our findings, we will be able to ascertain whether the research outcome will be consistent with other research studies, which have shown a positive relationship between the two variables. The findings of this study could have a positive impact on social change because they could help to reduce the impact of asthma incidences within the target population. Furthermore, they could inform policy decisions affecting the research issue.
Literature Review
Introduction
This literature review section is divided into different sections. The first section outlines the literature search strategy which includes information about the accessed library database and the search engines used to get information about past research studies that have explored the research issue. In this section, we also list the search terms and provide a combination of the same to present an outline of how we derived relevant research materials from the databases. Lastly, in this section of the report, we explain that the main literatures consulted in this paper are peer-reviewed articles in the form of books, journals, and credible website sources.
All the sources consulted in this review are not more than five years old (they are published between 2012 and 2017). The main section of this chapter is the analysis of relevant literature, which contains a review of more than 60 articles. Through an analysis of this literature, we outline the research gap that will be filled through an exploration of the research topic. The subsequent section of this report is the literature search strategy.
Literature Search Strategy
The literature search was conducted from reputable sources of peer-reviewed articles available from Google Scholar, Google Books, NCBI, and MEDLINE. Most of the articles sourced from these databases are openly available. The key research terms used to get the articles were “African,” “Immigrants,” “Asthma,” and “Smoking.” Most of these terms were derived from the variables under study and the nature of the research topic. Excluded from the review were research articles that were published earlier than 2012. We also excluded articles that came from commercial websites, blogs and other online sources that were unreliable. There was a strong bias to include only articles that were peer-reviewed.
Conceptual Framework
In this paper, we have shown that the socio-ecological model will be the main conceptual framework for our study. However, other researchers have used other types of conceptual frameworks to explore the interaction between human factors and environmental factors while trying to assess or predict health outcomes. For example, Kapp, Simoes, DeBiasi, and Kravet (2016) used the systems theory to investigate how immigration patterns affect health outcomes in America.
Jayasinghe (2015) also used the same conceptual framework to explain how social issues affect health outcomes. Both researchers said that the systems theory provided a reliable conceptual framework for understanding how natural and social systems interact. They also said that the same framework properly conceptualized population health outcomes as dynamic, open, and adaptive systems. Broadly, these researchers have managed to demonstrate that human health outcomes are products of interrelated parts of subsystems, thereby enhancing our understanding of interactions between micro-meso-macro levels of health (Jayasinghe, 2015).
Researchers have also used the social construction theory as another conceptual framework for understanding the interrelations between different health variables. As highlighted in the works of researchers such as Onono et al. (2015), this theoretical foundation explains how socio-cultural and historical factors often shape people’s health outcomes. This theory would have been relevant to our research issue because it has been used by many researchers to explain the lived experiences of oppressed or minority communities. However, the main flaw of this theory (regarding its use in our research study) is its excessive bias on cultural and historical factors as a predictor of health outcomes. In this regard, it has no proper consideration of other factors that could affect health outcomes.
The main issue to point out in this analysis is that these conceptual frameworks have mostly been used to effect change or institute human behavioral changes as a prerequisite for their use. This focus does not explain the nature of our study because it does not institute change. Instead, it strives to describe a health phenomenon. The socio-ecological model adopts a broader view of health issues. This is why it was the most appropriate model for the paper.
Effects of Immigration on Health
Different researchers have explored the relationship between immigration and asthma. Such is the case of Cabieses, Uphoff, Pinart, Antó and Wright (2014) who conducted a systematic review to analyze the effect of immigration on the relationship between asthma and smoking. They conducted this review according to the guidelines stipulated in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and found that there were significant differences in allergic reactions for populations that lived in their countries of origin and those that emigrated to other countries (Cabieses et al., 2014).
They also found that the level of development in the host countries significantly affected the level of asthma developed by the immigrants. Fox, Entringer, Buss, DeHaene, and Wadhwa (2015) have also demonstrated that immigrants who lived in developed countries had higher rates of asthma compared to those who lived in less developed countries. The researchers also established that there was a strong influence of the environment on the development of asthmatic conditions among the sample populations (Fox et al., 2015). Additionally, they established a higher prevalence of asthma among second generation immigrants compared to first generation immigrants because the latter group was not exposed to the environmental conditions of the host countries as much as the former group.
