Type 2 Diabetes
Type 2 diabetes occurs mainly in people aged over 40. The first-line treatment is diet, weight control and physical activity. If the blood glucose level remains high despite these measures, then tablets to reduce the blood glucose level are usually advised. Insulin injections are needed in some cases. Other treatments include reducing blood pressure if it is high, lowering high cholesterol levels.
What is diabetes?
Diabetes mellitus (just called diabetes from now on) occurs when the level of glucose (sugar) in the blood becomes higher than normal. There are two main types of diabetes - type 1 diabetes and type 2 diabetes.
Understanding blood glucose and insulin
After you eat, various foods are broken down in your gut into sugars. The main sugar is called glucose which passes through your gut wall into your bloodstream. However, to remain healthy, your blood glucose level should not go too high or too low.
So, when your blood glucose level begins to rise (after you eat), the level of a hormone called insulin should also rise. Insulin works on the cells of your body and makes them take in glucose from the bloodstream. Some of the glucose is used by the cells for energy, and some is converted into glycogen or fat (which are stores of energy). When the blood glucose level begins to fall (between meals), the level of insulin falls. Some glycogen or fat is then converted back into glucose which is released from the cells into the bloodstream.
Insulin is a hormone that is made by cells called beta cells. These are part of little islands of cells (islets) within the pancreas. Hormones are chemicals that are released into the bloodstream and work on various parts of the body.
What is type 2 diabetes?
With type 2 diabetes, the illness and symptoms tend to develop gradually (over weeks or months). This is because in type 2 diabetes you still make insulin (unlike type 1 diabetes). However, you develop diabetes because:
- You do not make enough insulin for your body's needs; OR
- The cells in your body do not use insulin properly. This is called insulin resistance. The cells in your body become resistant to normal levels of insulin. This means that you need more insulin than you normally make to keep the blood glucose level down; OR
- A combination of the above two reasons.
Type 2 diabetes is much more common than type 1 diabetes.
What is type 1 diabetes?
In type 1 diabetes the beta cells in the pancreas stop making insulin. The illness and symptoms develop quickly (over days or weeks) because the level of insulin in the bloodstream becomes very low. Type 1 diabetes used to be known as juvenile, early-onset, or insulin-dependent diabetes. It usually first develops in children or in young adults. Type 1 diabetes is treated with insulin injections and diet.
Who gets type 2 diabetes?
Type 2 diabetes used to be known as maturity-onset, or non-insulin-dependent diabetes. It develops mainly in people older than the age of 40 (but can also occur in younger people. Type 2 diabetes is now becoming more common in children and in young people.
It also tends to run in families. It is around five times more common in South Asian and African-Caribbean people (often developing before the age of 40 in this group).
Other risk factors for type 2 diabetes include:
- Having a first-degree relative with type 2 diabetes. (A first-degree relative is a parent, brother, sister, or child.)
- Being overweight or obese.
- Having a waist measuring more than 31.5 inches (80 cm) if you are a woman or more than 37 inches (94 cm) if you are a man.
- Having impaired glucose tolerance. (Impaired glucose tolerance is when your blood glucose levels are higher than normal but not high enough to have diabetes.)
- Having diabetes or impaired glucose tolerance when you were pregnant.
What are the symptoms of type 2 diabetes?
As already mentioned, the symptoms of type 2 diabetes often come on gradually and can be quite vague at first. Many people have diabetes for a long period of time before their diagnosis is made.
The four common symptoms are:
- Being thirsty a lot of the time.
- Passing large amounts of urine.
- Weight loss.
The reason why you make a lot of urine and become thirsty is because glucose leaks into your urine which pulls out extra water through the kidneys.
As the symptoms may develop gradually, you can become used to being thirsty and tired and you may not recognise that you are ill for some time. Some people also develop blurred vision and frequent infections, such as recurring thrush. However, some people with type 2 diabetes do not have any symptoms if the blood glucose level is not too high. But, even if you do not have symptoms, you should still have treatment to reduce the risk of developing complications.
How is diabetes diagnosed?
A simple dipstick test may detect glucose in a sample of urine. However, this is not sufficient to diagnose diabetes definitely. Therefore, a blood test is needed to make the diagnosis. The blood test detects the level of glucose in your blood. If the blood glucose level is high then it will confirm that you have diabetes. Some people have to have two samples of blood taken and you may be asked to fast (have nothing to eat or drink, other than water, from midnight before your blood test is performed).
In many cases diabetes is diagnosed during a routine medical or when tests are done for an unrelated medical condition.
What are the possible complications of diabetes?
Short-term complication - a very high blood glucose level
This is not common with type 2 diabetes. It is more common in untreated type 1 diabetes when a very high level of glucose can develop quickly. However, a very high glucose level develops in some people with untreated type 2 diabetes. A very high blood level of glucose can cause dehydration, drowsiness and serious illness which can be life-threatening.
