Shirley M. Solberg

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THE SOCIAL DETERMINANTS OF HEALTH: AN EXPANDED CONCEPTUAL FRAMEWORK FOR NURSING

                If our goal is to reduce health disparities rather than to just study them, nursing research must include a major focus on resources such as income, education, access to care, social and political power, and human rights. We will not achieve this goal by focusing on individual behaviours and risk factors alone. We need a new paradigm that recognizes societal factors as primary pathogenic forces in the major health problems facing the U.S. today.

—Flaskerud and Nyamathi (2002, p. 139)

More than a decade ago in a guest editorial in Nursing Research, Flaskerud and Nyamathi (2002) essentially called on nurse researchers to expand their thinking about health and the environment by embracing a new paradigm that would enable them to move beyond what were traditional approaches to nursing research, in order to reduce health disparities. This was not the first in recent times that nurses were asked to think more broadly about how the environment might have an impact on health. In a call to approach theory development in a new way Chopoorian (1986) believed that nurses’ “lack of consciousness of environment” (p. 43) limited nurses’ abilities “to turn their attention to the conditions that control, influence, and produce health or illness in human beings” (p. 53). Stevens (1989) advocated a critical social theory approach so that “nurses may reconceptualize their understanding of the environment to encompass social, political, and economic worlds” (p. 59) to improve nursing care. Likewise, Butterfield (1990) suggested that “upstream” thinking was needed for nurses to address “social, environmental, and political determinants of health” (p. 1). More recently, some concrete approaches have been put forward on how to broaden the conceptualization of the environment and health. Reutter and Kushner (2010) suggested nurses tackle health inequities through a critical approach using the social determinants of health (SDH) as a guide.

The centrality of the concepts of health and the environment to nursing as a practice and a discipline has been well recognized beginning with Nightingale and continuing to the present day (Risjord, 2010). Health and the environment are core concepts in most, if not all, theories and frameworks of nursing and a clear conceptualization of health, and the environment remains central to what we do as nurses in practice, education, and research (Meleis, 2012). However, in many of the nursing models and frameworks, the concept of the environment has been limited, or at least interpreted to be somewhat limited, to the more immediate environment of the individual or family. Even in many models or frameworks that present a broader view of the environment, there is no account taken of the many structural factors in society (economic, political, and social), that as the SDH frameworks have illustrated, produce a huge impact on health. How the concepts of health and the environment are understood and used can be limiting or enabling, not only for improving health of individuals and populations, but in reducing health disparities and inequities.

Health disparities and health equities are important because nurses are ethically mandated to help individuals, families, communities, and populations by protecting, promoting, and restoring health in the many interactions that nurses have with the client, however defined (American Nurses Association, 2015; Canadian Nurses Association, 2008; International Council of Nurses, 2012). Additionally nurses have both an ethical requirement and a social responsibility for broader actions around equity, fairness, and social justice when it comes to responding to the health and social needs of human populations on a local, national, international, and increasingly a global scale (Anderson et al., 2009; Canadian Nurses Association, 2010; Pauly, 2013). To fulfill this mandate requires a framework that is capable of providing a solid understanding of health and the factors that influence health within an environmental context that can inform our thinking and thus practices. Equally important is an understanding of what accounts for the differences or disparities in health that exist. Understanding individual health and its distribution in populations is complex because of the many factors that have an indirect or direct impact on health, so a comprehensive framework is required: one that takes into account the various interacting factors and conditions that influence health (Solar & Irwin, 2010). An SDH framework is a good fit for understanding the myriad of influences on health because it more closely mirrors the environment in which health and illness, including health disparities and inequities, are created and experienced and thus could enhance nurses in their ability to fulfill their professional mandate (Canadian Nurses Association, 2005; Mahony & Jones, 2013; Reutter & Kushner, 2010).

