Diabetes Mellitus (Type 1 and Type 2)

Diabetes has emerged as one of the fastest growing health challenges, and the number of adults living with diabetes has tripled in the world over the past two decades. About 537 million adults (20-79 years) worldwide have diabetes. China has the highest number of diabetes cases worldwide, with around 141 million people being affected, followed by India and Pakistan. The United States has more than 38 million people with diabetes.

• Diabetes affects approximately 38.4 million people in the United States, while another estimated 97.6 million people have prediabetes.
• An estimated 8.7 million people in the United States have diabetes and don't even know it.
• Medical expenses for people with diabetes are over two times higher than those for people who do not have diabetes. These numbers reflect only the population in the United States. Globally, the statistics are staggering.
• Diabetes is the 8th leading cause of death in the United States.

Why is diabetes increasing in the United States?

The reason diabetes is increasing in the US can be attributed to various factors including:

• Obesity
• Lack of physical activity
• Quantitative and qualitative changes in diet
• Awareness
• Change in diagnostic criteria and diagnosis
• Aging population

There are two major types of diabetes, called type 1 and type 2. In type 1 diabetes, formerly called insulin-dependent diabetes mellitus (IDDM), or juvenile-onset diabetes mellitus, the pancreas undergoes an autoimmune attack by the body itself and is rendered incapable of making insulin. Abnormal antibodies have been found in the majority of patients with type 1 diabetes. Antibodies are proteins in the blood that are part of the body's immune system. Patients with type 1 diabetes must rely on insulin medication for survival.

In autoimmune diseases, such as type 1 diabetes, the immune system mistakenly manufactures antibodies and inflammatory cells that are directed against and cause damage to patients' own body tissues. In persons with type 1 diabetes, the beta cells of the pancreas, which are responsible for insulin production, are attacked by the misdirected immune system. It is believed the tendency to develop abnormal antibodies in type 1 diabetes is, in part, genetically inherited, though the details are not fully understood.

Exposure to certain viral infections (such as mumps and Coxsackie viruses) or other environmental toxins may serve to trigger abnormal antibody responses that cause damage to the pancreas cells where insulin is made. Some of the antibodies seen in type 1 diabetes include anti-islet cell antibodies, anti-insulin antibodies, and anti-glutamic decarboxylase antibodies. These antibodies can be detected in the majority of patients and may help determine which individuals are at risk for developing type 1 diabetes.

At present, the American Diabetes Association does not recommend general screening of the population for type 1 diabetes, though screening of high-risk individuals, such as those with a first-degree relative (sibling, parent, child) with type 1 diabetes are encouraged. Type 1 diabetes tends to occur in young, lean individuals, usually before 30 years of age; however, older patients do present with this form of diabetes on occasion. This subgroup is referred to as latent autoimmune diabetes in adults (LADA). LADA is a slow, progressive form of type 1 diabetes. Of all the people with diabetes, only approximately 10% have type 1 diabetes and the remaining 90% have type 2 diabetes.

Type 2 diabetes was also previously referred to as non-insulin-dependent diabetes mellitus (NIDDM), or adult-onset diabetes mellitus (AODM). In type 2 diabetes, patients can still produce insulin but do so relatively inadequately for their body's needs, particularly in the face of insulin resistance as discussed above. In many cases, this actually means the pancreas produces larger than normal quantities of insulin. A major feature of type 2 diabetes is a lack of sensitivity to insulin by the cells of the body (particularly fat and muscle cells).

In addition to the problems with an increase in insulin resistance, the release of insulin by the pancreas may also be defective and suboptimal. There is a known steady decline in beta cell production of insulin in type 2 diabetes that contributes to worsening glucose control. (This is a major factor for many patients with type 2 diabetes who ultimately require insulin therapy.) Finally, the liver in these patients continues to produce glucose through a process called gluconeogenesis despite elevated glucose levels. The control of gluconeogenesis becomes compromised.

Type 2 diabetes occurs mostly in individuals over 30 years old and the incidence increases with age, but an alarming number of patients with type 2 diabetes are barely in their teen years. Most of these cases are a direct result of poor eating habits, higher body weight, and lack of exercise.

