What is it?
Diabetes mellitus is a medical condition characterised by excessive glucose in the blood (hyperglycaemia) due to the absolute or relative deficiency of a substance called insulin. Absolute deficiency means that the body does not produce insulin at all (also called Type 1 diabetes). Relative deficiency means that the body is either not making enough insulin or is not able to utilise it (Type 2 diabetes).
Glucose comes from food and supplies the body with energy. Insulin helps keep the levels of glucose steady and within safe limits. But in diabetes, glucose builds up in the blood and causes a whole lot of problems.
Type 1 diabetes is less common (about 10 percent) and usually occurs in people less than 40. Type 2 diabetes starts gradually, usually when you’re 40 or over. It is much more common and that’s what will be discussed here.
Who gets diabetes?
Diabetes affects more than 220 million people worldwide, and it is estimated that this number will double by the year 2030. Type 2 diabetes is a common condition in all populations enjoying an affluent lifestyle, and has increased in parallel with the adoption of a western lifestyle and increasing obesity.
The four major determinants are:
- Increasing age
- Family history
In poor countries, diabetes is a disease of the rich, but in rich countries, it is a disease of the poor; obesity being the common factor.
Type 2 diabetes is commoner in people of South Asian, African and Caribbean ancestry, but the reason for this is unclear.
For women, having had a type of diabetes while pregnant (called gestational diabetes) increases the chance of getting diabetes later in life.
Problems with the heart or blood vessels (cardiovascular disease) or having excess “bad fat” in the blood also predisposes to diabetes.
How do I know I have diabetes?
Diabetes can present in either of three ways:
Acute presentation: Young people often report the three classic symptoms of excessive urination, excessive thirst and weight loss occurring for about 2-6 weeks.
Subacute presentation: In older people, the symptoms take a longer time (months or years) to show up. Excessive urination, thirst and weight loss are typically present but there could also be complaints of visual blurring, lack of energy and genital itch.
Asymptomatic diabetes: Glucose in urine or a raised blood glucose may be detected on routine examination (such as for insurance purposes) in individuals who have no symptoms of diabetes. Further confirmatory tests are needed in this case.
There are some symptoms you need to watch out for, because they mean your blood glucose may have got very high. These include feeling light-headed, dizzy, sick, or confused, or losing consciousness. If you get these symptoms you need immediate medical help.
How do doctors diagnose diabetes?
If the doctor suspects you have diabetes, they will carry out a blood test to find out how much glucose is in your blood. The most usual test for diabe
tes measures glucose levels first thing in the morning, before breakfast. The result is called the fasting plasma glucose level. If it is more than 7mmol/L, it suggests diabetes. If the blood glucose level is checked after food, the result is called a random plasma glucose level. If it is more than 11.1 mmol/L. it also suggests diabetes. A second test is needed to confirm either test.
A costlier but more accurate test is a type of blood test called an HbA1c test. It gives an idea of what the average blood glucose has been for the past 3 months.
The doctor may also want to run some more blood and urine tests to find out how well other organs that may be affected by diabetes are working. They will schedule regular periodic appointments to monitor the disease progression and treatment. The frequency of these other visits will depend largely on their findings after assessment.
Treatments for diabetes
Having type 2 diabetes increases the risks of having two main categories of health problems:
• problems with the larger blood vessels, leading to heart attacks and strokes (called macrovascular complications)
• problems with the smaller blood vessels in the eyes, kidneys, and feet (called microvascular complications).
Proper and timely treatments are needed to prevent these complications or to control them when they have started occurring already. These include drugs to control blood sugar, blood pressure and cholesterol.
Regular exercise helps to control weight and reduce the risk of heart problems. Blood pressure control is vital using appropriate antihypertensive drugs which the doctor prescribes. Most patients will also benefit from statins for cholesterol control and low-dose aspirin for risk of clotting.
The role of the diabetic:
The care of diabetes is based on self-management, and the outcome of treatment depends on willing cooperation by the diabetic. This in turn depends on an understanding of the risks of diabetes and the potential benefits of controlling blood sugar and other measures such as maintaining a lean weight, stopping smoking and taking care of the feet. The doctor will properly educate you soon after diagnosis.
There is no “special” food for people with diabetes. Their diet is no different from that considered healthy for everyone. In essence, their food should be:
- Low in sugar (though not sugar-free)
- High in starchy carbohydrate, for slower absorption
- High in fibre
- Low in fat (especially saturated fat)
The dietician should give a better guidance and advice on how to go about with the dieting, so the doctor invites them to do that.
Diet treatment is incomplete without exercise. Exercise should be done by everyone with diabetes. Several studies have shown a slower progression and reduced long-term mortality in diabetics who have very high levels of fitness. The overweight or obese are especially encouraged to lose weight by a combination of changes in food intake and physical activity.
Tablets to control blood sugar:
It is important to always remember that diet and lifestyle changes are the key to successful treatment of type 2 diabetes, and no amount of medication will succeed where these have failed. Controlling diabetes is not just about swallowing tablets, and the doctor usually never prescribes any drugs until the other issues have been addressed. These tablets are only needed if satisfactory results are not seen within 4-6 weeks.
There are several types of medicine that can help keep your blood sugar levels under
control. But the three main options are:
- Metformin (common brand name is Glucophage); which helps the body respond better to insulin.
- Sulphonylureas; which increase the production of insulin by the pancreas.
- Glitazones; which reduce the resistance of the body to insulin.
Metformin remains the single best drug for type 2 diabetes. However, not everyone needs the same level of treatment, and different medicines suit some people better than others. So your doctor should determine what is best for you, and explain the possible effects of the treatment he has chosen. Remember to discuss your concerns with them and ask any questions you may have.
Injections to control blood sugar
In type 2 diabetes, insulin production progressively decreases over time. This implies that most people on tablets alone will eventually require insulin. If glucose control is inadequate on oral drugs, insulin should be started as soon as possible.
Insulin is used as an injection, usually into the fat below the skin on the thighs, abdomen or upper arm. The needles used are very fine and sharp so the injections are virtually painless. Insulin is usually administered by a pen injection device, and your doctor will teach you how to use it on yourself. The injection site should be changed regularly to prevent fatty lumps from forming. Absorption is more rapid from the abdomen than from the arm, and is slowest from the thigh.
What will happen to me?
People with diabetes should be able to lead a normal life with good glucose control using appropriate medicines, diet and exercise. Apart from these changes, you should be able to take part in all your normal activities.
There are complications which may arise from poor management, and these should be looked out for. They include problems with your eyes, kidneys, and feet. These could be avoided by adhering to treatment and having regular health checks.
Learn more about diabetes from the self-help books below: