Type 2 diabetes

Published by Bupa’s Health Information Team, June 2011.

This factsheet is for people who have type 2 diabetes, or who would like information about it including the symptoms, causes and treatments.

Type 2 diabetes is a lifelong condition in which the body can’t control levels of glucose in the blood. It develops when the body can’t make enough insulin or doesn't respond to it. Type 2 diabetes is sometimes called non-insulin dependent diabetes.

Animation - how type 2 diabetes develops

           A Flash plug-in is required to view this animation.

About type 2 diabetes

Around 2.6 million people in the UK have been diagnosed with diabetes. About nine in 10 of these people have type 2 diabetes. It usually affects people over the age of 40, but can develop at any age. People of African-Caribbean or South Asian origin are more likely to develop type 2 diabetes. It usually affects them earlier in life, from about the age of 25. Type 2 diabetes is becoming more common, particularly in children.

Type 2 diabetes develops when your body can’t produce enough insulin or if your body doesn’t respond to insulin as it should. Insulin regulates the level of glucose in your blood. Glucose is a simple form of sugar found in foods and sugary drinks. It’s absorbed by your body as a natural part of digestion and is carried around your body in your blood. When glucose reaches your body tissues, such as muscle cells, it's absorbed and converted into energy.

Insulin is secreted into your blood by your pancreas, which is a gland located behind your stomach. If your cells don't respond properly to insulin, it can cause glucose to build up in your blood. This is called insulin resistance. If this happens, your pancreas needs to produce more and more insulin to overcome the resistance and control your blood glucose levels.

Types of diabetes

There are two main types of diabetes: type 1 and type 2.

There are about two million people in the UK who have diabetes. Type 2 diabetes is the common form, affecting nine out of every 10 people with diabetes.

Symptoms of type 2 diabetes

Many people with type 2 diabetes have no obvious symptoms. It's often discovered during a routine medical check-up with your GP.

If you do have symptoms of type 2 diabetes, you may:

• pass more urine than usual
• be constantly thirsty
• have unexplained weight loss
• be extremely tired
• have blurred vision
• have itchy skin around your genitals or get regular infections, such as thrush
• notice that wounds such as cuts heal slowly

If you have any of these symptoms, see your GP.

Initially, some people find they don’t have any symptoms. So if you think you may be at risk of type 2 diabetes, speak to your GP about having a screening blood test.

Complications of type 2 diabetes

If type 2 diabetes isn’t diagnosed or controlled properly, you can develop blood glucose levels that are either too high (hyperglycaemia) or too low (hypoglycaemia).

Hyperglycaemia

If type 2 diabetes is poorly controlled or you get an infection, glucose can build up in your blood and rise to high levels. This can cause you to:

• be thirsty
• pass urine excessively
• have blurred vision
• feel tired

Very rarely, if you become dehydrated and your blood glucose rises to very high levels, you can develop a condition called hyperosmolar hyperglycaemic state. This can cause you to become drowsy and potentially unconscious. Hyperosmolar hyperglycaemic state is a medical emergency and needs to be treated in hospital.

In the long-term, uncontrolled high blood glucose levels can increase your risk of:

• kidney failure
• blindness
• nerve damage
• heart disease
• stroke

Hypoglycaemia

Sometimes, if your medication is too strong or you miss a meal, your blood glucose levels can become too low (hypoglycaemia). This only happens if you’re taking certain medicines such as gliclazide (or others of the same type), repaglinide or insulin (of any type).

If your blood glucose is low, you may go pale, feel sweaty and become confused. If you develop hypoglycaemia, it’s important to eat or drink something containing glucose, for example fruit juice or some sweets.

Causes of type 2 diabetes

There are several risk factors that make you more likely to develop type 2 diabetes, including if you:

• are overweight or obese – in particular, if you’re an 'apple shape' with lots of fat around your abdomen (tummy)
• have a close family member with the condition
• are of African-Caribbean or South-Asian origin
• are over 40 – your risk increases with age
• have high blood pressure or have had a heart attack or stroke
• don’t exercise regularly
• have severe mental health problems
• are a woman and have polycystic ovary syndrome and are overweight
• are a woman and have had diabetes that developed during pregnancy (gestational diabetes)

If you have a condition such as impaired glucose tolerance or impaired fasting glycaemia, this means the level of glucose in your blood is naturally higher than normal and you’re more likely to develop type 2 diabetes.

Diagnosis of type 2 diabetes

Your GP will ask about your symptoms and examine you. He or she may also ask about your medical history.

You may need to have some of the following tests.

• Urine test. You will need to give a sample to be tested for glucose.
• Fasting blood glucose test. You will have a sample of blood taken from your arm to test for glucose. You will need to fast overnight before having this test. You may have this with a glycosylated haemoglobin (HbA1C) test. HbA1C is a protein that is produced when you have high blood glucose levels over a long period of time.
• Glucose tolerance test. This may be needed if your fasting blood glucose test is borderline. It measures how your blood glucose level changes over time after you have a sugary drink. You will need to fast overnight before having this test.

Treatment of type 2 diabetes

There isn't a cure for type 2 diabetes but it can be controlled. Some people can control their condition with lifestyle changes alone. Others need to take medicines or use insulin injections.

Self-help

By making the following lifestyle changes, you can help control your blood glucose levels.

• Eat a healthy balanced diet with regular meals, three times a day. Include carbohydrates, such as pasta or potatoes in each meal.
• Aim to do 150 minutes of moderate exercise over a week in bouts of 10 minutes or more. This will help you to stay a healthy weight and control your blood glucose levels.
• Only drink alcohol in moderation and stick within the recommended limits.
• If you smoke, give up. Smoking is unhealthy for everyone, but it's especially important to stop if you have diabetes because you already have an increased risk of developing circulatory problems and cardiovascular disease.

Oral medicines

If lifestyle changes alone don’t keep your blood glucose levels under control, you may be prescribed medicines. Some examples are listed below.

• Metformin works by reducing the amount of glucose that gets released into your bloodstream from your liver. It also improves the way glucose is used by your muscles.
• Gliclazide, glipizide, glimepiride and tolbutamide help your pancreas to produce more insulin.
• Repaglinide and nateglinide also help your pancreas to produce more insulin, but work more quickly and last for a shorter time.
• Acarbose lowers your blood glucose by slowing down the rate at which some carbohydrates are absorbed by your body.
• Pioglitazone reduces your body's resistance to insulin.
• Sitagliptin, saxagliptin and vildagliptin help your body to produce more insulin at mealtimes.

These medicines are usually taken between one and three times a day.

Injections

You may be prescribed other medicines such as exenatide or liraglutide. These medicines are given by injection and work by helping your body to make more insulin when it’s needed. They can also reduce your appetite and help you lose weight.

If lifestyle changes and medicines can’t keep your blood glucose levels under control, you may need to have insulin injections as well as, or instead of, tablets.

You will usually inject yourself with insulin once or twice a day, using either a small needle or a pen-type syringe with replaceable cartridges. There are several different types of insulin that work at different rates and for different lengths of time. Ask your GP for advice on which type is best for you.

If you have insulin injections, you will need to monitor your blood glucose levels with a home test kit. This involves taking a pinprick of blood from your finger and putting a drop on a testing strip. A meter will read the result automatically. Your GP or diabetes specialist nurse will show you how to monitor your blood glucose levels and tell you how often you need to check it.

Monitoring your blood glucose level

You may also need to have your levels of HbA1C tested at least twice a year. The test is done by taking blood from a vein in your arm or sometimes a drop of blood from a fingerprick. It’s used to see how well you’re controlling your blood sugar levels.

For answers to frequently asked questions on this topic, see FAQs.

For sources and links to further information, see Resources.