While there is a strong genetic component to developing this form of diabetes, there are other risk factors - the most significant of which is obesity. There is a direct relationship between the degree of obesity and the risk of developing type 2 diabetes, and this holds true in children as well as adults. It is estimated the chance to develop type 2 diabetes doubles for every 20% increase over desirable body weight. The U.S. Preventive Services Task Force (USPSTF) recommends screening for prediabetes and type 2 diabetes in adults aged 35 to 70 years who have overweight or obesity.

Regarding age, data shows that for each decade after 40 years of age regardless of weight there is an increase in the incidence of diabetes. The prevalence of diabetes in persons 65 years of age and older is around 29%. Type 2 diabetes is also more common in certain ethnic groups.

Gestational diabetes

Gestational diabetes is diabetes that occurs temporarily during pregnancy, and reports suggest that it occurs in 2% to 10% of all pregnancies. Significant hormonal changes during pregnancy can lead to blood sugar elevation in genetically predisposed individuals. Gestational diabetes usually resolves once the baby is born but 35% to 60% of women with gestational diabetes will eventually develop type 2 diabetes over the next 10 to 20 years, especially in those who require insulin during pregnancy and those who remain overweight after their delivery. Women with gestational diabetes are usually asked to undergo an oral glucose tolerance test about six weeks after giving birth to determine if their diabetes has persisted beyond the pregnancy, or if any evidence (such as impaired glucose tolerance) is present that may be a clue to a risk for developing diabetes.

Secondary diabetes

"Secondary" diabetes refers to elevated blood sugar levels from another medical condition. Secondary diabetes may develop when the pancreatic tissue responsible for the production of insulin is destroyed by diseases, such as chronic pancreatitis (inflammation of the pancreas by toxins like excessive alcohol), trauma, or surgical removal of the pancreas.

Hormonal disturbances

Diabetes can also result from other hormonal disturbances, such as excessive growth hormone production (acromegaly) and Cushing's syndrome. In acromegaly, a pituitary gland tumor at the base of the brain causes excessive production of growth hormone, leading to hyperglycemia. In Cushing's syndrome, the adrenal glands produce an excess of cortisol, which promotes blood sugar elevation.

Medications

Certain medications may worsen diabetes control, or "unmask" latent diabetes. This is seen most commonly when steroid medications (such as prednisone) are taken and also with medications used in the treatment of HIV/AIDS infection.

Insufficient production of insulin (either absolutely or relative to the body's needs), production of defective insulin (uncommon), or the inability of cells to use insulin properly and efficiently leads to high blood sugar levels (hyperglycemia) and diabetes.

• This latter condition affects mostly the cells of muscle and fat tissues and results in a condition known as insulin resistance. This is the primary problem in type 2 diabetes.
• The absolute lack of insulin, usually secondary to a destructive process affecting the insulin-producing beta cells in the pancreas, is the main disorder in type 1 diabetes.

In type 2 diabetes, there also is a steady decline of beta cells that adds to the process of elevated blood sugars. Essentially, if someone is resistant to insulin, the body can, to some degree, increase the production of insulin and overcome the level of resistance. After a time, if production decreases and insulin cannot be released as vigorously, hyperglycemia develops.

What is glucose?

Glucose is a simple sugar found in food that is an essential nutrient that provides energy for the proper functioning of the body cells. Carbohydrates are broken down in the small intestine and the glucose in digested food is then absorbed by the intestinal cells into the bloodstream and is carried by the bloodstream to all the cells in the body where it is utilized. However, glucose cannot enter the cells alone and needs insulin to aid in its transport into the cells. Without insulin, the cells become starved of glucose energy despite the presence of abundant glucose in the bloodstream. The abundant, unutilized glucose is excreted in the urine.

What is insulin?

Insulin is a hormone produced by specialized cells (beta cells) of the pancreas, a deep-seated organ in the abdomen located behind the stomach. In addition to helping glucose enter the cells, insulin is also important in tightly regulating the level of glucose in the blood. After a meal, the blood glucose level rises. In response to the increased glucose level, the pancreas normally releases more insulin into the bloodstream to help glucose enter the cells and lower blood glucose levels after a meal. When the blood glucose levels are lowered, the insulin release from the pancreas is turned down. Even in the fasting state there is a low steady release of insulin than fluctuates a bit and helps to maintain a steady blood sugar level during fasting. In normal individuals, this regulatory system helps keep blood glucose levels in a tightly controlled range. But in patients with diabetes, insulin is either absent, insufficient for the body's needs, or not used properly by the body. All of these factors cause elevated levels of blood glucose (hyperglycemia).

