The full name of diabetes is "Diabetes mellitus". "Diabetes" comes from the ancient Greek for excessive urination, and Mellitus comes from the Latin for honey, referring to the sugar that appears in the urine of people with diabetes. This fact was used in diagnosis by doctors until chemical tests for sugar in urine became readily available – tasting the urine was the way to diagnose the condition!
The underlying problem in diabetes is the pancreas failing to make enough insulin to control levels of sugar in the blood. Insulin is released into the bloodstream in response to rising blood sugar levels after a meal, and programmes all the cells of the body to take up glucose from the bloodstream. This controls the blood sugar level. If there is not enough insulin around, then the blood sugar level rises too high.
There are two major types of diabetes, Type 1 and Type 2. A temporary form can appear in pregnancy (“Gestational diabetes”) and the word diabetes appears in the name of a completely unconnected condition, diabetes insipidus. In common with diabetes mellitus, excess urine is made, but there the link ends.Type 1: insulin-dependent diabetes. The pancreas makes virtually no insulin at all, and successful treatment depends on replacing the insulin itself. This is most common in children and young adults.
Type 2: non-insulin-dependent diabetes. The pancreas is still able to make some insulin, and treatment does not rely on insulin replacement.
Symptoms and signs of diabetes include:
- tiredness and general weakness
- excessive and constant thirst
- frequent urination
- increased appetite but weight loss
- blurred vision
- frequent infections of different sorts, but especially urinary infections, vaginal and oral thrush and fungal skin infections
- both types of diabetes tend to run in families
- the risk of non-insulin-dependent diabetes tends to rise with obesity in adults, pregnancy (gestational diabetes, which settles after giving birth) and certain drugs, especially diuretics (from the thiazide family) and long-term oral steroid treatment
Long term complications:
Untreated and uncontrolled diabetes has a serious effect on many organ systems. The raised blood sugar levels affect the small blood vessels of the heart, eyes, kidneys and feet, forming the basis for these major complications:
- arterial disease leading to stroke, coronary artery disease (angina and heart attacks) and general hardening of the arteries
- disease of the small blood vessels of the limbs, which can lead to claudication (leg pains on walking, caused by reduced blood flow through narrowed blood vessels and therefore oxygen shortage to the legs) and eventually to gangrene and loss of a limb
- kidney failure
- damage to nerves in the limbs which can cause permanent numbness (neuropathy) which makes it hard to be aware of an injury. With the already reduced blood supply and increased risk of infection, this is a risky combination
- damage to nerves in the autonomic nervous system: this part of the nervous system look after all the unconscious body control systems, such as blood pressure control reflexes. Damage from diabetes can lead to fainting on standing up (postural hypotension) and erection difficulties in men
Short term complications:If uncontrolled diabetes leads to very high blood sugar levels, a very dangerous state called diabetic ketoacidosis can develop. Excessive urine formation leads to dehydration, and the blood then becomes slightly acidic. Chemicals called ketones appear in the blood, giving a characteristic smell of pear drops to the breath. Confusion, vomiting and coma follow unless hospital treatment is started urgently.
Treatment of DiabetesTo start with, Type 2 diabetes can be treated just with dietary control of sugar intake. This concentrates on regulating the amount and frequency of intake of carbohydrates, and to reduce weight (body fat) so that whatever insulin is produced can work more efficiently. Excess body fat reduces the body’s sensitivity to insulin.
As the pancreas becomes less efficient, diet-based control stops working, and oral medication can be prescribed. There are several different kinds, which work by stimulating the pancreas to make more insulin.
Type 1 diabetes is treated with insulin, derived from pork or beef, or genetically engineered synthetic human insulin. At the moment, this is only given by injection. An inhaled version has been developed but has been problematic and is not currently in use. The possibility of insulin in tablet form is not far away.
Other treatments such as statins to reduce cardiovascular risk, and “ACE Inhibitors” (drugs to lower blood pressure that also help protect the kidneys in diabetes) are usually offered, and preventative check-ups for the eyes (retinal photography) and feet (seeing a podiatrist) as well as regular GP diabetes clinic check ups are essential – drug treatment is only one part of managing diabetes. Good self care is made much easier by making full use of GP services for diabetes.
The futureWe are living in interesting times. Leonard Thompson of Canada was the first patient to receive injections of cattle pancreatic extract on January 11, 1922. Up till then the only treatment was a diet high in fat and protein, allowing people with Type I diabetes to live for about a year after diagnosis. The first synthetic human insulin was made on September 6th 1978 in San Francisco. In early 2005, Richard Lane of Bromley, Kent, became the first person in the UK to be cured of Type I diabetes after receiving a pancreatic islet cell transplant at King’s College Hospital, London.
What next? Perhaps gene therapy to cure the condition completely, and allow normal pancreas cells to regrow.
This rate of progress spells hope for all currently living with diabetes –a cure is no longer in the realms of science fiction.
Carers: practical support
NHS Guide: diabetes
Live Well: diabetes facts
Health A-Z: diabetic retinopathy
Health A-Z: type 1 diabetes
Diabetes / Easy health
National Obesity Forum