- Diabetes, also known as diabetes mellitus, is a chronic health condition where the body is unable to produce enough insulin and properly break down sugar (glucose) in the blood. Glucose comes from food and is used by the cells for energy. Glucose is also made in the liver. Insulin is a hormone produced by the pancreas, a large gland behind the stomach. Insulin is needed to move sugar into the cells where it can be used for energy needed for body processes.
- After digestion of food, glucose passes into the bloodstream. For glucose to get into cells, insulin must be present. Throughout the pancreas are clusters of cells called the islets of Langerhans. Islets are made up of several types of cells, including beta cells that make insulin. When normal individuals eat, beta cells in the pancreas automatically produce the right amount of insulin to move glucose from blood into the cells of the body. In individuals with diabetes, however, the pancreas either produces little or no insulin, or the cells do not respond appropriately to the insulin that is produced. Glucose builds up in the blood, overflows into the urine, and passes out of the body in the urine. Thus, the body loses its main source of fuel even though the blood contains large amounts of glucose. Glucose may also interact with cells, especially those in very narrow blood vessels. This process may lead to neuropathies and decreased immune function.
- With Type 1 diabetes, the body does not make any insulin. With Type 2 diabetes, the more common type, the body does not make or use insulin properly. Without enough insulin, glucose stays in the blood and causes a condition called hyperglycemia, or high blood sugar levels.
- Diabetes is associated with long-term complications that affect almost every part of the body. The disease often leads to blindness, heart and blood vessel disease, stroke, kidney failure, amputations, and nerve damage. Uncontrolled diabetes can complicate pregnancy, and birth defects are more common in babies born to women with diabetes. Pregnant women can temporarily develop gestational diabetes, a type of diabetes that begins late in pregnancy.
- In 2007, an estimated 20.8 million children and adults in the United States, or 7% of the population, had diabetes mellitus. An estimated 14.6 million have been diagnosed with diabetes (both type 1 and type 2), while 6.2 million people (or nearly one-third) are unaware that they have type 2 diabetes.
- Diabetes is widely recognized as one of the leading causes of death and disability in the United States. The U.S. Centers for Disease Control (CDC) recognizes diabetes as the 6th leading cause of death in the United States, with over 72,000 deaths in 2004.
Signs and symptoms
- Type 1 diabetes:
- Symptoms of type 1 diabetes are often dramatic and come on very suddenly. Type 1 diabetes is usually recognized in childhood or early adolescence, often in association with an illness (such as a virus) or injury. The initial symptoms of type 1 diabetes are: an increased production of urine, excessive thirst, fatigue, tiredness, loss of weight, increased appetite, feeling sick, blurred vision, and infections such as thrush or irritation of the genitals.
- Type 1 diabetics can develop diabetic ketoacidosis. Ketoacidosis is a serious condition where the body has dangerously high levels of ketones. Ketones are substances that are made when the body breaks down fat for energy. Normally, the body gets the energy it needs from carbohydrates. However, stored fat is broken down and ketones are made if the diet does not contain enough carbohydrates to supply the body with sugar (glucose) for energy, or if the body cannot use blood sugar (glucose) properly, as in diabetes. Symptoms of ketoacidosis include nausea and vomiting. Dehydration and often-serious disturbances in blood levels of potassium follow. Without treatment, ketoacidosis can lead to coma and death.
- Type 2 diabetes:
- Symptoms of type 2 diabetes are often subtle and may be attributed to aging or obesity. An individual may have type 2 diabetes for many years without knowing it. Individuals with type 2 diabetes can develop hyperglycemic hyperosmolar non-ketotic syndrome, which is characterized by no or few ketones and high glucose in the blood
- Some individuals who have type 2 diabetes have patches of dark, velvety skin in the folds and creases of their bodies, usually in the armpits and neck. This condition, called acanthosis nigricans, is a sign of insulin resistance.
- If not properly treated, type 2 diabetes can lead to complications such as blindness, kidney failure, heart disease, and nerve damage.
- Maturity-onset diabetes of the young (MODY):
- Maturity-onset diabetes of the young (MODY) may occur during childhood or adolescence, but may be misdiagnosed as Type 1 or Type 2 diabetes, or may be unidentified until the patient is an adult. Individuals with MODY may have little to no symptoms of diabetes, or have only mild symptoms, or may have mild to significant hyperglycemia. MODY patients are typically not overweight, and generally do not have similar risk factors as seen with Type 2 diabetes, such as hypertension (high blood pressure), or hyperlipidemia (elevated serum lipids).
- Many patients with MODY do not have any symptoms of diabetes, and may be diagnosed with high serum glucose while in the process of discovering other disorders. Other symptoms may include increased thirst and urination. It is recommended that if an individual has mild to moderate hyperglycemia identified before the age of 30, a family history of diabetes, and low insulin requirements, that they be tested for MODY.