This assertion showed that the length of stay in the host country was directly related to the development or seriousness of asthmatic conditions. These findings were consistent with research studies conducted by Ro (2014), which upheld the same conclusion across sample groups of different nationalities, study populations and age groups. However, he established differences across these social groups when the linear model was used (Ro, 2014). The differences also emerged when the respondents compared the findings across early and later stages of immigration. Differences in time of residence also yielded the same outcomes.
In a different study to investigate asthma incidences among Asian immigrants living in America, Becerra, Scroggins and Becerra (2014) established that Chinese, Filipino, South Asian, and Japanese immigrants reported a positive relationship between asthma and immigration. The same was true for Korean immigrants because the study showed that there was a positive relationship between asthma prevalence and immigration status (Becerra et al., 2014). The researchers used a linear regression model to come up with the findings after relying on data prepared by the California Health Interview Survey 2001-2011.
Garcia-Marcos et al. (2014) also conducted a study to investigate whether immigration affects asthma incidences among immigrants and came up with the same findings. In other words, they established that immigrants to western countries often adopt the same allergic reactions that host populations suffer from. The researchers used a mixed method approach to conduct the review by first gathering data using questionnaires from 13-14 year old immigrants living in the USA. They also gathered the views of parents who had children aged 6-7 years old using secondary research data (Garcia-Marcos et al., 2014).
Their findings showed a weak association between immigration and higher incidences of asthma. Thus, they believed that the reduced risk of asthma was often related to immigrants who had lived in America for the shortest time. This finding is consistent with the views of Lopez and Golden (2014) who say an increased stay in the host countries, often leads to the loss of protective pre-immigration environment that would have otherwise helped immigrants to lower their risk of asthma.
Corlin, Woodin, Thanikachalam, Lowe, and Brugge (2014) investigated how immigration affected the health outcomes of Chinese immigrants and after sampling the health outcomes of more than 147 immigrants, they established that the immigrant population had better health outcomes compared to the native populations. The researchers also used bivariate and multivariate models to compare the prevalence of diseases among the two population groups, as well as the clinical biomarkers associated with the study focus (Corlin et al., 2014). To explain their findings, the researchers said that healthier diets, minimal exposure to cigarette smoke and increased physical activity among the Chinese immigrants was mostly responsible for their positive health outcomes.
A study by Camacho-Rivera, Kawachi and Bennett (2015) also investigated the relationship between immigration and health outcomes by exploring the effect of race, ethnicity and country of origin on the risk of developing asthma. The researchers used 2,558 non-Hispanic white and Hispanic children to investigate this research phenomenon and found that lifetime asthma incidence was prevalent in less than 9.1% of the population (Camacho-Rivera et al., 2015).
They also found no significant differences in asthma rates between Hispanic and non-Hispanic respondents. This study highlighted the importance of moving beyond racial or ethnic classifications to develop policies surrounding asthma management because these classifications often mask different subgroups of people who are at high risks of asthma.
Barr et al. (2016) conducted a study to test whether ethnicity is a dependent variable in the prediction of asthma incidences among immigrant populations in the US by analyzing whether the condition was prevalent among Hispanics and Puerto Ricans more than other immigrant groups. They found that asthma was more prevalent among second-generation Hispanic and Puerto Rican immigrants than first generation immigrants were (Barr et al., 2016). They partly explained this finding using differences in smoking patterns among the sampled population groups. Their study included a sample of 16,415 Hispanics and Latinos (Barr et al., 2016).
