Background

Every cell in the body needs energy to function. The body's primary energy source is glucose, a simple sugar that results from the digestion of foods containing carbohydrates (sugars and starches). Glucose from digested food circulates in the blood (blood glucose) as a ready energy source for cells. Insulin is a hormone produced by cells in the pancreas and released into the bloodstream. Insulin binds to receptor sites on the outside of cells and acts like a key to open a doorway into the cell through which glucose can enter. When not enough insulin is produced or when the doorway no longer recognizes the insulin key (a condition called insulin resistance), glucose stays in the blood instead of entering the cells. This results in high blood glucose levels, a condition called hyperglycemia.

For the body to function properly, the level of glucose in the blood must remain stable within fairly narrow limits. When the blood glucose level gets too high, the body attempts to dilute the concentration of glucose in the blood by drawing water out of the cells and into the bloodstream. The excess glucose, along with water, is then excreted in urine. It is common for people with undiagnosed or uncontrolled diabetes to be constantly thirsty, to drink large quantities of water, and produce large quantities of dilute, sweet-smelling urine as their bodies try to remove excess glucose from the blood.

At the same time that the body is trying to remove glucose from the blood, the cells are starving for glucose and sending signals to the body to eat more food, thus causing people with diabetes to be constantly hungry. To provide energy for the starving cells, the body also converts fats and proteins into glucose, an activity that does not require insulin. The breakdown of fats and proteins for energy causes acid compounds called ketones to form in the blood. These ketones cause the breath of an uncontrolled diabetic to smell like acetone (nail polish remover). Ketones are also excreted in urine. As ketones build up in the blood, the blood becomes more acidic and a condition called ketoacidosis can occur. If left untreated, ketoacidosis can lead to coma and death.

Types of diabetes mellitus

Type 1 diabetes begins most often during childhood or adolescence. In this type of diabetes, the pancreas produces little or no insulin. Type 1 diabetes is characterized by a sudden onset. It occurs more frequently in people of northern European ancestry than in those from southern European countries, the Middle East, or Asia. This form of diabetes also is called insulin-dependent diabetes because people who develop type 1 diabetes need injections of insulin one or more times daily.

Brittle diabetics, sometimes called uncontrolled diabetics, are a subgroup of individuals with type 1 diabetes. These individuals, even when carefully complying with their insulin and diet regimen, have frequent and rapid swings of blood sugar levels moving between hyperglycemia (a condition in which there is too much glucose or sugar in the blood) and hypoglycemia (a condition in which there are abnormally low levels of glucose or sugar in the blood). These diabetics may require several injections of different types of insulin or an insulin pump during the day to keep their blood sugar within a fairly normal range.

The more common form of diabetes, type 2 diabetes, occurs in approximately 3 to 5% of Americans under age 50, and increases to 10 to 15% in those older than 50. More than 90% of the diabetics in the United States are type 2 diabetics. Symptoms of type 2 diabetes are milder than those of type 1 diabetes. As a result, many people (as many as 80% in some developing countries) with type 2 diabetes remain undiagnosed. This form of diabetes occurs most often in people who are overweight and who do not get adequate exercise. It also is more common in people of Native American, Hispanic, and African American descent. Type 2 diabetes appears to be somewhat linked to diet. People who have migrated to Western cultures from East India, Japan, and Australian Aboriginal cultures are more likely to develop type 2 diabetes than those who remain in their original countries.

Type 2 diabetes is initially a milder form of diabetes because of its slow onset (sometimes developing over the course of several years) and because it can often be controlled with diet, exercise, and oral medication instead of insulin injections. The consequences of uncontrolled and untreated type 2 diabetes, however, are just as serious as those for type 1. This form of diabetes also is called noninsulin-dependent diabetes, a term that is somewhat misleading. Many people with type 2 diabetes can control the condition with diet and oral medications; however, when this fails, insulin injections are necessary.

Another form of diabetes, called gestational diabetes, can develop during pregnancy. It usually resolves after the baby is delivered. This diabetic condition develops during the second or third trimester of pregnancy in about 2% of pregnancies. The condition usually is treated by diet; however, insulin injections may be required. Women who have diabetes during pregnancy are at higher risk for developing type 2 diabetes within 5 to 10 years.

Diabetes also can develop as a result of pancreatic disease, alcoholism, malnutrition, or other severe illnesses that stress the body and damage the pancreas.

Urine tests

Clinistix and Diastix are paper strips or dipsticks that change color when dipped in urine. The test strip is compared to a chart that shows the amount of glucose in the urine based on the change in color. The level of glucose in the urine lags behind the level of glucose in the blood. Testing the urine with a test stick, paper strip, or tablet is not as accurate as blood testing, however it can give a fast, simple, noninvasive reading.

Ketones in the urine can be detected using similar types of dipstick tests (Acetest or Ketostix). Ketoacidosis can be life-threatening in type 1 diabetics, so having a quick and simple test to detect ketones can assist in establishing a diagnosis rapidly.

