Diabetes is one of the most significant non-communicable diseases globally, and is also a leading cause of mortality. In the United States for example, where there are an estimated 26 million diabetics, diabetes was a contributory factor to around 230 000 deaths in 2007. In Europe, an estimated 55 million people live with diabetes. Across the world, the population of diabetics is expected to rise from 285 million in 2010 to 438 million by 2030 (IDF, 2009) (see also Indicator 1.10, "Diabetes prevalence and incidence" ).

Diabetes is implicated in cardiovascular disease, hypertension, kidney disease and lower limb amputation. It is also the leading cause of blindness in industrialised countries and the most common cause of end-stage renal disease in the United States, Europe, and Japan. Furthermore, studies have shown that people who have diabetes are more likely to have depression and find it more difficult to follow treatment guidelines (Mezuk et al., 2008; Egede, 2004).

Major risk factors for diabetes include being overweight or obese, physically inactive, having familial history of diabetes, having high blood pressure and having a history of cardiovascular disease. The multi-centre Diabetes Prevention Program (DPP, 2002) showed that modest weight loss and dietary changes can delay or even prevent the onset of diabetes. Researchers in the DPP trial also found that intensive counselling on effective diet, exercise, and behaviour modification reduced the risk of developing diabetes by almost 60%. This finding applied to all ethnic groups, and for both males and females. These lifestyle changes had their greatest impact on older age groups where the interventions led to a 70% reduction in risk. These findings underline the importance of having diabetes prevention and management programmes embedded in primary care settings.

Figure 5.2.1 shows that there are large variations in admission rates for uncontrolled diabetes across OECD countries. Austria, Hungary, Korea and Mexico have rates that are more than double the OECD average. Spain, Israel, Australia and New Zealand have very low admissions rates for uncontrolled diabetes. Despite having high disease prevalence, Canada has moderately low admission rates. This may be indicative of the impact of Canada's Integrated Strategy on Health Living and Chronic Disease and the Canadian Diabetes Strategy (PHAC, 2005). Male admission rates for uncontrolled diabetes are around 20% higher than females, though several countries, notably Finland, Sweden and Denmark, have considerably higher male admission rates compared to females.

Austria has taken steps to improve diabetes care via its disease management programme (DMP) which was implemented in 2007. Findings from a recent study showed that the Austrian diabetes DMP improved process quality and enhanced weight loss, but did not significantly improve diabetes control (Sönnichsen et al., 2010). The same research also noted that quality depends more on the care offered by a specific family physician than on the widespread implementation of a programme.

In Korea, the high rate of admissions can only be partly explained by higher diabetes prevalence related to changing lifestyle brought about by recent economic development (Cho, 2010). It is also linked to a less developed primary care infrastructure (Chun et al., 2009).

Figure 5.2.2 shows that uncontrolled diabetes admission rates do not appear to be strongly correlated with diabetes prevalence, with some countries such as Canada, Portugal and the United States having high prevalence rates but low admission rates. Conversely, Finland, Sweden and Denmark have lower prevalence rates but higher admission rates. The absence of any meaningful correlation suggests that factors other than disease "volume" are at play when explaining hospital admissions.