In a different study to evaluate asthma admissions using ethnic variations, Sheikh et al. (2016) found that South Asian immigrants reported the highest hospital admissions attributed to asthma. These findings were developed after evaluating two main ethnic groups – whites and South Asian immigrants. However, the researchers failed to take into account sex-related differences that would have affected health outcomes. Benchimol et al. (2015) also used South Asian immigrants as a sample group to estimate the incidence of asthma and immune-mediated diseases among immigrants in western countries. They used population-based cohorts of respondents who suffered from asthma and diabetes to undertake the review and found that adults from South Asia had a higher predisposition to asthma compared to other ethnic immigrant groups (Benchimol et al., 2015).
This finding contradicted the view of many studies highlighted in this literature review because other studies have consistently shown that immigrants from other countries had a lower risk of developing asthma compared to host populations. However, the explanation for this inconsistency could stem from the fact that the findings of Benchimol et al. (2015) are mostly attributed to a genetic predisposition to the disease among South Asian immigrants.
Mahmoudi (2016) conducted a broader review involving more than 40 countries to understand the effect of immigration on asthma incidences and found that immigration was associated with a low incidence of asthma. He developed these findings after conducting a survey of more than 326,000 adolescents from more than 40 countries. The survey also included a population of 207,000 children from 30 countries (Mahmoudi, 2016). However, the association between immigration and asthma incidence was limited to affluent countries.
Reed and Barosa (2016) have also explored the role of nativity in explaining the advantage enjoyed by immigrants compared to their host populations, when it comes to asthma prevalence. To explain this advantage, they explored the health outcomes of two groups of immigrants – refugees and non-refugees. The findings revealed that refugees were disadvantaged when it came to access to health care services, thereby suffering poor health outcomes compared to their non-refugee counterparts. Comprehensively, these studies show there is an association between asthma and immigration, with immigrants suffering lower incidences of asthma compared to host populations.
Effect of Environmental Exposures on Health
In an effort to understand the effects of environmental exposures on health, Im et al. (2015) outlined the case of a researcher, Johnson, who used an innovative framework to separate a host of factors affecting asthma incidences into different constituents. His analysis concentrated on factors that affect the design, construction and conditions of the dwellings, which immigrants lived in. The researcher found that the risk of developing asthma was directly correlated to the nature and type of dwelling (Im et al., 2015). Im et al. (2015) said this relationship was a product of the interaction between culture and environment.
In a separate study, Rumrich and Hänninen (2015) found that the complexity associated with asthma management was directly associated with the immigrants’ ability to communicate fluently in English and partly on whether they were born in the U.S, or not. They also established that asthma was more severe for immigrants who were relatively acculturated to their host countries, compared to those who were not (Rumrich & Hänninen, 2015). Their findings corresponded with a similar study by Chiu et al. (2016), which highlighted the lower incidence of asthma among new immigrants compared to those who had been in the host nations for a long time. This comparison implies that western risk factors increased the risk of developing asthma. This fact was supported by studies, which investigated the same issue among Arab-Americans (Im et al., 2015).
In a research study conducted by Rottem, Geller-Bernstein and Shoenfeld (2015), it was established that environmental factors and the age of immigration affected people’s predisposition to asthma. The study went further to explain that the level of immunoglobin E was relatively higher among immigrants compared to the local population, thereby decreasing their predisposition to asthma (Rottem et al. 2015). The researchers also explored the possibility of a reversal of allergies because of parasitic infections. In this regard, they proposed that secondary prevention guidelines should be introduced to immigrants before they settle in their host nations, as a strategy to prevent asthma attacks (Rottem et al. 2015).
Studies that have tried to explore the impact of the environment on the health of immigrants have found it difficult to isolate the environment from other socioeconomic factors affecting immigrants that would ultimately affect their health as well (Okechukwu, Souza, & Davis, 2014). For example, a study by Guruge, Birpreet, and Samuels-Dennis (2015) to investigate the impact of environmental conditions on older women immigrants in Canada found that SES, cultural beliefs, gender norms, and influences of the physical and social environment weighed heavily on immigrant health. The studies also showed that older immigrant women were more likely to have health problems because of poor access to health care services and the underutilization of preventive health services (Guruge et al., 2015).