- Common symptoms of Type 1 and Type 2 diabetes:
- Fatigue: In diabetes, the body is inefficient and sometimes unable to use glucose for fuel. The body switches over to metabolizing fat, partially or completely, as a fuel source. This process requires the body to use more energy. The end result is feeling fatigued or constantly tired.
- Unexplained weight loss: Individuals with diabetes are unable to process many of the calories in the foods they eat. Therefore, they may lose weight even though they eat an apparently appropriate or even excessive amount of food. Losing sugar and water in the urine and the accompanying dehydration also contributes to weight loss.
- Excessive thirst (polydipsia): An individual with diabetes develops high blood sugar levels. The body tries to counteract this by sending a signal to the brain to dilute the blood, which translates into thirst. The body encourages more water consumption to dilute the high blood sugar back to normal levels and to compensate for the water lost by excessive urination.
- Excessive urination (polyuria): Polyuria is frequent urination. Another way the body tries to get rid of the extra sugar in the blood is to excrete it in the urine. This can also lead to dehydration because excreting the sugar carries a large amount of water out of the body along with it.
- Excessive eating (polyphagia): Polyphagia is excessive hunger. If the body is able, it will secrete more insulin in order to try to deal with the excessive blood sugar levels. One of the functions of insulin is to stimulate hunger. Therefore, higher insulin levels lead to increased hunger and eating. Despite increased caloric intake, the person may gain very little weight or may even lose weight.
- Poor wound healing: White blood cells are important in defending the body against bacteria and also in cleaning up dead tissue and cells. High blood sugar levels prevent white blood cells from functioning normally. When these cells do not function properly, wounds take much longer to heal and become infected more frequently.
- Vascular problems: Long-term high blood sugar levels are associated with thickening of blood vessels, which prevents good circulation and body tissues from getting enough oxygen and other nutrients.
- Infections: Certain infection syndromes, such as frequent yeast infections, skin infections, and frequent urinary tract infections, may result from suppression of the immune system by diabetes and by the presence of glucose in the tissues, which allow bacteria to grow well. They can also be an indicator of poor blood sugar control in a person known to have diabetes.
- Altered mental status: Agitation, unexplained irritability, inattention, extreme lethargy, or confusion can all be signs of very high blood sugar, ketoacidosis, hyperosmolar hyperglycemia nonketotic syndrome, or hypoglycemia (low sugar). These merit the immediate attention of a medical professional. Call a healthcare provider or 911.
- Blurry vision: The primary cause of legal blindness in the working population of the United States today is diabetes mellitus. Blurry vision is not specific for diabetes but is frequently present with high blood sugar levels.
- The main diagnostic test for diabetes is taking a blood test to measure glucose, either when the individual has been fasting (not consuming food) or at other times of the day. Diagnostic tests are also used routinely during pregnancy to identify gestational diabetes. Some diabetes tests require obtaining a blood sample in a doctor's office.
- Depending on the test used, the level of blood glucose can be affected by many factors including: eating or drinking (water is acceptable); taking medications that are known to raise blood sugar levels, such as oral contraceptives, some diuretics (water pills) and corticosteroids; or a recent injury, physical illness, or surgery that may temporarily alter blood sugar levels.
- Fasting blood glucose test: Fasting blood glucose testing checks blood glucose levels after fasting for between 12-14 hours. The individual can drink water during this time, but should strictly avoid any other beverage. Individuals with diabetes may be asked to delay their diabetes medication or insulin dose until the test is completed. This test can be used to diagnose diabetes or pre-diabetes. The fasting plasma glucose (FPG) is the preferred test for diagnosing diabetes due to convenience and is most reliable when done on an empty stomach in the morning, so the presence of food and natural biorhythms do not cause fluctuations in blood sugar levels.
- If the fasting glucose level is 100-125 milligrams/deciliter, the individual has a form of pre-diabetes called impaired fasting glucose (IFG), meaning that the individual is more likely to develop type 2 diabetes but does not have the condition yet. A level of 126 milligrams/deciliter or above, confirmed by repeating the test on another day, means that the individual has diabetes.
- Oral glucose tolerance test: During an oral glucose tolerance test (OGTT), a high-glucose drink is given to the individual. Blood samples are checked at regular intervals for two hours. Glucose tolerance tests are used when the results of the fasting blood glucose are borderline. They are also used to diagnose diabetes in pregnancy (gestational diabetes). This test can be used to diagnose diabetes or pre-diabetes.
- Random blood glucose test: Random blood glucose testing checks blood glucose levels at various times during the day. It does not matter when the individual last ate. Blood glucose levels tend to stay constant in an individual who does not have diabetes. This test, along with an assessment of symptoms, is used to diagnose diabetes.
- Fructosamine testing: Doctors may measure the level of fructosamines, also known as glycated proteins, in serum or plasma to estimate average glucose levels in diabetic patients during the preceding two to three weeks. In diabetic patients, elevated blood glucose levels correlate with increased fructosamine formation. Fructosamine is formed due to a reaction between fructose and amino acid residues of proteins.