Risk factors for type 1 diabetes are not as well understood as those for type 2 diabetes. Family history is a known risk factor for type 1 diabetes. Other risk factors can include having certain infections or diseases of the pancreas.

Risk factors for developing type 2 diabetes and prediabetes include:

• Being obese or overweight
• High blood pressure
• Elevated levels of triglycerides and low levels of "good" cholesterol (HDL)
• Sedentary lifestyle
• Family history
• Increasing age
• Polycystic ovary syndrome (PCOS)
• Impaired glucose tolerance
• Insulin resistance
• Dietary factors: A meal plan high in fat and lacking fiber can increase the probability of type 2 diabetes
• Gestational diabetes during pregnancy
• Ethnic background: Hispanic/Latino Americans, African-Americans, Native Americans, Asian-Americans, Pacific Islanders, and Alaska natives are at greater risk

Is diabetes a hereditary or genetic disease? Is diabetes inherited from mother or father?

Diabetes is a hereditary disease, which means a child of a person who is diabetic is at higher risk of developing diabetes compared to the general population at the given age. Diabetes can be inherited from either parent.

The child’s risk increases:

• If the father has type 1 diabetes, the risk of the child developing diabetes is 1 in 17.
• If the mother has type 1 diabetes and:
  • The child was born before she is 25 years old, then the risk is 1 in 25.
  • The child was born after she is 25 years old, the child’s risk is 1 in 100.
• If the father and mother develop diabetes before the age of 11 years, the child’s risk is between 1 in 10 and 1 in 4, respectively.
• If a parent has diabetes along with thyroid disease, poorly working adrenal gland, and immune system disorder, the child's risk of developing type 1 diabetes is 1 in 2.

Even if diabetes runs in families, it is possible to delay or prevent type 2 diabetes in children or youth by following a healthy lifestyle.

Type 2 diabetes can result from a combination of genetic and environmental factors. The risk of developing type 2 diabetes is higher in kids if the mother rather than father has diabetes.

• If the father has type 2 diabetes, the risk factor is about 30%.
• If the mother has type 2 diabetes, the risk factor is slightly higher.
• If both parents have diabetes, the risk factor increases to about 70%.

Mutation in any gene involved in controlling glucose levels can increase the risk of type 2 diabetes, which include genes that control:

• The production of glucose
• The production and regulation of insulin
• How glucose levels are sensed in the body

Genes associated with type 2 diabetes risk include:

• TCF7L2, which affects insulin secretion and glucose production
• ABCC8, which helps regulate insulin
• CAPN10, which is associated with type 2 diabetes risk in Mexican-Americans
• GLUT2, which helps move glucose into the pancreas
• GCGR, a glucagon hormone involved in glucose regulation

Early symptoms of untreated diabetes are related to elevated blood sugar levels and loss of glucose in the urine. High amounts of glucose in the urine can cause increased urine output (frequent urination) and lead to dehydration. Dehydration also causes increased thirst and water consumption.

The symptoms of diabetes are as follows:

• Fatigue: Feeling exhausted all the time despite adequate sleep.
• Polyphagia: Hunger despite regular meals. Irritability if you skip a meal.
• Weight loss: A weight loss of around 9-18 pounds (four to eight kg) for no apparent reason is another symptom of high blood sugar levels.
• Yeast infections: Vaginal thrush presenting as curdy white vaginal discharge in women and balanitis or itching at the tip of the penis in men may be an early marker of diabetes.
• Feeling thirsty: Increased thirst despite drinking adequate water.
• Increased urination: Peeing often, especially at night, is a warning sign of diabetes.
• Tingling and numbness in the legs: If you have constant pins- and needle-like sensation or burning sensation in your soles, high blood sugars may be the culprit.
• Frequent infections (such as infections of the bladder, skin, and vaginal areas) are more likely to occur in people with untreated or poorly-controlled diabetes.

Diabetes may present without signs and symptoms for a long time. Routine screening of blood sugars, in case you have risk factors, is very important.