Martinez et al. (2015) say that some of the problems faced by immigrants living in America are partly caused by unfavorable immigration policies. For example, they say unfavorable immigration policies often affect access to health care issues (Martinez et al., 2015). They came up with these findings after reviewing eight health databases, which showed that anti-immigrant sentiments often affected the health outcomes of immigrants because it limited their ability to access health care services. Rhodes et al. (2015) have also come up with similar findings after investigating the effect of immigration policies on immigrant health in America.
Flynn, Carreón, Eggerth, and Johnson (2014) say that understanding the impact of someone’s work environment on their health goes beyond merely understanding how their work presents social hazards and risks to their wellbeing. Indeed, as explained by Arcury (2014), someone’s work also affects other aspects of their social wellbeing, and by extension, their health (work is the major incentive for many people who emigrate to the U.S).
According to Pichardo-Geisinger et al. (2014), many immigrant groups often experience deteriorating physical health after working in the US for some time. They made this finding after reviewing the physical health of a group of Latino immigrants working in the US. The link between work and immigration occurs through the understanding that work often alters the physical environment of immigrants, thereby putting their physical health and those of their family members at risk of deterioration.
Socioeconomic Status and Asthma
The effect of socioeconomic status and asthma has emerged in several research studies that have tried to investigate the relationship between immigration and asthma incidences. Most of these studies have developed findings that have overlapped with similar findings from researchers who have studied the influence of the environment on the incidence of asthma attacks. According to Acton (2012), most immigrant groups living in America have a lower socioeconomic status.
In fact, he says that most of them have household incomes that are below $50,000 (Acton, 2012). Most of the houses or dwellings that these immigrants live in are overcrowded. Kelly, Glick, Kulbok, Clayton, and Rovnyak (2012) estimate that one-quarter of them are this way. Owing to these conditions, most of these homes create adverse environmental conditions, such as dampness or moulds (44%), pests (28%), and poor ventilation (26%) (Acton, 2012). These conditions are known to increase the incidence of asthma and atopic diseases. Similar studies have shown that at least one of the aforementioned adverse conditions was found in at least 67% of homes inhabited by immigrants (Kelly et al., 2012).
Furthermore, they found that multiple hazards were present in more than 27% of similar homes inhabited by immigrants. Grzywacz et al. (2012) say that children of recent immigrants showed symptoms of asthma one year after immigration. In detail, these symptoms were suggestive of asthma (4%) and atopic disorders (10%). Nonetheless, they often suffered from poor diagnosis because only 2% of this population was diagnosed with asthma or the atopic disorders.
A study by Reingle, Caetano, Mills, and Vaeth (2014) shows that although the incidence of asthma among Mexican immigrants was lower than other immigrant groups, it was mostly attributed to poor housing conditions. A scholar, J.S Slitt and his colleagues from the university of Colorado, said that the most common housing issues affecting this immigrant population was plumbing leaks, development of mould, dampness, and pest infestation (Sternberg et al., 2016). Based on these findings, the researchers proposed that asthma management strategies should be multifaceted and more importantly address housing issues and access to health care concerns.
Studies conducted by Landsbergis, Grzywacz, and LaMontagne (2014) have also shown that lower SES is often related with increased asthma incidences, especially among immigrant populations. Differences in race and ethnicity have also been associated with higher rates of asthma attacks, as explained by Abraído-Lanza, Echeverría, and Flórez (2016) who say that the two factors are predictors of health indicators, such as access to health care and health insurance.
The disproportionate nature of asthma and SES has led many researchers to delineate this relationship and to highlight the underlying factors that moderate this relationship. For example, Borges, Orozco, Rafful, Miller, and Breslau (2012) conducted a study to investigate the extent that SES influences asthma incidences among African-American immigrants and Latino youth. Studies that have undertaken the same analysis have used parental SES, education standards and family income as predictors of SES (Kelly et al., 2012).
Their findings have generally shown that decreasing SES scores was directly associated with increased adjusted odds of asthma. Nonetheless, as explained by Riosmena, Wong and Palloni (2013) these studies have also shown that acculturation was among the strongest moderating variables for understanding the incidence of asthma among immigrant populations.