An SDH framework is evidence-based and broadly addresses the many factors that affect health (Braverman, Egerter, & Williams, 2011; Commission on the Social Determinants of Health [CSDH], 2008; Muntaner, Ng, & Chung, 2012; Marmot & Wilkinson, 2006; Raphael, 2004). The SDH framework has evolved over the past four decades as evidence for and knowledge of the SDH has accumulated (Irwin & Scali, 2007; Marmot & Wilkinson, 2006; Raphael, 2004), the concepts clarified (Braverman, 2006; Chang, 2002; Dahlgren & Whitehead, 2006; Kelly, 2010; Williams, 2003), and the knowledge translated and promoted as a means to address the health of individuals and populations (Canadian Nurses Association, 2013; CSDH, 2008; Muntaner, et al., 2012). A SDH framework or elements of this framework have been widely advocated, adapted, and used as a policy framework by a number of governments (King, 2000; Turrell, Oldenburg, McGuffog, & Dent, 1999) and organizations (Canadian Nurses Association, 2013; Centers for Disease Control and Prevention [CDC], 2010; Royal College of Nursing, 2012; Solar & Irwin, 2010). The SDH have been adopted as the basis for conceptual frameworks in education programs in nursing (Cohen & Gregory, 2009; Gillis & MacLellan, 2013), as well as for public health and community health programmes (Villarruel, Bigelow, & Alvarez, 2014) and community health initiatives internationally (Blas & Kurup, 2010). SDH frameworks have been used in nursing research (Wuest, Merritt-Gray, Berman, & Ford-Gilboe, 2002) and for conducting and translating research into policy (Ommer, 2006; Ommer With the Coasts Under Stress Research Project Team [Solberg], 2007). The purpose of this chapter is to present the SDH framework as a basis for nursing practice, education, and research.

WHAT ARE THE SOCIAL DETERMINANTS OF HEALTH?

There are a number of conceptualizations and definitions of the SDH and the categories or elements that are to be included in the list of determinants (Graham, 2004; Raphael, 2004). In some of the conceptualizations, the terms determinants of health and SDH are used interchangeably. In other definitions, the SDH are considered as a subset of the determinants of health or of population health and used more particularly to refer to societal factors, which usually do not include individual factors such as biology or genetics (MacDonald, Newburn-Cook, Allen, & Reutter, 2013; Williams, 2003). The role of health care systems/access to health care as a determinant of health has been much contested, with some definitions and lists of the SDH including it (Dahlgren & Whitehead, 2006; Public Health Agency of Canada, 2013), others not (Wilkinson & Marmot, 2003), and some authors advocating for its inclusion (McGibbon, Etowa, & McPherson, 2008).

Some of the variation in conceptualization represents a developmental stage in how to best conceptualize the SDH (WHO, 1986). Early definitions or conceptualizations of the SDH encompassed societal factors that were thought to contribute to or determine the overall health of a population or a country (Wilkinson & Marmot, 2003). Other variations in definitions embody more ideological or political differences. Raphael (2011) illustrated the importance of ideological differences through an examination of discourse in six different SDH concepts, and the willingness or not, of the proponents of the definition to link the concept of the SDH with broad policy implications or development that would address inequities in the health of the population. Over the past decades, definitions of the SDH have been refined and broadened to include the phenomena of health inequities, inequalities, or disparities (Solar & Irwin, 2010). Based on research evidence, the SDH and health inequities have been found to be strongly linked and this link is encompassed in the WHO framework for SDH and social determinants of health inequities (CSDH, 2008). The latest WHO (2014) definition of the SDH that is in widespread use is:

EVOLUTION OF SOCIAL DETERMINANTS OF HEALTH

This section is an overview of the evolution of the SDH as a concept and framework. See Table 28.1 for some of the main milestones in the development of the SDH. It is not meant to be a comprehensive account because that is well beyond the scope of this chapter. Many countries have their own history incorporating and adapting the SDH within more local contexts (Edwards & Cohen, 2012), and some of these developments may or may not have contributed to the overall development of the SDH as a conceptual framework. It is difficult to trace when the first use of the term “social determinants of health” came into common use. One of the challenges is that the word “determinant” has a number of meanings, for example “a factor that decisively affects the nature or outcome of something” (“Determinant,” 2014). Other meanings of determinants are causal factors or influences. Nevertheless, as some authors have indicated, the idea of health being rooted in social circumstances is not new, with a gradual shift from thinking about health strictly as a biomedical concept that is linked to the absence of disease to a social concept that links health to life circumstances and determined by social, political, and environmental factors (Graham, 2004; Raphael, 2004; Williams, 2003). This shift has been one of evolution and has had a number of influences or developmental milestones. The work conducted under the leadership in the WHO has had a huge impact on the development of the SDH as a way to think about health and health inequities and as a framework for health policy (Irvine, Elliott, Wallace, & Crombie, 2006). A description and analysis of the main events that contributed to this history is presented by Irwin and Scali (2010) and by Irvine et al., (2006). Irwin and Scali traced this development from the first WHO constitution in 1946 that included a goal to address “social roots of health problems” (p. 5) to the 1960s and 1970s, with an increasing emphasis on how social, economic, and political factors affected health, to the concentrated work on the SDH in the 1990s. This culminated in the setting up of the CSDH by the WHO in 2005 and a final report (CSDH, 2008). The work by the WHO on the SDH continues. Throughout these developments and in keeping with principles of the WHO, there was an emphasis on health as a human right and promoting strategies to reduce the health inequities that have been identified within countries, between countries, and globally; hence a link to social justice.