If your blood glucose level is higher than normal over a long period of time, it can gradually damage your blood vessels. This can occur even if the glucose level is not very high above the normal level. This may lead to some of the following complications (often years after you first develop diabetes):
- Atheroma (furring or hardening of the arteries). This can cause problems such as angina, heart attacks, stroke and poor circulation.
- Kidney damage which sometimes develops into kidney failure.
- Eye problems which can affect vision (due to damage to the small arteries of the retina at the back of the eye).
- Nerve damage.
- Foot problems (due to poor circulation and nerve damage).
- Impotence (again due to poor circulation and nerve damage).
Other rare problems.
The type and severity of long-term complications vary from case to case. You may not develop any at all. In general, the nearer your blood glucose level is to normal, the less your risk of developing complications. Your risk of developing complications is also reduced if you deal with any other risk factors that you may have, such as high blood pressure.
Complications of treatment
Hypoglycaemia (which is often called a hypo) occurs when the level of glucose becomes too low, usually under 4 mmol/L. People with diabetes who take insulin and/or certain diabetes tablets are at risk of having a hypo. A hypo may occur if you have too much diabetes medication, have delayed or missed a meal or snack, or have taken part in unplanned exercise or physical activity.
Symptoms of hypoglycaemia include: trembling, sweating, anxiety, blurred vision, tingling lips, paleness, mood change, vagueness or confusion. To treat hypoglycaemia you should take a sugary drink or some sweets. Then eat a starchy snack such as a sandwich.
Note: hypoglycaemiacan not occur if you are treated with diet alone.
What are the aims of treatment?
Although diabetes cannot be cured, it can be treated successfully.
Treatment aim 1 - keeping your blood glucose level at normal levels
How is the blood glucose level monitored?
The blood test that is mainly used to keep a check on your blood glucose level is called the HbA1c test. This test is commonly done every 2-6 months by your doctor or nurse.
The HbA1c test measures a part of the red blood cells. Glucose in the blood attaches to part of the red blood cells. This part can be measured and gives a good indication of your average blood glucose level over the preceding 1-3 months.
Treatment aims to lower your HbA1c to below a target level. Ideally, it is best to maintain HbA1c to less than 6.5%. However, this may not always be possible to achieve and your target level of HbA1c should be agreed between you and your doctor. If your HbA1c is above your target level then you may be advised to step up treatment (for example, to increase a dose of medication) to keep your blood glucose level down.
Some people with diabetes check their actual blood glucose level regularly with a blood glucose monitor. If you are advised to do this then your doctor or nurse will give you instructions on how to do it.
Lifestyle - diet, weight control and physical activity.
Lifestyle changes are an essential part of treatment for all people with type 2 diabetes, regardless of whether or not you take medication.
You can usually reduce the level of your blood glucose and HbA1c if you:
- Eat a healthy and balanced diet.
- Lose weight if you are overweight.
- Do some physical activity regularly
- Physical activity also reduces your risk of having a heart attack or stroke.
Many people with type 2 diabetes can reduce their blood glucose (and HbA1c) to a target level by the above measures. However, if the blood glucose (or HbA1c) level remains too high after a trial of these measures for a few months, then medication is usually advised.
There are various medicines that can reduce the blood glucose level. Different ones suit different people.
Insulin is needed in some cases if the above treatments do not work well enough. You cannot take insulin by mouth, as it is destroyed by the digestive juices in the gut. Insulin may be given in addition to taking tablets.
Treatment aim 2 - to reduce other risk factors
You are less likely to develop complications of diabetes if you reduce any other risk factors.
Keep your blood pressure down
It is very important to have your blood pressure checked regularly. The combination of high blood pressure and diabetes is a particularly high risk factor for complications.
If you smoke - now is the time to stop
Smoking is a high risk factor for complications.
You will usually be advised to take a drug to lower your cholesterol level. This will help to lower the risk of developing some complications such as heart disease, peripheral vascular disease and stroke.
Treatment aim 3 - to detect and treat any complications promptly
- Most GP surgeries and hospitals have special diabetes clinics. Doctors, nurses, dietitians, chiropodists, optometrists and other healthcare workers all play a role in giving advice and checking on progress. Regular checks may include:
- Checking levels of blood glucose, HbA1c, cholesterol and blood pressure.
- Ongoing advice on diet and lifestyle.
- Checking for early signs of complications, for example:
- Eye checks - to detect problems with the retina (a possible complication of diabetes) which can often be prevented from getting worse. Glaucoma is also more common in people with diabetes and can usually be treated.
- Urine tests - which include testing for protein in the urine, which may indicate early kidney problems.
- Foot checks - to help to prevent foot ulcers.
- Other blood tests - these include checks on kidney function and other general tests.
- It is important to have regular checks, as some complications, particularly if detected early, can be treated or prevented from getting worse.
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