Socioekonomiska aspekter av diabetes och kardiovaskulär sjukdom

Abstract

Four hundred million people in the world have diabetes. The incidence of type 1 diabetes has increased steadily in the last few decades and it is now the second most common chronic disease of childhood. Type 2 diabetes develops in adults and older individuals with unhealthy dietary patterns, overweight and sedentary habits.

It is well known that socioeconomic status has a substantial impact on health and longevity. The effect of socioeconomic status has been examined thoroughly in cardiovascular medicine. When it comes to diabetes, however, there are important gaps in knowledge. Socioeconomic status includes primarily income, education, ethnicity and occupation. These variables may serve as easily accessible risk markers.

The present thesis is based on the Swedish National Diabetes Register (NDR). The NDR includes the majority of all individuals (aged 18 years and older) with diabetes. We examined how socioeconomic status affects survival, risk factor control and the risk of developing heart failure. We also examined the incidence of type 1 diabetes in people aged 34 and younger.

We show that the incidence of type 1 diabetes in 15–34 year-olds is two to three times as high as previously reported. Our analyses show that the Prescribed Drug Register is probably the gold standard for monitoring the incidence of type 1 diabetes.

Low income and educational level was associated with two to three times as great a risk of serious cardiovascular events and death in type 1 diabetes. Being male, divorced, single or widowed was also associated with substantially higher risk of adverse outcomes. Controlling for conventional risk factors and confounders did not eliminate the disparities.

Risk factor control in type 1 diabetes has improved in the last two decades. However, the improvements have been less pronounced among individuals with low socioeconomic status. Some of the socioeconomic gaps have widened over time. For example, individuals with low education have not improved their glycaemic control (HbA1c) during the period 1996 to 2014, whereas those with high educational level lowered their HbA1c by 4.0 mmol/mol.

Non-Western immigrants to Sweden develop type 2 diabetes a decade earlier than native Swedes. Immigrants have higher HbA1c, greater risk of therapy failure and higher probability of developing albuminuria than native Swedes. Ethnicity has a greater impact on glycaemic control than income or educational level.

There are ethnic differences in the risk of developing heart failure among individuals with type 2 diabetes. Individuals from South Asia appear to be at greater risk of developing heart failure, whereas those from Latin America are at lower risk, than native Swedes. Individuals with low income had 70% higher risk of developing heart failure, as compared with individuals with high income.

Ethnicity and socioeconomic status should be routinely considered in clinical management if diabetes care is to improve. These variables are easily accessible risk markers. Stringent risk factor control may be the most effective means of reducing these disparities.