Reduce the risk - Diabetes has to be tackled in everyday life
Today we know much more about what is required to prevent type 2 diabetes. The great challenge is to put this knowledge into everyday practice.
Type 2 diabetes - or adult-onset diabetes - is one of the most common diseases in Sweden. There are no nationwide studies at present that show how many people have type 2 diabetes, but estimates put the number at around 400 000. This figure takes account of the unreported cases known to exist. It has been shown, for example, that two-thirds of those who suffer a first heart attack are diabetics, and half of these have no idea that they have diabetes!
To develop type 2 diabetes a person has to have a certain genetic predisposition, which together with the way we live our lives - whether or not we eat too much, take too little exercise, smoke, become stressed and so on - determines whether we become ill or not. A number of studies have now identified various risk factors and what we can do ourselves to prevent the disease from occurring or to slow down its progression when it has been established that we have a preliminary stage of diabetes. Most of these factors are related to lifestyle and lead to reduced insulin sensitivity, that is to say the effectiveness of insulin deteriorates.
The body can compensate for this with increased release of insulin from the beta cells in the pancreas, but this does not succeed if the individual has inherited a predisposition to diabetes that limits this option. A first sign of diabetes starting to develop is that the blood sugar (glucose) is slightly too high after a meal - this is known as reduced glucose tolerance.
"In many parts of the health service there used to be an attitude that slightly raised blood sugar is probably not all that dangerous. I hope that this attitude is now changing. Reduced glucose tolerance, which shows that a disorder has started to develop, can also result in serious complications if it is not treated," says Claes-Göran Östenson, professor at Karolinska Institutet and head of the Diabetes Prevention Unit at Karolinska University Hospital, Solna.
In an extensive epidemiological study in Greater Stockholm over a period of ten years, Professor Östenson has clarified the prevalence of type 2 diabetes in middle-aged people, whether more people are developing the disease and whether there are any differences between women and men. He has also looked at both risk factors and health factors that have a significant bearing on whether someone develops the disease.
"We found that a small increase had taken place among men, while the opposite situation applied to women. We also found that in the 4666 age group there were twice as many men as women with type 2 diabetes. The results were in good agreement with other major studies carried out in Sweden, which likewise did not point to any marked increase in type 2 diabetes," says Professor Östenson.
It is important to detect the first signs of preliminary stages of type 2 diabetes early. There ought therefore to be more active testing of groups at risk, Professor Östenson feels. This applies for example to women who have had gestational diabetes, certain immigrant groups in which diabetes is known to be more common, overweight individuals and those with a family history of diabetes.
Around half of those diagnosed already have signs of complications. These are changes both in the larger blood vessels (which lead to heart attacks and stroke) and in the small blood vessels, the capillaries. Changes in the small blood vessels affect the retina, kidneys and nerves, for instance. Many factors contribute to these changes. Raised blood sugar levels lead to disturbance of the blood clotting system, and high blood lipids - common in diabetics - adversely affect the walls of blood vessels. Many diabetics are overweight, and the fatty acids produced by the abdominal fat are particularly dangerous. They do not just affect the cells in the walls of the blood vessels, they also have a negative impact on insulin production and the effectiveness of insulin.
"It would be useful to be able to identify individuals who are at risk of developing diabetes at an early stage, and we are therefore trying to find markers that can predict the risk. We are looking, for instance, at various types of hormones and cytokines, substances in the immune system."
Professor Östenson and his fellow researchers are also interested in investigating which genes play a key role in type 2 diabetes. Studies have recently shown that several of the genetic changes these patients show can be linked to poorer functioning of the insulin-producing beta cells in the pancreas. Around ten different genes are involved. Professor Östenson hopes that continued studies might lead to even more effective drugs in the longer term.
How to reduce the risk of type 2 diabetes
- Aim for normal weight (being overweight increases the risk 5 times)
- Stay physically active (physical exercise can more than halve the risk)
- Do not smoke (smoking increases the risk 2-3 times)
- Try to avoid stress (stress increases the risk 2-3 times)
- Drink five to six cups of coffee a day (may reduce the risk by 70 per cent)
It is particularly important to think about this if there is diabetes in your family, as hereditary factors play a significant role. If both your patients have type 2 diabetes, for example, the risk of being affected yourself is almost nine times higher. If, in addition, you are severely overweight, the risk is 25-30 higher.
First published in Medical Science, issue 1, 2009