- Fructosamine testing is often prescribed when changes are being made in a diabetes treatment plan and information is needed about how well the new plan is working. High levels of vitamin C (ascorbic acid), lipemia (high amount of fat in the blood), hemolysis (breakdown of RBCs), and hyperthyroidism (high levels of thyroid hormones) can interfere with test results.
- Hemoglobin A1c (A1c): Hemoglobin A1c, also known as glycated hemoglobin or glycosylated hemoglobin, indicates an individual's average blood sugar control over the last two to three months. Sugar (glucose) in the bloodstream can become attached to the hemoglobin (the part of the cell that carries oxygen) in red blood cells. This process is called glycosylation. Once the sugar is attached, it stays there for the life of the red blood cell, which is about 120 days. The higher the level of blood sugar, the more sugar attaches to red blood cells. The hemoglobin A1c test measures the amount of sugar sticking to the hemoglobin in the red blood cells. A1c is formed when glucose in the blood binds irreversibly to hemoglobin to form a stable glycated hemoglobin complex. A1C values are not subject to the fluctuations that are seen with daily blood glucose monitoring. Results are given in percentages.
- The American Diabetes Association (ADA) recommends A1c as the best test to find out if an individual's blood sugar is under control over time. The test should be performed every three months for insulin-treated patients, during treatment changes, or when blood glucose is elevated. For stable patients on oral agents, healthcare professionals recommended testing A1c at least twice per year. The ADA currently recommends an A1c goal of less than 7.0%. Studies have reported that there is a 10% decrease in relative risk of microvascular complications, such as diabetic nephropathy or diabetic neuropathy, for every 1% reduction in hemoglobin A1c.
- Gestational diabetes diagnosis: Gestational diabetes is diagnosed based on blood glucose levels measured during the oral glucose tolerance test (OGTT). Glucose levels are normally lower during pregnancy, so the cutoff levels for diagnosis of diabetes in pregnancy are lower. Blood glucose levels are measured before a woman drinks a beverage containing glucose. Then levels are checked one, two, and three hours afterward. If a woman has two blood glucose levels meeting or exceeding any of the following numbers, she has gestational diabetes: a fasting blood glucose level of 95 milligrams/deciliter, a one-hour level of 180 milligrams/deciliter, a two-hour level of 155 milligrams/deciliter, or a three-hour level of 140 milligrams/deciliter.
- Maturity-onset diabetes of the young (MODY) diagnosis: Genetic testing can help diagnose MODY, however, commercially available genetic tests for MODY are not widely available. In a MODY test a blood sample is collected, and the DNA is isolated and analyzed for mutations characteristic of MODY. Genetic testing may be helpful in selecting specific treatments for MODY, depending on the specific genetic mutation involved. Prenatal testing may also be available for diagnosis of MODY. As each type of MODY has different clinical manifestations, it is recommended for the patient to work with their healthcare provider to discuss testing options, to determine whether genetic testing is appropriate, and to decide which genetic tests are necessary.
- Diabetes mellitus (diabetes) can affect many major organs in the body, including the heart, blood vessels, nerves, eyes, and kidneys. Keeping blood sugar levels close to normal most of the time can dramatically reduce the risk of these complications.
- Short-term complications:
- Short-term complications of diabetes, such as a high blood sugar level, require immediate care. Left untreated, these conditions can cause seizures and loss of consciousness (coma).
- Hyperglycemia: Hyperglycemia is a condition of high blood sugar levels. Blood sugar levels can rise for many reasons, including eating too much, stress, or not taking enough insulin or medications. It is important to check blood sugar levels often and watch for signs and symptoms of high blood sugar, including frequent urination, increased thirst, dry mouth, blurred vision, fatigue, and nausea. If hyperglycemia is present, adjustment to meal plans, medications, or both may be necessary. If blood sugar levels are persistently above 250 mg/dL, consulting a doctor immediately is recommended by healthcare providers. Diabetic hyperosmolar syndrome, a life-threatening condition in which sky-high blood sugar causes blood to become thick and syrupy, may be present.
- Diabetic ketoacidosis: Diabetic ketoacidosis is characterized by high levels of ketones in the blood. If the cells are starved for energy, the body may begin to break down fat. This produces toxic substances known as ketones. It is important to watch for loss of appetite, nausea, vomiting, fever, stomach pain, and a sweet, fruity smell on the breath, especially if the blood sugar level has been consistently higher than 250 milligrams/deciliter. Diabetic ketoacidosis is more common in type 1 diabetes than type 2.