Some of the groundwork for the development of an SDH framework predates the work of the WHO and has emerged from developments in medicine and sociology in the early 1920s and 1930s with the creation of a division within medicine known as “social medicine” now referred to as “public health medicine” (Young, 2005) and development of the subdiscipline medical sociology within sociology known as sociology of health (Segall & Fries, 2011). As Porter (2006) indicated in a brief history of social medicine, the early goals in the 1930s in North America and Great Britain “were overtly linked to political programs of social reform” (p. e39). The main area of concern within medical sociology gradually evolved from a focus on the medical professions and organization of health systems to incorporate the roles that society and social structures played in health and illness, with a more recent interest in SDH (Williams, 2003). Others describe it as evolving from early social reform movements and public health, with the focus on living conditions and the environment (Irwin & Scali, 2007). Although all these developments no doubt were influential, the rise of epidemiology and social epidemiology in the past several decades with a focus on distribution and determinants of disease, and later on the determinants of health, helped to establish not only strong evidence in this area, but powerful quantitative methods for researching the SDH (Honjo, 2004; Young, 2005). Integration of such techniques as geographical information systems into health research is promising for providing more evidence for the SDH because it provides the ability to map out areas of greater disparities in health (Bloch, 2011). Other approaches are critical as well in order to more fully understand pathways and explanations of the social phenomena inherent in an SDH framework (Williams, 2003). In some ways the evidence has outstripped our understanding, particularly in how causal pathways work between the broader determinants to the level of population and individual health (CSDH, 2008).

BEGINNING THE DEBATE

A number of authors are credited with beginning the debate about determinants of health. An early use of the term was by McKeown (1976; 1979), who presented strong evidence for the role that behavioral and environmental factors had in the improvement in health. He examined the decline in mortality rates in England and Wales between 1700 and 1971 and linked reduction in mortality to improved social factors, such as access to improved nutrition and living in healthier environments. Healthier environments were marked first by greater hygienic measures than existed previously, improved housing, and later cleaner atmospheres and improved working conditions. In contrast, he suggested medical interventions contributed little to improved health. McKeown (1979) concluded that “in order of importance the determinants of health, at least in the past were nutritional, environmental, and behavioural” (p. 164). His writings are cited as influential in development of the Lalonde Report in 1974 and the health field concept (Crighton, Robertson, Gordon, & Farrant, 1997; Irvine et al., 2006), and the SDH (Frank & Mustard, 1994).

Selected government directions and debates on public health policy have been credited with influencing the development of the SDH as a concept and approach (Graham, 2004). Although the WHO provided much of the leadership on an SDH framework, the recognition of the importance of this approach and developments in other countries were equally important. Some key studies carried out in the 1970s and 1980s in Canada and Great Britain, either as parallel developments or in collaboration with the WHO, are noteworthy in that they are cited as influential in developing our understanding of and the importance of emphasizing the SDH. Western European countries, Australia, and New Zealand were also important contributors to developments in SDH (Irwin & Scali, 2010). Research funding and institutes established in Canada, Great Britain, the United States, and no doubt other countries provided key resources, both financial and human, to carry on the critical work of providing evidence and knowledge creation, transfer, translation, and implementation critical to the further development of the SDH.