Another dipstick test can determine the presence of protein or albumin in the urine. Protein in the urine can indicate problems with kidney function and can be used to track the development of renal failure. A more sensitive test for urine protein uses radioactively tagged chemicals to detect microalbuminuria, small amounts of protein in the urine, which may not show up on dipstick tests.

Blood tests

In a fasting plasma glucose test (FPT), blood is drawn from a vein in the patient's arm after the patient has not eaten for at least eight hours, usually in the morning before breakfast. The red blood cells are separated from the sample and the amount of glucose is measured in the remaining plasma. A plasma level of 99 mg/dL or below is normal. Readings of 100-125 mg/dL indicate pre-diabetes (impaired fasting glucose) and readings of 126 mg/dL or greater indicate diabetes. The fasting glucose test is usually repeated on another day to confirm the results. A postprandial glucose test in which blood is taken shortly after the patient has eaten a meal may also be done.

In the oral glucose tolerance test, blood samples are taken from a vein before and after a patient drinks a sweet syrup of glucose and other sugars. In a non-diabetic, the level of glucose in the blood goes up immediately after the drink and then decreases gradually as insulin is used by the body to metabolize, or absorb, the sugar. In a person with diabetes, the glucose in the blood goes up and stays high after drinking the sweetened liquid. A plasma glucose level after two hours that is 139 mg/dL is normal. Two-hour readings of 140 to 199 mg/dL indicate pre-diabetes and readings of 200 mg/dL or higher at two hours after drinking the syrup and at one other point during the two-hour test period confirms the diagnosis of diabetes.

In 2002, scientists announced that a simple blood test to screen for diabetes had been developed. Before that time, community-wide screening procedures had not proven cost-effective. The screening test was shown to be cost-effective if conducted in physician offices on patients with the three known risk factors of obesity, self-reported high blood pressure, and family history of diabetes.

Home blood glucose monitoring kits are available so diabetics can monitor their own levels. A small needle or lancet is used to prick the finger and a drop of blood is collected and analyzed by a monitoring device. Some patients may test their blood glucose levels several times during a day and use this information to adjust their diet or insulin dosage.

In the United States beginning in the early 2000s, a small number of service dogs, mostly Labrador retrievers, were trained to detect ketones in their diabetic human companions by smell. The dogs are trained to give a behavioral signal to the handler if they detect a smell that indicates the handler's metabolism is out of balance. Their acute sense of smell allows them to warn the diabetic handler of problems before the person can physically sense them. These dogs are permitted to travel in public places with their handlers under the Americans with Disabilities Act.

Diet

Both conventional and alternative medicine practitioners agree that diet and moderate exercise are the first treatments to be implemented in diabetes. For overweight and obese type 2 diabetics, weight loss is an important goal to help them to control their blood glucose levels. A well-balanced, nutritious diet provides approximately 50 to 60% of calories from carbohydrates, approximately 10 to 20% of calories from protein, and less than 30% of calories from fat. The number of calories required depends on the patient's age, weight, and activity level. Calorie intake also needs to be distributed fairly evenly over waking hours so that surges of glucose entering the blood are kept to a minimum. Generally, whole grains and foods that provide large amounts of dietary fiber are helpful in controlling blood glucose levels and reducing glucose surges in people with type 2 diabetes.

Keeping track of the number of calories provided by different foods can be complicated, so patients are usually advised to consult a nutritionist or dietitian. An individualized, easy-to-manage diet plan can be set up for each patient. Both the American Diabetes Association and the American Dietetic Association recommend diets based on the use of food exchange lists. Each food exchange contains a known amount of calories in the form of protein, fat, or carbohydrate. A patient's diet plan will consist of a certain number of exchanges from each food category (meat or protein, fruits, breads and starches, vegetables, and fats) to be eaten at meal times and as snacks. Patients have flexibility in choosing the foods they eat as long as they do not exceed the number of exchanges prescribed. The food exchange system, along with a plan of moderate exercise, can help diabetics lose excess weight and improve their overall health. Certain foods will be emphasized over others to promote a healthy heart as well.

Supplements

Supplement use to control blood glucose levels is controversial, as many studies have either produced conflicting results or have been done using such a small number of patients that their general validity can be questioned. Patients should be sure to inform their healthcare provider of all herbal and dietary supplements and over-the-counter medications that they are taking because these remedies may enhance or diminish the effects of conventional drugs used to treat diabetes.

Traditional Chinese medicine

In one study, non-insulin dependent diabetics who practiced daily qigong for one year had decreases in fasting blood glucose and blood insulin levels. Qigong also provides general health benefits.

Acupuncture may relieve pain in patients with diabetic neuropathy, a condition in which the nerves of the spinal column degenerate due to diabetes. Some studies have suggested that acupuncture also may help to bring blood glucose to normal levels in diabetics who do not require insulin.