Studies that have investigated the impact of SES on asthma incidences have also studied African-American populations in America and found that the poorest children were most affected by asthma (Carroll, 2013). The same finding was revealed in studies that investigated the same research issue among non-Hispanic blacks and non-Hispanic white populations (Kelly et al., 2012). In ethnic-stratified models, researchers such as Thakur et al. (2013) and Beck, Simmons, Huang, and Kahn (2012) have not found statistically significant relationships between maternal education levels and asthma incidences across different ethnic or racial groups.
However, in small high-risk cohorts of children within the Hispanic communities, there was a relationship between ethnicity and asthma levels when the researchers adjusted different SES metrics. One advantage of these studies is the requirement that the respondents identify themselves as African-American or Hispanic before being included in the study (Thakur et al., 2013). This provision helped the researchers to capture the cultural influences that would have affected their research outcomes. In addition, the respondents included in the study must have had a physician diagnose them as asthmatic within the past two years. There was also a control population, which included respondents without any symptoms of asthma or any prior diagnosis of the same condition (Beck et al., 2012).
Collectively, through the studies, we find that SES could affect the incidence of asthma among different racial and ethnic populations in the US. This fact outlines the presence of different confounding factors that could ultimately affect the relationship between SES and asthma incidence. Generally, these studies have shown that urban populations living in low-income settlements suffer a high risk of asthma because they are exposed to harmful indoor allergens that increase their predisposition to asthmatic attacks. Outdoor pollutants have also been established to exacerbate their asthmatic conditions (for those who suffer from the condition in the first place).
Relative to this fact, Carroll (2013) adds that, “child psychosocial, socio-emotional, and anthropometric factors, such as obesity, are associated with both low SES and asthma, and thus are important exposures to consider when attempting to delineate the relationship between SES and asthma, and potential effect modification by race/ethnicity” (p. 1180).
A study done by Gong et al. (2014) also emphasize the need to understand the effect of social and economic influences on asthma incidences after evaluating how parental SES affects the risk of asthma among their offspring. The researchers established that there was a direct relationship between household income levels and the health outcomes of children growing up in the same settings (Gong et al., 2014).
The researchers also established a relationship between asthma incidences and educational levels within different household settings because there was an association between high education levels and lower risks of asthma, as well as an association between high incidences of asthma and lower education levels. They developed these findings after studying a cohort of 211,500 children born between 2006 and 2008 (Gong et al., 2014).
Keet et al. (2015) investigated whether neighborhood poverty and residence status (inner city and non-inner cities) were associated with asthma incidences. Their study aimed to evaluate whether residency status within inner cities and non-inner cities could help to predict the incidence of asthma (Keet et al., 2015). After conducting a secondary analysis through a national databse, the researchers found that inner city residency was associated with higher incidences of asthma (Keet et al., 2015).
However, this association was not statistically significant after adjusting for specific social variables, such as race, ethnicity and religion. Based on these findings, the researchers claimed that although the incidence of asthma was highest among inner city neighborhoods and among specific immigrant populations, such as Hispanics and Puerto Ricans, demographic factors mostly explained this relationship, as opposed to inner city residency (Keet et al., 2015). This finding contradicted the views of some researchers highlighted in this paper who said SES could be used to assess the risk of developing asthma. Instead, it draws our attention to demographic factors, as opposed to SES, as a predictor of asthma incidences.
Effects of Smoking on Health
As mentioned in this report, many studies have investigated the relationship between smoking and asthma. Different immigrant groups in America report different levels of smoking. In one study conducted by Burgess (2014), South East Asian communities living in America are among the heaviest smokers. After collecting the views of 60 leaders within this ethnic group (using semi-structured interviews), the researchers also discovered that smoking tobacco was a cultural heritage issue for this immigrant group (Burgess, 2014). In other words, it was used to convey social status and was a symbol of respect.