Canada

In the early 1970s, the Canadian government released a white paper titled A New Perspective on the Health of Canadians (Lalonde, 1974), usually referred to as the Lalonde Report, which was widely distributed. The new perspective introduced was the “health field concept” consisting of four broad elements: human biology, environment, lifestyle, and health care organization (p. 31). This framework broadened thinking within Canada on what determined health and influenced work on health promotion within the Canadian health system and beyond (Crighton et al., 1997; Pederson, Rootman, & O’Neill, 2005). The report also influenced a debate on an international scale and is widely attributed to beginning a discussion on the SDH (Irwin & Scali, 2010; Robertson, 1998) and public policies to address health inequities (Irvine et al., 2006; Graham, 2004). A second major milestone was the release of the Canadian policy paper Achieving Health For All: A framework for health promotion (Epp, 1986) in conjunction with the WHO’s First International Conference for Health Promotion held in Canada that year (Pederson et al., 2005). In this paper, Epp identified “reducing inequities in the health of low- versus high-income groups” (p. 4) as one of the main challenges to achieving health for all. This conference resulted in the Ottawa Charter for Health Promotion, which identified eight prerequisites believed important for health (WHO, 1986). Later, these factors were modified and described as the SDH (Canadian Nurses Association, 2013). These events were also considered the beginning of a “new health promotion” or “new public health” that was based on a broad conceptualization of health and what influenced health (Robertson, 1998; Scriven & Garmin, 2005). The Ottawa Charter reaffirmed the WHO (1978) Alma-Ata Declaration of “Health for All” and the goal of health equity. In practice and service delivery, health promotion became the main paradigm and thus health promotion and the SDH developed as “two solitudes” (Jackson, Birn, Fawcett, Poland, & Schultz, 2013). Nevertheless, the work of Lalonde (1974) planted the ideas of the SDH as a focus in health circles and they were translated into at least some of the health discourse in Canada, used for health education programs, and eventually adopted by the Canadian Nurses Association (2013) and the Public Health Agency of Canada (2013).

Within Canada, both inside and outside of academic circles, Raphael (2004, 2010) has promoted the concept of SDH defined as “the economic and social conditions that influence the health of individuals, communities, and jurisdictions as a whole” (2004, p. 1). Through work with other academics and individuals in public policy and based on research evidence within Canada, he identified a number of SDH. Raphael’s work on the SDH is widely cited. Funding for research on the SDH is supported mainly through the Canadian Institutes of Health Research (CIHR) established in 2000, but especially the Institute for Population and Public Health (2014), which has as a mandate to “support research into the complex biological, social, cultural, and environmental interactions that determines the health of individuals, communities, and global populations” (para. 1). A core pillar of the CIHR for Gender and Health and Aboriginal People’s Health is social and cultural dimensions of health, and this pillar supports health equity research on the SDH as it applies to gender and aboriginal people (Edwards & Cohen, 2012). In 2005, the Public Health agency of Canada established six National Collaborating Centers (NCCs); one in eastern Canada for the Determinants of Health (Edwards & Cohen, 2012) tasked with knowledge translation, developing networks, and identifying gaps in research.

Great Britain

In Great Britain, a working group was appointed in 1977 to examine and report on the health disparities evident in that country. The work of this group resulted in the release of the 1980 Report on the Working Group on Equalities in Health (better known as the Black Report) (Townsend, Davidson, & Whitehead, 1992). This event was followed by Whitehead’s The Health Divide published in 1987 and later the Acheson Report into inequalities in health (Acheson, 1998); both of which provided updated evidence on inequalities in health because the Black Report indicated the need for an SDH approach. Unlike the Lalonde Report in Canada, which was widely distributed, the Black Report received little attention by the British government (Marmot, 2001; Townsend, et al., 1992). It did garner widespread academic interest and later attention by the WHO and in other countries, most notably the Netherlands, Spain, and Sweden (Irwin & Scali, 2007). One of the important concepts established was that of social inequalities in health (Marmot, 2001). A second and related concept also important was that of a gradient in health status, illustrating that those in lower socioeconomic positions had lower health status than those occupying increasingly higher socioeconomic positions; the higher up in socioeconomic position the better the health status. These were important findings, not only for understanding the SDH but also for identifying the social determinants of health inequities and how health is distributed across populations. At first, the two constructs, the SDH and social determinants of health inequalities, were used interchangeably and frequently confused, resulted in a blurring of “the distinction between the social factors that influence health and the social processes that determine their unequal distribution” [emphasis added]; (Graham, 2004, p. 107). Separating these two major constructs conceptually is particularly important for researchers, practitioners, and policy makers (CSDH, 2008; Whitehead & Dahlgren, 2006).