- Hypoglycemia: Hypoglycemia is a condition of low blood sugar. If blood sugar levels drop below the target range, it is known as low blood sugar. Blood sugar levels can drop for reasons including skipping a meal, getting more physical activity than normal, or taking too much diabetic medication. It is important to check blood sugar levels regularly and to watch for early signs and symptoms of low blood sugar, including sweating, shakiness, weakness, hunger, dizziness, and nausea. Later signs and symptoms include slurred speech, drowsiness, and confusion. If signs or symptoms of low blood sugar are present, it is recommended by healthcare providers to eat or drink something that will quickly raise blood sugar levels, such as fruit juice, glucose tablets, hard candy, or regular (not diet) soda. If consciousness is lost, a family member or close contact may need to give an emergency injection of glucagon, a hormone that stimulates the release of sugar into the blood. Glucagon is a medication that is prescribed to some individuals with blood sugar regulation problems.
- Long-term complications:
- Long-term complications of diabetes develop gradually. The earlier the individual develops diabetes and the less controlled the blood sugar levels are, the higher the risk of complications. Eventually, diabetes complications may be disabling or even life-threatening.
- Heart and blood vessel disease: Diabetes dramatically increases the risk of various cardiovascular problems, including coronary artery disease with chest pain (angina), heart attack, stroke, narrowing of the arteries (atherosclerosis), and high blood pressure. According to the American Heart Association, approximately 75% of individuals who have diabetes die of some type of heart or blood vessel disease. Diabetic microangiopathy is the damage to very small blood vessels due to high blood sugar levels. Microangiopathy causes the walls of very small blood vessels (capillaries) to become so thick and weak that they bleed, leak protein, and slow the flow of blood. Diabetics may develop microangiopathy with thickening of capillaries in many areas including the eyes, feet, legs, and kidneys.
- Diabetic neuropathy: Diabetic neuropathy, or nerve damage, occurs due to excess blood sugar levels that can injure the walls of the tiny blood vessels (capillaries) that nourish the nerves, especially in the legs. Diabetic neuropathy can cause tingling, numbness, burning, or pain that usually begins at the tips of the toes or fingers and over a period of months or years gradually spreads upward. Left untreated, the individual can lose all sense of feeling in the affected limbs. Diabetic neuropathy is a common cause of limb amputations. The injuries to the skin occur and are not felt, due to neuropathy, until infection progresses too far to save the tissue, especially the toes and feet. Damage to the nerves that control digestion can cause problems with nausea, vomiting, diarrhea, or constipation. For men, erectile dysfunction may also occur as a result of poor blood flow to the penis and nerve damage, both caused by diabetes.
- Diabetic nephropathy: Diabetic nephropathy is kidney damage caused by uncontrolled high blood sugar. High blood sugar damages the filtering system of the kidneys. Over time, the damage can lead to kidney failure. Diabetic nephropathy is the most common cause of kidney failure in the United States. Severe damage can lead to kidney failure or irreversible end-stage kidney disease, requiring dialysis or a kidney transplant.
- Eye damage: Chronic high blood sugar levels damage sensitive blood vessels in the eye, resulting in blurry vision and vision damage. Diabetes can damage the blood vessels of the retina (diabetic retinopathy), potentially leading to blindness. The primary cause of legal blindness in the working population of the United States today is diabetes mellitus. Diabetes also increases the risk of other serious vision conditions, such as cataracts and glaucoma.
- Foot ulcers: Nerve damage in the feet or poor blood flow to the feet increases the risk of various foot complications, including diabetic foot ulcers. Left untreated, cuts and blisters can become serious infections. Severe damage might require toe, foot, or even leg amputation.
- Skin and mouth conditions: Diabetes may leave the individual more susceptible to skin problems, including bacterial infections, fungal infections, and itching. Gum infections also may be a concern, especially if there is a history of poor dental hygiene.
- Osteoporosis: Diabetes may lead to lower than normal bone mineral density, increasing the risk of osteoporosis. Osteoporosis is a disease in which bones become fragile and more likely to break. If not prevented or if left untreated, osteoporosis can progress painlessly until a bone breaks.
- Alzheimer's disease: Type 2 diabetes may increase the risk of Alzheimer's disease (AD). Alzheimer's disease is a progressive degenerative disease of the nervous system that leads to dementia and eventually death. The more uncontrolled blood sugar levels are, the greater the risk of developing AD. Researchers have found that cardiovascular problems caused by diabetes may contribute to dementia by blocking blood flow to the brain or causing strokes (neurological damage caused by lack of oxygen to the brain). Other possibilities are that too much insulin in the blood leads to brain-damaging inflammation, or lack of insulin in the brain deprives brain cells of glucose.
- Gastroparesis: Gastroparesis is a disorder that affects people with both type 1 and type 2 diabetes. In gastroparesis, movement of food through the stomach slows or stops completely. The muscles in the wall of the stomach work poorly or not at all, preventing the stomach from emptying properly. This can interfere with digestion and cause nausea and vomiting, problems with blood sugar control, and malnutrition.