When used in consultation with a traditional Chinese medicine practitioner, some traditional Chinese herbal medicines are believed to alleviate symptoms of or complications from diabetes. However, none of these treatments eliminates the need for insulin in people with type 1 diabetes or weight and diet control (and possibly medications) in people with type 2 diabetes. These traditional Chinese medicines include:

• Xiao Ke Wan (Emaciation and Thirst Pill) for diabetics with increased levels of sugar in blood and urine.
• Yu Quan Wan (Jade Spring Pill) for diabetics with a deficiency of Yin.
• Liu Wei Di Huang Wan (Six Ingredient Pill with Rehmannia) for stabilized diabetics with a deficiency of Kidney Yin.
• Jin Gui Shen Wan (Kidney Qi Pill) for stabilized diabetics with a deficiency of Kidney Yang.

Herbs

Herbal medicines can have a positive effect on blood glucose and quality of life in diabetics. Herbs recommended by herbal practitioners to help control blood glucose levels include the following:

• ginseng (genus Panax), shown to moderately lower blood glucose levels in several well-designed clinical trials.
• wormwood (Artemisia herba-alba ), shown to decreased blood glucose.
• gurmar (Gymnema sylvestre ), thought to decrease blood glucose levels and the need for insulin.
• Coccinia indica , believed to improved glucose tolerance.
• fenugreek seed powder (Trigonella foenum graecum ) shown to decrease blood glucose and improved glucose tolerance.
• bitter melon (Momordica charantia ) believed to decrease blood glucose and improved glucose tolerance.
• cayenne pepper (Capsicum frutescens ) to help relieve pain in the peripheral nerves (a type of diabetic neuropathy).

Other herbals that may treat or prevent diabetes and its complications include the following:

• bilberry (Vaccinium myrtillus ) may lower blood glucose levels and maintain healthy blood vessels.
• garlic (Allium sativum ) may lower blood sugar and cholesterol levels.
• onions (Allium cepa ) may help lower blood glucose levels.
• ginkgo (Ginkgo biloba ) may improve blood circulation.

Yoga

Studies of diabetics have shown that practicing yoga leads to decreases in blood glucose, increased glucose tolerance, decreased need for diabetes medications, and improved insulin processes. Yoga also enhances the sense of wellbeing and improves circulation and flexibility.

Biofeedback

Many studies have been performed to test the benefit of adding biofeedback to the diabetic's treatment plan. Relaxation techniques, such as visualization, usually were included. Biofeedback can have significant effects on diabetes, including improved glucose tolerance and decreased blood glucose levels. In addition, biofeedback can be used to treat diabetic complications and improve quality of life.

Oral medications

Oral prescription medications are available to lower blood glucose in type 2 diabetics. Drugs first prescribed for type 2 diabetes are in a class of compounds called sulfonylureas and include tolbutamide, tolazamide, acetohexamide, chlorpropamide, glyburide, glimeperide, and glipizide. The way that these drugs work is not well understood; however, they seem to stimulate cells of the pancreas to produce more insulin. Other drugs available to treat diabetes include metformin, acarbose, and troglitizone. These medications are not a substitute for a well-planned diet and moderate exercise. Oral medications are not effective for type 1 diabetes, in which the patient produces little or no insulin.

Insulin

Patients with type 1 diabetes need daily injections of insulin to help their bodies use glucose. Some patients with type 2 diabetes may need to use insulin injections if their diabetes cannot be controlled. Injections are given subcutaneously--just under the skin, using a small needle and syringe. Insulin comes in many forms, including rapid-acting, short-acting, intermediate-acting, long-acting, and pre-mixed (several types in a specific ratio) insulin. Synthetic human insulin is commonly considered superior to bovine (cow) or porcine (pig) insulin. The type of insulin used varies with the age, health, and lifestyle of each diabetic. Different types of insulin can be mixed and given in one dose or split into two or more doses during a day. Patients who require multiple injections over the course of a day may be able to use an insulin pump that administers small doses of insulin on demand.

New drugs and new drug delivery systems to treat diabetes were active areas of research as of 2008. For example, in 2004, the United States Food and Drug Administration (FDA) approved a rapid-acting form of synthetic insulin, insulin glulisine (Apidra), to control hyperglycemia following meals. In 2007, the FDA approved a new delivery system for insulin glargine (Lantus) called LantusSoloStar, which consists of individual pre-loaded insulin pens to be used once daily at bedtime. Because the number of individuals with diabetes was expected to rise substantially between 2008 and 2018, research on new drugs, delivery systems, and blood glucose test kits was likely to remain vigorous.

Hypoglycemia, or low blood sugar, is a condition that can be caused by too much insulin, eating too little food, eating too late to coincide with the action of the insulin, alcohol consumption, or increased exercise. A patient with symptoms of hypoglycemia may be hungry, sweaty, shaky, cranky, confused, and tired. Left untreated, the individual can lose consciousness or have a seizure. This condition is sometimes called an insulin reaction or "insulin shock" and should be treated by giving the individual something sweet to eat or drink such as candy, sugar cubes, or juice.

Surgery

Transplantation of a healthy pancreas into a person with type 1 diabetes might seem like a successful treatment. Nevertheless, this transplant usually is done only if a kidney transplant is performed at the same time. Transplanted pancreases are rejected about half the time, so in many cases the potential benefits of transplantation are overshadowed by the risks of the surgery and subsequent immune system drug therapy.

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