Marmot and Wilkinson (2006) and academic colleagues in Great Britain produced two editions of the book Social Determinants of Health. This work synthesized the evidence on important SDH, such as early life, labor market disadvantages (unemployment, nonemployment, and job security), psychosocial work environment, transport, social support and social cohesion, food, social exclusion, and neighbourhoods and housing. Their work for the WHO on Social Determinants of Health: The Solid Facts (Wilkinson & Marmot, 2003) was used as a guide for identifying the SDH in many countries that adopted this approach. Although they have been criticized for not including health systems and personal health behaviors in their determinants, they certainly acknowledged the importance of both factors and in an early model of the SDH (Brunner & Marmot, 2006, p. 9) health behaviors were depicted within the model. They asserted that “access to medical care is clearly one of the social determinants of health” (Wilkinson & Marmot, 2003, p. 7), however their purpose in identifying the SDH was to try and understand what caused people to be ill in the first place, or the “cause of causes” as this phenomenon became more widely known, and why others remained healthy. Work on the SDH has continued in Great Britain with an emphasis on advocating the development of policy that would address health inequalities related to these determinants (Marmot, 2010).

United States

In the 1970s and 1980s, the United States had a quite divergent approach to health promotion and determinants of health than that adopted by Canada and other European countries because of the very different structure of the health system and the emphasis placed on individualism (Lightsey, McQueen, & Anderson, 2005). As a consequence, an increased use of the language of SDH and health inequities in the United States is seen as much more recent than in countries like Canada, Great Britain, and other European countries; however, the ideas behind this language are not new in that country. When social medicine was developed as a division within academic medicine and the Yale Institute of Human Relations was set up in 1931, the expressed purpose of the institute was to “integrate medicine into research on social inequalities” (Porter, 2006, p. e39). The development of social medicine at Yale University was influenced by the need to introduce the social sciences into medicine (Viseltear, 1984). Social medicine in the United States did not have the widespread influence it had in Great Britain, mainly because of the overt political and ideological nature behind this movement; a challenge that continues to confront the adoption of the SDH as a link to or a means of reducing health inequities (Kelly, Bonnefoy, Morgan, & Florenzano, 2006). However, as Irvine et al. (2006) indicated, other developments in the United States in the 1970s such as beginning the “Healthy People” reports contributed to considering broader factors that influenced health even “act[ing] on the recommendations of the Lalonde Report and pioneer[ing] the introduction of national health targets” (p. 75).

More recently, the CDC (2010) advocated the use of an SDH approach for diseases such as HIV/AIDS, viral hepatitis, sexually transmitted diseases, and tuberculosis in order that together with individual factors, broader social and environmental factors are considered and inequities related to these diseases can be addressed. The CSDH (2008) framework on the SDH and health inequities was amended by CDC for use with “how determinants of health interact, influence inequalities, determines priorities, and target points for intervention” (p. 9). Within the American public health system there is an increased effort to advocate for the consideration of the SDH to address health inequities (Satcher, 2010). In the latest of the series on healthy people, “Healthy People 2020,” the U.S. Department of Health and Human Services (2010) states a new addition is that the concepts of the SDH and health equity will be considered from a life course approach in meeting the specified goals.

There is certainly no lack of research evidence on health disparities in the United States (Braverman et al., 2011) and the need to rethink how to approach these disparities. Rethinking approaches to disparities was placed on the agenda for the 2012 summit Nursing in 3D: Workforce Diversity, Health Disparities, and Social Determinants of Health sponsored by Health Resources and Services Administration (HRSA). The proceedings of the summit were published in a special supplement to Public Health Reports in 2014. The purpose of the summit was to enable those attending to think about health equity in the United States through the three lenses of racial/ethnicity diversity in the nursing workforce, health diversities in specific populations in the country, and the SDH; suggesting the SDH framework would be a good approach to think about diversity in the workforce and health disparities in the population (Mahony & Jones, 2013). To achieve this change two important shifts are key: first, a move to a social determinant from an individual focus and second, a move to an equity model from one based on disparity (Srinivasan & Williams, 2014); shifts that had occurred in other countries at an earlier period. Nurses in the United States are seen as potential leaders to incorporate the SDH into their work to address many of the health problems and health inequities evident in that country (Lathrop, 2013).

