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Social Determinants of Health ( SDOH )
The World Health Organization defines SDOH as “… the circumstances in which people are born , grow up , live , work and age , and the systems put in place to deal with illness . These circumstances are in turn shaped by a wider set of forces : economics , social policies , and politics ” ( WHO Health Commission on Social Determinants of Health , 2008 , para . 6 ). This definition , in itself , is broad and its breadth tempts some to dismiss it . However , there are several important aspects of the definition that are forward looking and consistent with a growing body of literature , suggesting that this definition can help clarify a necessarily broad area of intellectual and pragmatic import . First , there is a large research base , much of it coming from social epidemiology and related fields , that supports the importance of the factors — even if many — mentioned in the definition for the production of population health . Second , the SDOH perspective explicitly adopts a life course framework , rapidly gaining credence as a viable lens through which we can consider the production of multiple dimensions of multiple population health ( Koenen , Rudenstine , Susser , & Galea 2013 ; Yoav & Kuh , 2002 ), and third , by including “ economics , social policies , and politics ,” as shapers of life circumstances it considerably broadens the view of what causes some people or groups to be sick while other remain well ( Evans , Barer , & Marmor 1994 ; Evans , Whitehead , Diderichsen , Bhuia , & Wirth , 2001 ; Galea 2007 ; Kaplan 1995 ).
This comprehensive “ cells-to-society ” framework for understanding the SDOH , therefore suggests the need for a multi-level , multi-scale , and dynamic life course perspective brings . While we suggest here that this is indeed the right framing for the SDOH , this approach also brings with it many analytic and conceptual challenges to the dominant reductionist view . Fortunately , as will be described below , they are challenges that systems science and complex systems approaches are particularly well-suited to address , making these approaches , perhaps inexorably , a core component of SDOH research and practice in coming decades . We illustrate this first by focusing on two examples .
Two SDOH
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SEP , a more inclusive term than “ socioeconomic status ,” is one of the cardinal social determinants of health , with its impact felt on most health outcomes , across the life span , and over time and place ( Braveman , Cubbin , Egerter , Williams , & Pamuk , 2010 ; Haan , Kaplan , & Syme 1989 ; Kaplan 2009 ; Lynch , Kaplan , & Shema , 1997 ; Pamuk , Makuc , Heck , Reuben , & Lochner , 1998 ). There are many dimensions to SEP , but by far the most attention has been given to income and education . Many studies have established a relationship between income and risk of death . For example , in the United States , data from National Longitudinal Mortality Study ( NLMS ), based on 7.6 million person years of follow-up over 10 years ( see Figure 1 ), there is a strong and nonlinear gradient between income and risk of death ( Wolfson , Kaplan , Lynch , Ross , & Backlund , 2000 ); this has also been found by others ( Dowd et al ., 2011 ). Recent work by Kaplan and colleagues ( in progress ) suggests that the inflection point has been moving rightward , so that now for roughly 50 % of the population there are increasing returns on health from increasing income .
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