Type 2 diabetes (diabetes mellitus) is a metabolic disease that causes sugar to build up in the bloodstream. The severity of diabetes can vary quite a bit: Some people only have to make minor changes to their lifestyle after they are diagnosed. Just losing a little weight and getting some more exercise may be enough for them to manage their diabetes. Other people who have type 2 diabetes need more permanent therapy that involves taking tablets or insulin. It is then especially important to have a good understanding of the disease and know what you can do to stay healthy.
There are two main types of diabetes. Type 1 diabetes usually develops in childhood or at a young age. Type 1 diabetes is a result of a damaged pancreas that leaves the organ producing either very little insulin or none at all.
Type 2 diabetes is quite different. It used to be referred to as “adult-onset” diabetes because it is often diagnosed later in life. In type 2 diabetes, it becomes increasingly difficult for the body’s cells to absorb and use the insulin. Type 2 diabetes is much more common than type 1 diabetes. About 90 % of people who have diabetes have type 2 diabetes.
If type 2 diabetes goes untreated, blood sugar levels stay high permanently. They may not always notice it at first. Type 2 diabetes can develop gradually over several years without any noticeable symptoms. Blood sugar levels that are continuously too high may cause the following symptoms:
- Feeling very thirsty
- Frequent urination
- Tiredness and listlessness
If someone has extremely high blood sugar levels, they may feel confused and drowsy or even lose consciousness (diabetic coma).
Our metabolism converts food into energy for the body to use. One of the things our bodies need for this process is insulin.
Insulin is a hormone, a chemical that the body uses to send messages. Insulin is made by the pancreas. After you eat the sugar levels in your blood rise and it is released into the bloodstream. It then makes the cells in the liver and in muscle tissue absorb sugar from the blood. If insulin metabolism is not working properly, the sugar (glucose) in our blood cannot be used in the right way. This causes blood sugar levels to rise. If blood sugar levels are too high it is called hyperglycemia.
In people who have type 2 diabetes the pancreas does actually produce enough insulin, but it no longer has an effect on the body's tissue and cells. This is what doctors refer to as “insulin resistance.” The pancreas can compensate for this temporarily by producing more insulin. But at some point the pancreas will not be able to keep up, and then blood sugar levels start to rise.
There are different factors that can favor the development of type 2 diabetes:
- Being overweight and not getting enough physical exercise
- A low-fiber, high-fat and sugary diet
- Some medications that affect the body’s sugar metabolism
- Genetic factors: Some families are more likely to develop type 2 diabetes.
People who have type 2 diabetes are also at greater risk of developing cardiovascular diseases such as heart attack, stroke or problems with circulation in their legs and feet (peripheral artery disease, PAD). These are the “macrovascular” complications of diabetes. “Macrovascular” means that these complications affect the larger blood vessels. This risk is especially high in people who also have high blood pressure.
If there is too much sugar in the blood for years at a time, the smaller blood vessels in the eyes, nerves and kidneys can be damaged. These are called the microvascular complications of diabetes. “Microvascular” means that the smaller blood vessels are affected. The medical names for these kinds of complications are retinopathy (damage to the retina), neuropathy (nerve damage), and nephropathy (kidney damage). The later someone develops type 2 diabetes, the less likely it is that they will develop these kinds of problems.
Because type 2 diabetes develops so gradually, people will at first usually only have minor symptoms or no symptoms at all. High blood sugar levels in the blood or urine are often first detected during a routine check-up. If you are thought to have type 2 diabetes your doctor will first ask about any symptoms and other conditions that you may have. You will then also have a physical examination and your blood sugar levels will be tested. To check your blood sugar levels before your first meal and over the course of a day, several blood samples will be taken and then analyzed in the laboratory. The HbA1c value will also be measured: That reading shows the average blood sugar level over the last two to three months.
If blood sugar levels are high enough to be causing typical symptoms, sugar can usually be detected in the urine as well. Easy-to-use test strips to test for sugar in the urine are available from pharmacies and doctor's practices in Germany and many other countries.
There are numerous recommendations for preventing type 2 diabetes. The main ones have to do with lifestyle: eating a balanced diet, getting enough exercise and watching your weight.
Diet changes or more exercise can actually delay diagnosis by a few years for people at a greater risk of developing the condition. But it is still not clear whether these kinds of changes can prevent diabetes altogether, as some experts hope.
There are a number of factors that influence whether treatment for type 2 diabetes is a good idea and worthwhile: They include age, physical condition, other diseases, lifestyle and the individual goals of the person who has diabetes.
Sometimes just changing your lifestyle can have a positive effect: Losing weight and getting more exercise can make insulin more effective and lower blood sugar levels. Quitting smoking helps to reduce the risk of cardiovascular disease. Some people can manage the condition and the other associated risks just by making these kinds of adjustments to their habits.
If people who are very overweight (obese) are unable to lose weight, stomach reduction surgery may also be an option.
Some people depend on medication to regulate their blood sugar levels. Some people take tablets, while others inject insulin or medication called incretin mimetics (hormone-like substances that are designed to increase the body's insulin production). It is also possible to combine tablets and injections. The most common medications used to treat type 2 diabetes (antidiabetic drugs) are metformin and sulfonylureas. Newer antidiabetic drugs are also available – but there are still many unanswered questions about their effects.
Depending on what other symptoms and illnesses a person has, there are different kinds of medication available that can help to relieve specific symptoms or lower particular risks. For example, many people who have type 2 diabetes also have high blood pressure.
The main medications that can lower the risk of cardiovascular disease
- lower blood pressure (antihypertensives),
- prevent blood clotting (ASA), or
- reduce cholesterol levels (statins).
There are some things that people who have type 2 diabetes can do to get by without medication. The most important thing is to lose at least a little weight – even though that may be difficult to achieve in practice. Even just a little more physical activity can have a positive effect, for example getting into the habit of walking more often.
If that is not enough, medication is an option, but that then has to be taken regularly over a long period of time. It can be difficult to get used to the idea of taking medication for the rest of your life – especially if you do not feel ill and do not notice any immediate benefit. Managing type 2 diabetes treatment can be a real challenge, especially at first. But having the facts about diabetes can make dealing with the condition a normal part of your daily routine that need not affect quality of life.
No matter what type of treatment you end up choosing, the key to managing diabetes is understanding the disease and knowing what you can do to help protect your own health. It is also important to have the support of your doctor and other specialists, including diabetes and diet consultants, and foot specialists.
In Germany there is also a wide range of different services for individual counseling and support if you are ill. Many of these offers vary greatly depending where they are based, and they are not always easy to find. A list of points of contact can help you to locate and make use of these services.
Another option is taking part in a “disease management program” where diabetes specialists offer courses about the disease, counseling services and comprehensive medical care.
Nationale Versorgungsleitlinie. Therapie des Typ-2-Diabetes. Version 1. August 2013.
American Diabetes Association. Standards of medical care in diabetes--2014. Diabetes Care 2014; 37 Suppl 1: S14-80.
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