THE SOCIAL DETERMINANTS IDENTIFIED

There have been various attempts, locally and globally, to identify the SDH. (See Table 28.2 for some examples of the SDH identified by different authors or by country.) Sometimes this has been by broad category (structural, environmental, behavioral, and individual factors) and sometimes by a particular material or social condition (poverty). One of the first instances of identification of the SDH was in the Ottawa Charter for Health Promotion (WHO, 1986) in which a list of prerequisites for health was identified. In most of the recent conceptualizations, generally agreed upon broad categories of the SDH are grouped by level or in a hierarchy (CSDH, 2008; Marmot, 2010). At the most distal or macrolevel, from the individual or population and sometimes referred to as upstream factors (Braverman et al., 2011), are general socioeconomic, cultural, and environmental conditions (Dahlgren & Whitehead, 2006) or the socioeconomic and political context (Solar & Irwin, 2010). Next are structural factors that include social and environmental conditions (Dahlgren & Whitehead, 2006) or socioeconomic position and other axes of social differentiation (e.g., gender, ethnicity; Kelly et al., 2006; Kelly, 2010; Solar & Irwin, 2010). More proximal to those affected are social and psychological systems (Dahlgren & Whitehead, 2006) or social cohesion and social capital as bridging factors from the structural determinants to the more downstream, meso or intermediary determinants of health (Solar & Irwin, 2010). Most proximal to individuals and populations, and if included are the micro, downstream (Braverman et al., 2011), or individual lifestyle factors (Dahlgren & Whitehead) or material circumstances, behavioral and biological factors and psychosocial factors (Solar & Irwin, 2010). In Table 28.2 is a comparison of the different factors included under various conceptualizations or models of the SDH. It would be expected that these specific factors would vary from country to country, and even globally and temporally, because of the importance of a particular social structure and its context at particular times when delineating the SDH for individuals and a population, region or country, as well as the dynamic nature of social structures (Kelly et al., 2007).

MODELS USED FOR SOCIAL DETERMINANTS OF HEALTH FRAMEWORK

A number of models have been developed that are used or adapted to illustrate an SDH framework, and these come from a variety of disciplines and are informed by varying theoretical perspectives (Dunn, Masyn, Yudron, Jones, & Subramanian, 2014). Most models are influenced by a social ecological design that is presented as a series of nested, multilevel, and interrelated factors (Brofenbrenner, 1977). Using a social ecological framework recognizes the embeddedness of humans (either as individuals or populations) within their environments and the social systems that characterize these environments. Perhaps the most widely used social ecological model, especially in the academic literature, is the “Rainbow” or Social Model of Health (Dahlgren & Whitehead, 2006). The Committee on the Social Determinants of Health conceptual framework (Solar & Irwin, 2010) is also a widely used model and could be considered a social ecological model. Other models can be found in the literature as well (Dolan et al., 2005).

Rainbow or Social Model of Health

This model, described as a social ecological model, was developed by Dahlgren and Whitehead (2006) and depicts the multiple levels of the SDH influences. Figure 28.1 illustrates this model. In the center of the model are individuals with their biological and demographic factors (age, sex, and genetics). The first level is identified as “individual lifestyle factors” and these are ones that can be modified through policy and programs that address lifestyle choices such as smoking and physical activity. Likewise, the second level “social and community networks” can be either conducive to health, if the networks are present and functioning well, or not if the networks are poor or absent. The third level would be similar to what are often termed structural factors that affect health and in the model are: agriculture and food production, education, work environment, living and working conditions, unemployment, water and sanitation, health care services, and housing. The overarching level is the general socioeconomic, cultural and environmental conditions, also sometimes described as contextual factors. It is the various layers in interaction that are thought to influence human health. The Rainbow or Social Model of SDH is widely used in policy and research (Bambra et al., 2010).

 

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