Diabetes Mellitus.
Publié le 11/05/2013
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Once diabetes is diagnosed, treatment consists of controlling the amount of glucose in the blood and preventing complications.
Depending on the type of diabetes, thiscan be accomplished through regular physical exercise, a carefully controlled diet, and medication.
Individuals with Type 1 diabetes must receive insulin, often two to four times a day, to provide the body with the hormone it does not produce.
Insulin cannot be takenorally, because it is destroyed in the digestive system.
Consequently, insulin-dependent diabetics have historically injected the drug using a hypodermic needle or abeeper-sized pump connected to a needle inserted under the skin.
In 2006 the United States Food and Drug Administration approved a form of insulin that can beinhaled and then is absorbed by blood in the lungs.
The amount of insulin needed varies from person to person and may be influenced by factors such as a person’s level of physical activity, diet, and the presence ofother health disorders.
Typically, individuals with Type 1 diabetes use a meter several times a day to measure the level of glucose in a drop of their blood obtained bypricking a fingertip.
They can then adjust the dosage of insulin, physical exercise, or food intake to maintain the blood sugar at a normal level.
People with Type 1diabetes must carefully control their diets by distributing meals and snacks throughout the day so as not to overwhelm the ability of the insulin supply to help cellsabsorb glucose.
They also need to eat foods that contain complex sugars, which break down slowly and cause a slower rise in blood sugar levels.
Although most persons with Type 1 diabetes strive to lower the amount of glucose in their blood, levels that are too low can also cause health problems.
For example, ifa person with Type 1 diabetes takes too much insulin, it can produce low blood sugar levels.
This may result in hypoglycemia , a condition characterized by shakiness, confusion, and anxiety.
A person who develops hypoglycemia can combat symptoms by ingesting glucose tablets or by consuming foods with high sugar content, suchas fruit juices or hard candy.
In order to control insulin levels, people with Type 1 diabetes must monitor their glucose levels several times a day.
In 1983 a group of 1,441 Type 1 diabetics aged 13to 39 began participating in the Diabetes Control and Complications Trial (DCCT), the largest scientific study of diabetes treatment ever undertaken.
The DCCT studiedthe potential for reducing diabetes-related complications, such as nerve or kidney disease or eye disorders, by having patients closely monitor their blood sugar levelsfour to six times a day, maintaining the levels as close to normal as possible.
The results of the study, reported in 1993, showed a 50 to 75 percent reduction of diabeticcomplications in people who aggressively monitored and controlled their glucose levels.
Although the study was performed on people with Type 1 diabetes, researchersbelieve that close monitoring of blood sugar levels would also benefit people with Type 2 diabetes.
For persons with Type 2 diabetes, treatment begins with diet control, exercise, and weight reduction, although over time this treatment may not be adequate.
Peoplewith Type 2 diabetes typically work with nutritionists to formulate a diet plan that regulates blood sugar levels so that they do not rise too swiftly after a meal.
Arecommended meal is usually low in fat (30 percent or less of total calories), provides moderate protein (10 to 20 percent of total calories), and contains a variety ofcarbohydrates, such as beans, vegetables, and grains.
Regular exercise helps body cells absorb glucose—even ten minutes of exercise a day can be effective.
Dietcontrol and exercise may also play a role in weight reduction, which appears to partially reverse the body’s inability to use insulin.
For some people with Type 2 diabetes, diet, exercise, and weight reduction alone may work initially, but eventually this regimen does not help control high blood sugarlevels.
In these cases, oral medication may be prescribed.
If oral medications are ineffective, a person with Type 2 diabetes may need insulin doses or a combination oforal medication and insulin.
About 50 percent of individuals with Type 2 diabetes require oral medications, 40 percent require insulin or a combination of insulin and oralmedications, and 10 percent use diet and exercise alone.
VI CURRENT RESEARCH
At present no cure exists for diabetes, and scientists are unsure of the exact cause, although researchers are investigating a combination of genetic and environmentalfactors.
So far researchers have identified 20 genes involved in Type 1 diabetes, and they are working to determine each gene’s role in causing the disease.
Theinheritance patterns of Type 1 diabetes are complicated, with many different genes influencing a person’s risk.
For instance, a gene known as DR plays a role in Type 1diabetes.
Two forms of this gene, called DR3 and DR4, are present in 95 percent of people with Type 1 diabetes.
People who inherit DR3 alone develop diabetes at anolder age and have antibodies that destroy insulin-producing beta cells.
Those who inherit DR4 tend to develop diabetes earlier in life and have antibodies that destroyinsulin.
A person with both DR3 and DR4 typically develops diabetes at a very young age and has the highest level of insulin-destroying antibodies.
In 2000 researchers were surprised to find that a variation of a gene called Caplain-10, which is not involved in glucose metabolism, is associated with the developmentof Type 2 diabetes.
One form of this gene produces a small amount of protein, and researchers are studying how this decrease in protein increases a person’s risk fordiabetes.
Other genetic studies indicate that certain genes cause a variation of Type 2 diabetes called maturity onset diabetes of the young (MODY), which develops inpeople under the age of 25.
Although scientists do not yet understand how these genes cause MODY, the genes are known to be active in the liver, intestine, kidney,and pancreas.
Other scientists hope to identify the environmental factors that trigger Type 1 diabetes in people with a genetic predisposition for the disease.
If they can determinewhat causes the immune system to attack the cells that produce insulin, they may discover how to prevent the condition from developing.
For instance, studies suggestthat certain viruses, such as coxsackie B, rubella, and mumps, may trigger an immune reaction against beta cells or in some cases directly infect and destroy thesecells.
Researchers attribute most cases of Type 2 diabetes to obesity.
Studies show that the risk for developing Type 2 diabetes increases by 4 percent for every pound ofexcess weight a person carries.
Researchers are investigating the exact role that extra weight plays in preventing the proper utilization of insulin and why someoverweight people develop the disease while others do not.
Research also focuses on transplanting a healthy pancreas or its insulin-producing beta cells into a person with Type 1 diabetes to provide a natural source of insulin.Some patients who have received pancreas transplants have experienced considerable improvements in their health, but positive, long-term results with beta-celltransplants have not yet occurred.
In both types of transplants recipients must take drugs that suppress their immune systems so the body will not reject the newpancreas or cells.
These drugs can cause life-threatening side effects because the patient’s body can no longer protect itself from other harmful substances.
In mostpeople with diabetes, these drugs pose a greater risk to health than living with diabetes.
Scientists are also studying the development of an artificial pancreas and waysto genetically manipulate non-insulin-producing cells into making insulin.
New methods for accurately measuring blood glucose levels may improve the quality of life for many individuals with diabetes.
New techniques include the use of laserbeams and infrared technology.
For example, a tiny computer using infrared light can be used to measure a person’s blood sugar level.
The computer automaticallydelivers the reading to an insulin pump carried on the diabetic’s body that injects the appropriate amount of insulin.
Other advances include new drugs that control blood sugar.
In April 2000 the United States Food and Drug Administration (FDA) approved glargine, an insulin drug thatneeds to be injected only once a day.
Sold under the brand name Lantus, this drug can be used by people with Type 1 diabetes, as well as by those with Type 2diabetes who require insulin injections.
And, as mentioned earlier, in 2006 the FDA approved a form of insulin that can be inhaled.
Physicians have long known thatsome insulin-dependent diabetics fail to take the drug as often as needed because of the discomfort of injections.
Doctors hoped the inhalant form of insulin would leadto better patient compliance..
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