- Depression: Studies report that individuals with diabetes have a greater risk of depression than individuals without diabetes. Causes underlying the association between depression and diabetes are unclear. Depression may develop because of stress but also may result from the metabolic effects of diabetes on the brain. Studies suggest that people with diabetes who have a history of depression are more likely to develop diabetic complications than those without depression.
- Treatment for diabetes is a lifelong commitment of monitoring blood sugar, taking insulin if prescribed, maintaining a healthy weight, eating healthy foods, and exercising regularly. The goal is to keep your blood sugar level as close to normal as possible to delay or prevent complications. In fact, tight control of blood sugar levels can reduce the risk of diabetes-related heart attacks and strokes by more than 50%.
- Lifestyle choices:
- If an individual has been diagnosed with diabetes, healthy lifestyle choices, including diet and exercise, are necessary. These healthy choices will help to improve glycemic (blood sugar) control and prevent or minimize complications of diabetes.
- Diet: A healthy diet is important in controlling blood sugar levels and preventing diabetes complications. Eat a consistent, well-balanced diet that is high in fiber, low in saturated fat, and low in concentrated sweets. A consistent diet that includes roughly the same number of calories at about the same times of day helps a healthcare provider prescribe the correct dose of medication or insulin.
- What and how much an individual eats will affect their blood sugar level. Blood sugar is typically highest one to two hours after a meal. One way individuals with diabetes can manage their food intake to keep their blood glucose as close to normal as possible is by calculating how many grams of carbohydrate they eat. Carbohydrates tend to have the greatest effect on blood glucose. The balance between the amount of carbohydrate eaten and the available insulin determines how much the blood glucose level goes up after meals or snacks. To help control your blood glucose, individuals should know which foods contain carbohydrates, the size of a "serving" of different foods, and how many carbohydrate servings to eat each day. A dietician can help individuals work out a dietary plan that is right for them.
- Foods that contain carbohydrates include grains, pasta, and rice; breads, crackers, and cereals; starchy vegetables, including potatoes, corn, peas, and winter squash; legumes such as beans, peas, and lentils; fruits and fruit juices; milk and yogurt; and sweets and desserts. Non-starchy vegetables such as spinach, kale, broccoli, salad greens, and green beans are very low in carbohydrates. Carbohydrate counting can ensure that the right amount of carbohydrate is eaten at each meal and snack.
- The amount of food an individual eats is also closely related to blood glucose control. If an individual eats more food than is recommended on a meal plan, their blood glucose goes up. Although foods containing carbohydrates have the most impact on blood glucose, most foods will have some effect.
- Exercise and weight control: Regular exercise, in any form, can help reduce the risk of developing diabetes. Physical activity moves sugar from the blood into the cells. The more active an individual is, the lower the blood sugar level. Activity can also reduce the risk of developing complications of diabetes such as heart disease, stroke, kidney failure, blindness, and leg ulcers. Exercise will also help to keep blood sugar at a relatively even level and avoid excessively low or high blood sugar levels, which can be dangerous and even life threatening. As little as 20 minutes of walking, three times a week, has a proven beneficial effect. No matter how light or how long, some exercise is better than no exercise. If the individual has complications of diabetes, such as eye, kidney, or nerve problems, they may be limited both in type of exercise and amount of exercise that can safely be performed without worsening the condition. Individuals taking insulin may need to lower the insulin dose before unusual physical activity and exercise. A doctor will help in determining these changes.
- If the individual is overweight, losing even ten pounds can reduce the risk of diabetes. To keep weight in a healthy range, it is recommended by healthcare professionals to focus on permanent changes to eating and exercise habits. A dietitian or a weight modification program can help an individual reach their goal.
- Self-monitoring blood glucose: Checking blood sugar levels frequently, at least before meals and at bedtime, is important in controlling diabetes. Even if the individual takes insulin and eats on a rigid schedule, the amount of sugar in the blood can change unpredictably. Depending on what type of insulin therapy the individual is prescribed, such as single dose injections, multiple dose injections, or an insulin pump, the individual may need to check and record blood sugar levels up to four or more times a day. Careful monitoring is the only way to make sure that the blood sugar level remains within target range. A range of 90-130 milligrams/deciliter before meals is suggested for most individuals with diabetes. A doctor will tell the individual what their target range should be.
- Also, results should be recorded in a logbook that should include insulin or oral medication doses and times, when and what was eaten, when and for how long exercise occurred, and any significant events of the day such as high or low blood sugar levels and how the problem was treated. A daily blood sugar logbook or diary is invaluable to the healthcare team in seeing how the individual is responding to medications, diet, and exercise in the treatment of their diabetes.
- Better equipment now available makes testing blood sugar levels less painful and less complicated. Medicare now pays for diabetic testing supplies, as do many private insurers and Medicaid.