Furthermore, the study revealed that many older social males suffered from isolation and smoked to alleviate the stress associated with it (Burgess, 2014). Based on these assertions, the findings suggested that community leaders in South Asian immigrant communities needed to promote a cultural shift in smoking to prevent their members from promoting this habit.
Allem et al. (2012) conducted a study to investigate how the environment often affects smoking habits when immigrants move from their countries of origin to America. After investigating the smoking behaviors of Koreans in Seoul and Koreans in America and collecting data using telephone surveys, they found that smoking patterns differed for both groups of Koreans (Allem et al., 2012). Although they found that there was a peak in the relationship between smoking habits and immigrants’ age, at 35 years, they found that South Koreans living in America smoked more than those living in their home countries (Allem et al., 2012). They mostly attributed this finding to social role transitions between Koreans living in America and those living in their countries of origin.
In a study to investigate the smoking-related mortality rates among Latino and Hispanic immigrants, Fenelon (2013) found that these immigrant groups had lower levels of smoking-related deaths compared to whites living in America. This finding was established, irrespective of the low SES of the immigrants (Fenelon, 2013). However, culture was established as a moderating variable that could influence the smoking patterns between immigrants and populations living in the host nations.
Generally, these findings have shown that smoking worsens people’s health. The evidence supporting this assertion is abundant. For example, in one study conducted by Polosa, Caponnetto, and Sands (2012) to care for smoking asthmatic patients, it was established that smoking asthmatic patients could present a distinct disease entity, which manifests as asthma complications and chronic pulmonary disease obstructions. In the assessment of asthma management, smoking could have clinical and prognostic implications. Nonetheless, the researchers pointed out that smoking severely increases the impact of asthma attacks (Polosa et al., 2012).
Spears et al. (2013) also arrived at the same conclusion when he investigated the incidence of asthma among affected persons who started smoking. To meet his objectives, the researchers conducted an exploratory study on three groups of respondents. The first one comprised of 22 current smokers. The second one was made up of 21 people who had never smoked. The last group comprised of 10 ex-smokers. The researchers examined their blood and sputum cytokine concentrations to understand the effect of smoking on their risk of asthma. The results showed that smoking had increased sputum cytokine levels, thereby supporting the view that smoking increased the risk of asthma (Spears et al., 2013).
Role of Acculturation
Researchers, such as Reiss, Razum, and Lehnhardt (2015) have explored the impact of acculturation on the smoking habits of different immigration groups and found gender differences in immigration smoking patterns between men and women. Men reported the highest smoking incidence compared to women. Similarly, women who had undergone years of acculturation were more susceptible to smoking compared to those who had not (Reiss et al., 2015). The researchers came up with these findings after retrieving and analyzing 27 studied published between 1998 and 2013. Generally, they pointed out that, different groups of immigrants from different countries had reached different stages of smoking where non-western countries were in early stages of smoking while western countries were in later stages of smoking.
Reiss, Sauzet, Razum, Breckenkamp, and Spallek (2014) did a similar study where they compared the prevalence of smoking among Turkish immigrants who had emigrated to Germany and the Netherlands. They used two sets of data to come up with their findings. The first set of data was the German 2009 micro-census, while the second set of data was the Dutch POLS database. They also developed logistic regression models for age-specific smoking habits and sex-specific smoking behaviors. Generally, the researchers found that the immigrants had changed their smoking behaviors to suit those of their host nations (Reiss et al., 2014).
The strength of the adaptation was correlated with their length of stay. This relationship was stronger for Turkish immigrants who had left their country of origin before reaching 18 years. These findings support the views of similar researchers in this paper who has shown that the length of stay in immigrant countries often affects health habits of immigrant groups.
Printz (2015) conducted another study to investigate the effect of immigration and acculturation on smoking among Latino and Asian immigrants in America. The researchers used a sample of 3,249 Latino and Asian immigrants and found that male immigrants smoked four times more than their female counterparts did (Printz, 2015). This finding could be translated to mean that male immigrants smoked 2.5 more cigarettes per day than their female counterparts did.