Many people are unaware they have diabetes, especially in its early stages when symptoms may not be present.

There is no definite way to know if you have diabetes without blood tests to determine blood glucose levels (see the section on Diagnosis of diabetes).

See your doctor if you have symptoms of diabetes or if you are concerned about your diabetes risk.

The fasting blood glucose (sugar) test is the preferred way to diagnose diabetes. It is easy to perform and convenient. After a person has fasted overnight (at least 8 hours), a single sample of blood is drawn and sent to the laboratory for analysis. This can also be done accurately in a doctor's office using a glucose meter.

• Normal fasting plasma glucose levels are less than 100 milligrams per deciliter (mg/dl).
• Fasting plasma glucose levels of more than 126 mg/dl on two or more tests on different days indicate diabetes.
• A random blood glucose test can also be used to diagnose diabetes. A blood glucose level of 200 mg/dl or higher indicates diabetes.

When fasting blood glucose stays above 100mg/dl, but in the range of 100-126mg/dl, this is known as impaired fasting glucose (IFG). While patients with IFG or prediabetes do not have the diagnosis of diabetes, this condition carries with it its own risks and concerns and is addressed elsewhere.

The oral glucose tolerance test

Though not routinely used any longer, the oral glucose tolerance test (OGTT) is a gold standard for making the diagnosis of type 2 diabetes. It is still commonly used for diagnosing gestational diabetes and in conditions of pre-diabetes, such as polycystic ovary syndrome. With an oral glucose tolerance test, a person fasts overnight (at least eight but not more than 16 hours). Then first, the fasting plasma glucose is tested. After this test, the person receives an oral dose (75 grams) of glucose.

The classic oral glucose tolerance test measures blood glucose levels five times over a period of three hours. Some physicians simply get a baseline blood sample followed by a sample two hours after drinking the glucose solution. In a person without diabetes, the glucose levels rise and then fall quickly. In someone with diabetes, glucose levels rise higher than normal and fail to come back down as fast.

Evaluating the results of the oral glucose tolerance test

Glucose tolerance tests may lead to one of the following diagnoses:

• Normal response: A person is said to have a normal response when the 2-hour glucose level is less than 140 mg/dl, and all values between 0 and 2 hours are less than 200 mg/dl.
• Impaired glucose tolerance (prediabetes): A person is said to have impaired glucose tolerance when the fasting plasma glucose is less than 126 mg/dl and the 2-hour glucose level is between 140 and 199 mg/dl.
• Diabetes: A person has diabetes when two diagnostic tests done on different days show that the blood glucose level is high.
• Gestational diabetes: A pregnant woman has gestational diabetes when she has any two of the following:
  • a fasting plasma glucose of 92 mg/dl or more,
  • a 1-hour glucose level of 180 mg/dl or more, or
  • a 2-hour glucose level of 153 mg/dl, or more.

Home blood sugar (glucose) testing is an important part of controlling blood sugar. One important goal of diabetes treatment is to keep blood glucose levels near the normal range of 70 to 120 mg/dl before meals and under 140 mg/dl two hours after eating. Blood glucose levels are usually tested before and after meals, and at bedtime. The blood sugar level is typically determined by pricking a fingertip with a lancing device and applying the blood to a glucose meter, which reads the value. The test results are then used to help patients make adjustments in medications, diets, and physical activities.

Continuous glucose sensor systems involve an implantable cannula placed just under the skin in the abdomen or in the arm. This cannula allows for frequent sampling of blood glucose levels. Attached to this is a transmitter that sends the data to a pager-like device or an app on your cell phone. This allows the wearer to see not only the current glucose reading but also the graphic trends. In some devices, the rate of change in blood sugar is also shown. There are alarms for low and high sugar levels. These sensor systems may interface with insulin pumps to deliver the appropriate dose of insulin in devices known as automated insulin-delivery systems or artificial pancreas systems.

Hemoglobin A1c (HBA1c)

To explain what hemoglobin A1c is, think in simple terms. When sugar in the blood sticks to hemoglobin proteins red blood cells, it is known as glycosylated hemoglobin or hemoglobin A1c (HBA1c). Measurement of HBA1c gives us an idea of how much sugar is present in the bloodstream for the preceding three months, since red blood cells live for about 3 months. In most labs, the normal range is 4%-5.9 %. In poorly controlled diabetes, it's 8.0% or above, and in well-controlled patients, it's less than 7.0% (optimal is less than 6.5%). The benefit of measuring A1c is that it gives a more reasonable and stable view of what's happening over the course of time (three months), and the value does not vary as much as finger stick blood sugar measurements. There is a direct correlation between A1c levels and average blood sugar levels as follows.