- A doctor or healthcare team will help the individual decide what type of meter to buy. There are more than 20 types ofmeters available on the market. Examples include Accu-check®, Lifescan®, and OneTouch®. Meters vary in size, weight,test time, blood sample requirements, memory capabilities, and other special features. Most meterscan measure blood glucose with only a one- or two-step process.Most also incorporate no-wipe technology, which means usersdo not have to wipe off excess blood after applying a blooddrop to the reagent strip. In addition, many meters now requireonly a very small amount of blood, thus decreasing the problems with bleeding often seen in advanced diabetics and the elderly and the fear and painof wounds from the lancet.
- A few of the newer meters offer the option of obtaining bloodsamples from alternate sites, such as a forearm instead of afingertip. This can benefit patients who find constant lancetwounds on their fingers difficult to tolerate. The fingers have many nerve endings and are a very painful site for testing, although they are the most reliable. More complex meters have features to aid in identifying trendsand to graph reports for more comprehensive data tracking, particularlyfor patients who test several times a day.
- In order to get an accurate blood glucose result, the individual needs to make sure that the meter is clean, that its code matches the test strips, that their finger is clean, and that an adequate-size drop of blood is being tested. Before pricking the finger, it is recommended by healthcare professionals to wash the hands with warm water, shake the hands below the waist, and squeeze the finger a few times.
- GlucoWatch®: In 2001, the U.S. Food and Drug Administration (FDA) approved the GlucoWatch®, a watch-like device that helps individuals with diabetes measure their blood glucose via tiny electric currents. It draws small amounts of fluid from the skin and measures blood glucose levels three times per hour for up to 12 hours. The GlucoWatch® is considered a first step toward noninvasive, continuous glucose monitoring, but it does have some shortfalls. GlucoWatch® is not considered as accurate as a blood test, so any measurements that fall outside of normal ranges will need to be re-tested with a finger stick test.
- Insulin and oral medications: Many individuals with diabetes can manage their blood sugar with diet and exercise alone, but some need diabetes medications or insulin therapy. In addition to diabetes medications, a doctor might prescribe low-dose aspirin therapy to help prevent heart and blood vessel disease. Aspirin prevents blood from clotting by blocking the production of thromboxane A-2, a chemical that platelets produce that causes them to clump. Aspirin accomplishes this by inhibiting the enzyme cyclo-oxygenase-1 (COX-1) that produces thromboxane A-2.
- Many oral or injected medications can be used to treat type 2 diabetes. Some diabetes medications stimulate the pancreas to produce and release more insulin. Others inhibit the production and release of glucose from the liver, which means the individual needs less insulin to transport sugar into the cells. Still others block the action of stomach enzymes that break down carbohydrates or make tissues more sensitive to insulin.
- The decision about which medications are best depends on many factors, including blood sugar levels and the presence of any other health problems. Medications taken by mouth for diabetes and blood sugar regulation include:
- Sulfonylureas: Sulfonylureas help the pancreas make more insulin, which then lowers blood glucose. They also help the body use the insulin it makes to better lower blood glucose. For these medications to work, the pancreas has to make some insulin. Possible side effects include hypoglycemia (low blood sugar levels), an upset stomach, a skin rash or itching, and weight gain. Examples of sulfonylurea medications include glimepiride (Amaryl®), glyburide (DiaBeta®), chlorpropamide (Diabinese®), acetohexamide (Dymelor®), glipizide (Glucotrol®, Glucotrol XL®), glyburide (Glynase®, Micronase®), tolbutamide (Orinase®), and tolazamide (Tolinase®).
- Biguanides: Biguanides helps lower blood glucose by making sure the liver does not make too much glucose. Biguanides also lowers the amount of insulin in the body. Metformin (Glucophage®) is currently the only biguanide available. Individuals may lose a few pounds when starting metformin. This weight loss can help control blood glucose. Metformin can also improve blood fat and cholesterol levels, which are often not normal if the individual has type 2 diabetes. Metformin does not generally cause blood glucose to get too low (hypoglycemia), unless it is combined with other medications that increase insulin. Metformin may cause nausea and vomiting if more than about two to four alcoholic drinks a week are consumed while on the medication. Other side effects include nausea, diarrhea, headache, and weakness. A metallic taste in the mouth may be noticed.
- Alpha-glucosidase inhibitors: Alpha-glucosidase inhibitors are a class of oral medications for type 2 diabetes that decrease the absorption of carbohydrates from the intestine, resulting in a slower and lower rise in blood glucose throughout the day, especially right after meals. Before carbohydrates are absorbed from food, they must be broken down into smaller sugar particles like glucose by enzymes in the small intestine. One of the enzymes involved in breaking down carbohydrates is called alpha glucosidase. By inhibiting this enzyme, carbohydrates are not broken down as efficiently and glucose absorption is delayed. The alpha-glucosidase inhibitors include acarbose (Precose®) and miglitol (Glyset®).