These findings were also consistent with other studies that showed that the length of stay in the host country was a strong moderating factor for smoking habits among immigrants because Printz (2015) found that increased length of stay often leads to the increased frequency and prevalence of smoking among the sampled population. Their findings also showed that immigrants who acculturated themselves well, in terms of English proficiency and citizenship acquisition benefitted from reduced smoking behavior.
Li, Kwon, Weerasingh, Rey, and Trinh-Shevrin (2013) also arrived at the same finding when they explored the impact of smoking on Asian communities living in New York because they established that acculturation explained the consistent rise in smoking behavior among these immigrants, while the rate of smoking in the general population decreased. These findings were developed through an analysis of data from the REACH US Risk Factor Survey (2009-2011).
Gorman, Lariscy, and Kaushik (2014) also explored the role of acculturation in predicting the smoking behaviors of immigrants in the US after finding that female immigrants smoke less than their male counterparts do. They found that gender had a moderating effect on acculturation because differences in smoking behaviors between the sexes could not be holistically explained by acculturation alone (Gorman et al., 2014). They came up with this finding after analyzing data from 3,249 Latino and Asian immigrants living in the US.
In a study to investigate the impact of nativity on the relationship between asthma and immigrants, Arsen (2013) investigated the influence of a person’s immigration status on their risk of developing asthma. This study was prepared against a background of research studies that showed immigrants had better health outcomes than their host populations and the understanding (among many sociology researchers) that immigrants had poor SES and were more prone to asthmatic attacks, compared to host populations, which are ordinarily in higher SES (Alkerwi et al., 2012).
The analysis of Arsen (2013) supported the findings of other studies in this paper, which showed that immigrants suffered a lower risk of asthmatic attacks compared to the native-born population. He conducted this study by comparing the risk of asthma among French immigrants and the native population.
Lee, O’Neill, Ihara, and Chae (2013) also explained the importance of understanding how long immigrants have stayed in their host countries, as a prerequisite for understanding their health outcomes, because they explained that although acculturation improves the SES of immigrants, their continued stay in the host countries is associated with worsening health outcomes. The researchers developed these findings after conducting a cross sectional study that used data from a survey analyzing the behaviors of immigrants who came to the host nations between 2003 and 2004. Their findings implied that increased stay in the US often leads to the adoption of unhealthy lifestyle behaviors, which are responsible for poor health outcomes (Lee et al., 2013).
Relevant Factors Identified in the Literature Review
Throughout our review, we have noted that there is increased attention to understand the effect of asthma and smoking among immigrant communities, not only in America, but around the world as well. This concern is partly caused by the rising prevalence of asthma and associated complications, globally. Most of the studies we have sampled in this literature review have explored the causal pathway of asthma and allergies.
However, there have been contradictory and conflicting findings regarding the interplay between allergy and the socioeconomic determinants of health. Immigration status is at the top of the list of factors that have been poorly understood, but as seen from this literature review, many researchers have tried to explain it. Indeed, based on an extensive analysis of this literature review, we have established that different researchers have struggled to explain the relationship between immigration and asthma, as well as explore the effect of socioeconomic status on human health outcomes.
The focus on socioeconomic status was of importance to our review because, in our study, we are focusing on African immigrants whose health has been proved to be affected by their socioeconomic conditions. In the review, we have also explored the role of acculturation on the smoking habits of immigrants and found that the longer the immigrants stayed in the host countries, the higher their intensity and frequency of smoking. We also established that there are significant gender differences in acculturation among different immigrant communities that would ultimately affect their general smoking behaviors.
While these studies (generally) have good merit in the way they were designed, we did not come across any study that focused on African immigrants as a unique sample population. In fact, the only studies that were close to our target population were those that sampled the health outcomes of African-Americans. However, these two populations are not the same. Additionally, the latter is not an immigrant group, per se. Based on this fact, there is a significant gap in the literature because health studies have failed to recognize the unique socio-cultural and economic dynamics of African immigrants that affect their health. This study seeks to fill this research gap by investigating the association between smoking and asthma incidences among adult African immigrants in California.
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