While there are no guidelines to use A1c as a screening tool, it gives a physician a good idea that someone is diabetic if the value is elevated. Right now, it is used as a standard tool to determine blood sugar control in patients known to have diabetes.

The American Diabetes Association currently recommends an A1c goal of less than 7.0% with an A1C goal for selected individuals as close to normal as possible (less than 6%) without significant hypoglycemia. Other groups such as the American Association of Clinical Endocrinologists feel an A1c of less than 6.5% should be the goal.

Studies have also shown there is about a 35% decrease in relative risk for microvascular disease for every 1% reduction in A1c. The closer to normal the A1c, the lower the absolute risk for microvascular complications.

There are a number of other conditions aside from diabetes in which an A1c value may not be accurate. For example, with significant anemia, the red blood cell count is low, and thus the A1c is altered. This may also be the case in sickle cell disease and other hemoglobinopathies.

1. Severely elevated blood sugar levels due to an actual lack of insulin or a relative deficiency of insulin.
2. Abnormally low blood sugar levels due to too much insulin or other glucose-lowering medications.

Acute complications of type 2 diabetes

In patients with type 2 diabetes, stress, infection, and medications (such as corticosteroids) can also lead to severely elevated blood sugar levels. Accompanied by dehydration, severe blood sugar elevation in patients with type 2 diabetes can lead to an increase in blood osmolality (hyperosmolar state), which is the concentration of chemical and mineral particles in the blood. This condition can worsen and lead to coma (hyperosmolar coma). A hyperosmolar coma is most common in elderly patients with type 2 diabetes. Like diabetic ketoacidosis, a hyperosmolar coma is a medical emergency. Immediate treatment with intravenous fluid and insulin is important in reversing the hyperosmolar state. Unlike patients with type 1 diabetes, patients with type 2 diabetes do not generally develop ketoacidosis solely on the basis of their diabetes. In general, type 2 diabetes occurs in an older population, so concomitant medical conditions are more likely to be present, and these patients may actually be sicker overall. The complication and death rates from hyperosmolar coma are thus higher than in diabetic ketoacidosis.

Hypoglycemia means abnormally low blood sugar (glucose). In patients with diabetes, the most common cause of low blood sugar is excessive use of insulin or other glucose-lowering medications to lower the blood sugar level in diabetic patients in the presence of a delayed or absent meal. When low blood sugar levels occur because of too much insulin it is called an insulin reaction. Sometimes, low blood sugar can be the result of an insufficient caloric intake or sudden excessive physical exertion.

Blood glucose is essential for the proper functioning of brain cells and low blood sugar can lead to central nervous system symptoms such as:

• dizziness,
• confusion,
• sweating,
• trouble speaking,
• weakness, and
• tremors.

The actual level of blood sugar at which these symptoms occur varies with each person, but usually it occurs when blood sugars are less than 50 mg/dl. Untreated, severely low blood sugar levels can lead to coma, seizures, and, in the worst-case scenario, irreversible brain death.

The treatment of low blood sugar consists of administering a quickly absorbed glucose source including glucose-containing drinks, such as orange juice, soft drinks (not sugar-free), or glucose tablets in doses of 15-20 grams at a time (for example, the equivalent of half a glass of juice). Even cake frosting applied inside the cheeks can work in a pinch if patient cooperation is difficult. If the individual becomes unconscious, glucagon can be given by intramuscular injection.

Glucagon is a hormone that causes the release of glucose from the liver (for example, it promotes gluconeogenesis). Glucagon can be lifesaving and every patient with diabetes who has a history of hypoglycemia (particularly those on insulin) should have a glucagon kit. Families and friends of those with diabetes need to be taught how to administer glucagon since patients will not be able to do it themselves in an emergency situation. Another lifesaving device that should be mentioned is very simple; a medic-alert bracelet should be worn by all patients with diabetes.