- Thiazolidinediones: Thiazolidinediones help make the cells more sensitive to insulin. The insulin can then move glucose more efficiently from the blood into the cells for energy. Side effects of these medications may include weight gain, anemia (less red blood cells which causes the blood to carry less oxygen than normal), and edema (fluid accumulation). More serious side effects include liver damage and chronic heart failure. A doctor will monitor the individual's liver function while taking thiazolidinediones. Examples of thiazolidinediones includes pioglitazone (Actos®) and rosiglitazone (Avandia®).
- Meglitinides: Meglitinides helps the pancreas make more insulin right after meals, which lowers blood glucose. A doctor might prescribe a meglitinide medication by itself or with metformin (Glucophage®) if one medicine alone does not control blood glucose levels. Possible side effects of meglitinides include hypoglycemia (low blood sugar) and weight gain. Examples include repaglinide (Prandin®).
- D-phenylalanine derivative: D-phenylalanine derivatives helps the pancreas make more insulin quickly and for a short time. Then the insulin helps lower blood glucose after eating a meal. These medications may cause blood glucose levels to drop too low. Doctors will check liver function while taking d-phenylalanine derivatives. An example of a d-phenylalanine derivative is nateglinide (Starlix®).
- DPP-4 inhibitor: DPP-4 (dipeptidyl-peptidase 4) inhibitors enhance the body's own ability to control blood sugar levels, increase insulin when blood sugar is high, especially after eating, and reduce the amount of sugar made by the liver after eating. Sitagliptin (Januvia®) is currently the only DPP-4 inhibitor available. Side effects of DPP-4 inhibitors include a runny or stuffy nose, sore throat, headache, nausea, stomach pain, or diarrhea.
- Exenatide (Byetta®): Exenatide (Byetta®) is an injectable drug that reduces the level of sugar (glucose) in the blood. It is used for treating type 2 diabetes. Exenatide belongs in a class of drugs called incretin mimetics because these drugs mimic the effects of incretins. Incretins, such as human-glucagon-like peptide-1 (GLP-1), are hormones that are produced and released into the blood by the intestine in response to food. GLP-1 increases the secretion of insulin from the pancreas, slows absorption of glucose from the gut, and reduces the action of glucagon. Glucagon is a hormone that increases glucose production by the liver. All three of these actions reduce levels of glucose in the blood. In addition, GLP-1 reduces appetite. Exenatide is a synthetic (man-made) hormone that resembles and acts like GLP-1. In studies, exenatide-treated patients achieved lower blood glucose levels and experienced weight loss. Exenatide was approved by the U.S. Food and Drug Administration (FDA) in May 2005.
- Combination medications: Some anti-diabetic medications may be combined to provide glucose and insulin control. An example of a combination drug is glyburide combined with metformin (Glucovance®). Side effects of combination drugs are similar to those associated with the individual drugs in the product.
- Insulin: Insulin is a naturally-occurring hormone secreted by the pancreas. Insulin is required by the cells of the body in order for them to remove and use glucose from the blood. Insulin may need to be taken by type 1 and type 2 diabetics. Because stomach enzymes interfere with insulin taken by mouth, insulin must be injected or inhaled. Often, insulin is injected using a fine needle and syringe or an insulin pen injector (a device that looks like an ink pen, except the cartridge is filled with insulin).
- Individuals with diabetes mellitus have an inability to take up and use glucose from the blood and, as a result, the glucose level in the blood rises. In type 1 diabetes, the pancreas cannot produce insulin. Therefore, insulin therapy is needed. In type 2 diabetes, individuals produce insulin, but cells throughout the body do not respond normally to the insulin. Nevertheless, insulin also may be used in type 2 diabetes to overcome the resistance of the cells to insulin. By increasing the uptake of glucose by cells and reducing the concentration of glucose in the blood, insulin prevents or reduces the long-term complications of diabetes, including damage to the blood vessels, eyes, kidneys, and nerves. Insulin is administered by injection under the skin (subcutaneously). The subcutaneous tissue of the abdomen is preferred because absorption of the insulin is more consistent from this location than subcutaneous tissues in other locations.
- There are several types of insulin, classified by how soon and how long they act. It is helpful to know when the insulin starts to work, its peak (when the insulin is working its hardest), and the duration (how long the insulin works). Premixed combinations of slower- and fast-acting insulin are also available. Depending on the individual's needs, a doctor may prescribe a mixture of insulin types to use throughout the day and night. Insulin medications can be made from bovine, porcine, and recombinant human insulin sources. However, in the United States, bovine-tissue derived insulin is no longer available as of 1999, due to U.S. Food and Drug Administration (FDA) concerns over the possible transmission of bovine spongiform encephalopathy (also known as mad-cow disease), and most porcine derived formulations have been discontinued as well. Nearly all insulin on the market today is now produced from bacteria and is identical to human insulin.
