The social determinants of diabetes and the challenge of prevention

The UN Millennium Development Goals (set in 2000 and providing targets to be met by 2015) make no mention of diabetes or related non-communicable diseases (NCDs), reflecting the misconception that these are diseases of affluence (Section 4.4). In fact, diabetes and related NCDs should be key targets for reducing health inequity globally and within low- and middle-income countries as there are powerful underlying societal factors behind the diabetes epidemic. 1 

In high-income countries, type 2 diabetes tends to be more prevalent in the less well off. Diabetes is often more common in the wealthier parts of the population of low-income countries, but there is also evidence that in some middle-income countries, it is now more common in poorer sections of society. 2  However, focusing only on which socioeconomic group has the most diabetes obscures the fact that even in low-income countries, diabetes is already very common in the poorest sections of society—especially in urban areas, where one in six, or more, adults has diabetes.

Spending on care

In countries where access to healthcare is limited, and people often need to pay for their own care, it is the poor on whom diabetes has the greatest social and economic impact. For example, in Chennai, India, people from middle- or low-income groups can spend a sixth to a quarter of their income on diabetes care. 3 

The obesogenic environment

The underlying determinants of diabetes are the same the world over. Economic development is associated with increasingly ‘obesogenic environments’ characterized by decreased physical activity and increasing access to energy-rich diets. Globalization plays a large part in these changes, for example, transnational food corporations are one of the major investors in low- and middle-income countries, 4  as the profits to be gained from food processing and retailing are huge.

Figure 4.6 outlines key factors in the determinants and consequences of diabetes, according to the framework used by the World Health Organization book on equity, social determinants, and public health programmes. 1  This demonstrates the way that underlying societal factors are driving the diabetes epidemic in all countries. At each level there are social gradients resulting in worse outcomes and consequences for those who are disadvantaged. For example, the poor are more likely to be exposed to an ‘obesogenic environment’ and more likely to have worse health outcomes. In addition, poor women are more vulnerable to poor nutrition during pregnancy which can raise their child’s vulnerability to the risk factors for diabetes later in life.

Challenges of prevention

There is a great deal of interest in approaches to the prevention of type 2 diabetes that target people who are at high risk.  5   6  However, targeting individuals at high-risk is at best likely to have a moderate impact on the prevalence of type 2 diabetes. There are two reasons for this. Firstly, it is difficult to translate approaches from complex and well-resourced research studies into the ‘real world’, including being able to find and recruit people who are at high-risk and deliver effective prevention. Secondly, a substantial proportion of diabetes will arise in people who are not identified as high-risk, and who would not, therefore, be recruited for such preventive interventions.

The real challenge is to tackle the underlying determinants of type 2 diabetes globally, which, put simply, means modifying environments to make them less obesogenic. This challenge is as great if not greater than reducing tobacco consumption. Modifying the obesogenic environment is likely to require a broad range of policy measures across multiple sectors.

 

1: Whiting D, Unwin N, Roglic G. Diabetes: equity and social determinants. In Blas E, Kurup A, editors. Equity, social determinants and public health programmes. World Health Organization; 2010. p77-94.

2: Goldstein J, Jacoby E, del Aguila R, et al. Poverty is a predictor of non-communicable disease among adults in Peruvian cities. Prev Med 2005; 41 (3-4): 800-806.

3: Shobhana R, Rao PR, Lavanya A, et al. Expenditure on health care incurred by diabetic subjects in a developing country--a study from southern India. Diabetes Res Clin Pract 2000; 48 (1): 37-42.

4: Hawkes C. The role of foreign direct investment in the nutrition transition. Public Health Nutr 2005; 8 (4): 357-365.

5: Knowler WC, Connor EB, Fowler SE, et al. Reduction in the incidence of type 2 diabetes with lifestyle intervention or metformin 2002; 346 (6): 393-403.

6: Lindström J, Louheranta A, Mannelin M, et al. The Finnish Diabetes Prevention Study (DPS): Lifestyle intervention and 3-year results on diet and physical activity. Diabetes Care 2003; 26 (12): 3230-3236.