- Regular (rapid onset of action, short duration of action) and NPH (slower onset of action, longer duration of action) human insulin are the most commonly-used preparations. Regular insulin has an onset of action (begins to reduce blood sugar) within 30 minutes of injection, reaches a peak effect at one to three hours, and has effects that last six to eight hours. NPH insulin is insulin with an intermediate duration of action. It has an onset of action starting about two hours following injection. It has a peak effect 4-12 hours after injection and aduration of action of 18-26 hours.
- Lente insulin is also insulin with an intermediate duration of action. It has an onset of action two to four hours after injection, a peak activity 6-12 hours after injection, and aduration of action of 18-26 hours. Ultralente insulin is long-acting insulin with an onset of action four to eight hours after injection, a peak effect 10-30 hours after injection, and aduration of action of more than 36 hours.
- An ultra rapid-acting insulin, insulin lispro (Humalog®), is a chemically-modified, natural insulin. When compared to regular insulin, insulin lispro has a more rapid onset of action, an earlier peak effect, and a shorter duration of action. It reaches peak activity 0.5-2.5 hours after injection. Therefore, insulin lispro should be injected 15 minutes before a meal as compared to regular insulin, which is injected 30-60 minutes before a meal.
- Insulin aspart (Novolog®) and insulin glargine (Lantus®) are both human insulins that have had their chemical composition slightly altered. The chemical changes provide insulin aspart with a faster onset of action (20 minutes) and a shorter duration of action (three to five hours) than regular human insulin. It reaches peak activity one to three hours after injection. Insulin glargine has a slower onset of action (70 minutes) and a longer duration of action (24 hours) than regular human insulin. Its activity does not peak.
- Premixed insulins are a combination of specific proportions of intermediate-acting and short-acting insulin in one bottle or insulin pen (the numbers following the brand name indicate the percentage of each type of insulin). Examples of premixed insulins include Humalog mix 75/25, Novolog 70/30, Novolin 70/30, and Humulin 70/30.
- Healthcare professionals recommend storing unopened bottles of insulin in the refrigerator; also, insulin should not be used after the expiration date. Insulin should not be frozen. Store bottles that are being used at room temperature (59-86 degrees Fahrenheit) for 28-30 days. Discard after 30 days. Avoid exposing the bottles to temperature extremes (less than 36 degrees Fahrenheit or more than 86 degrees Fahrenheit). Regular insulin should not be used if it becomes cloudy in appearance. NPH insulin should not be used if it becomes clumped or crystallized or if the bottle becomes frosted. Make sure that dosages are rechecked whenever changing insulin. Get guidance from a healthcare professional before mixing insulins.
- Insulin pump: An insulin pump also may be an option. The pump is a device about the size of a cell phone worn on the outside of the body. A tube connects the reservoir of insulin to a catheter that is inserted under the skin of the abdomen. The pump is programmed to dispense specific amounts of insulin automatically. It can be adjusted to deliver more or less insulin depending on meals, activity level, and blood sugar level.
- Inhaled insulin: Inhaled insulin (Exubera®) is also available. Inhaled insulin is a powdered form of insulin that is rapid acting, usually taken before a meal. It replaces only short-acting forms of injectable insulin, not the longer acting (basal) insulin that may be required as part of a diabetes treatment plan. Inhaled insulin is not approved for anyone younger than 18 and should not be used by individuals who smoke or who have given up cigarettes within the past six months. However, it is considered safe for individuals who live with smokers. Exubera® is not recommended for individuals with asthma, bronchitis, emphysema, or any form of active lung disease. Baseline tests for lung function are recommended by healthcare providers before starting treatment, after the first six months of treatment, and every year thereafter, even if no pulmonary symptoms such as lung or breathing problems exist.
- Pancreas transplant: Many individuals with type 1 diabetes can manage their disease by following a diet and exercise plan, monitoring blood glucose levels, and using insulin injections. But for some individuals, this is a difficult task, resulting in a number of serious short- and long-term complications. A pancreas transplant is the closest thing to restoring normal pancreas function. A pancreas transplant is not the best option for all people with type 1 diabetes, however, and is primarily recommended for individuals with kidney failure.
- Pancreas transplants pose serious health risks and are not always successful. The individual will need to take immune-suppressing drugs, such as cyclosporine (Sandimmune®), to prevent organ rejection. These drugs can have serious side effects, including a high risk of infection and organ injury. Because the side effects can be more dangerous than the diabetes, pancreas transplants are usually reserved for individuals whose diabetes cannot be controlled or those who have serious complications.
- Other surgeries: Islet transplantation is an experimental procedure where islets (special cells in the pancreas that make insulin) are taken from the pancreas of a deceased healthy organ donor. The islets are purified, processed, and transferred into the individual with type 1 diabetes. Once implanted, the beta cells in these islets begin to make and release insulin. Researchers hope that islet transplantation will help people with type 1 diabetes live without daily injections of insulin. Stem cell transplants may also offer help to those suffering from type 1 diabetes, but the benefits are controversial in the United States.
|The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.