Acute complications of type 1 diabetes

Insulin is vital to patients with type 1 diabetes - they cannot live without a source of external (exogenous) insulin. Without insulin, patients with type 1 diabetes develop severely elevated blood sugar levels. This leads to increased urine glucose, which in turn leads to excessive loss of fluid and electrolytes in the urine. Lack of insulin also causes the inability to store fat and protein along with a breakdown of existing fat and protein stores. This dysregulation results in the process of ketosis and the release of ketones into the blood. Ketones turn the blood acidic, a condition called diabetic ketoacidosis (DKA). Symptoms of diabetic ketoacidosis include nausea, vomiting, and abdominal pain. Without prompt medical treatment, patients with diabetic ketoacidosis shock, coma, and even death can rapidly occur.

Diabetic ketoacidosis can be caused by infections, stress, or trauma, all of which may increase insulin requirements. In addition, missing doses of insulin is also an obvious risk factor for developing diabetic ketoacidosis. Urgent treatment of diabetic ketoacidosis involves the intravenous administration of fluid, electrolytes, and insulin, usually in a hospital intensive care unit. Dehydration can be very severe, and it is not unusual to need to replace 6-7 liters of fluid when a person presents with diabetic ketoacidosis. Antibiotics are given for infections. With treatment, abnormal blood sugar levels, ketone production, acidosis, and dehydration can be reversed rapidly, and patients can recover remarkably well.

These diabetes complications are related to blood vessel diseases and are generally classified into small vessel diseases, such as those involving the eyes, kidneys, and nerves (microvascular disease), and large vessel diseases involving the heart and blood vessels (macrovascular disease). Diabetes accelerates the hardening of the arteries (atherosclerosis) of the larger blood vessels, leading to coronary heart disease (angina or heart attack), strokes, and pain in the lower extremities because of a lack of blood supply (claudication).

Eye Complications

The major eye complication of diabetes is called diabetic retinopathy. Diabetic retinopathy occurs in patients who have had diabetes for at least five years. Diseased small blood vessels in the back of the eye cause the leakage of protein and blood in the retina. Disease in these blood vessels also causes the formation of small aneurysms (microaneurysms), and new but brittle blood vessels (neovascularization). Spontaneous bleeding from the new and brittle blood vessels can lead to retinal scarring and retinal detachment, thus impairing vision.

To treat diabetic retinopathy, a laser is used to destroy and prevent the recurrence of the development of these small aneurysms and brittle blood vessels. Worldwide, approximately 50% of patients with diabetes will develop some degree of diabetic retinopathy after 10 years of diabetes, and 80% after 15 years of the disease. Poor control of blood sugar and blood pressure further aggravates eye disease in diabetes.

Cataracts and glaucoma are also more common among diabetics. Since the lens of the eye lets water through, if blood sugar concentrations vary a lot, the lens of the eye will shrink and swell with fluid accordingly. As a result, blurry vision is very common in poorly controlled diabetes. Patients are usually discouraged from getting a new eyeglass prescription until their blood sugar is controlled. This allows for a more accurate assessment of what kind of prescription lens is required.

Kidney Damage

Kidney damage from diabetes is called diabetic nephropathy. The onset of kidney disease and its progression are extremely variable. Initially, diseased small blood vessels in the kidneys cause the leakage of protein in the urine. Later on, the kidneys lose their ability to cleanse and filter blood. The accumulation of toxic waste products in the blood leads to the need for dialysis. Dialysis involves using a machine that serves the function of the kidney by filtering and cleaning the blood. In some patients who do not want to undergo chronic dialysis, kidney transplantation may be considered.

The progression of nephropathy in patients can be significantly slowed by controlling high blood pressure and by aggressively treating high blood sugar levels.

Nerve Damage

Nerve damage from diabetes is called diabetic neuropathy and is also caused by disease of small blood vessels. In diabetes, the blood flow to the nerves is limited, leaving the nerves without blood flow, and they get damaged or die as a result (a term known as ischemia). Symptoms of diabetic nerve damage include numbness, burning, and aching of the feet and lower extremities. When the nerve disease causes a complete loss of sensation in the feet, patients may not be aware of injuries to the feet, and fail to properly protect them. Shoes or other protection should be worn as much as possible. Even seemingly minor skin injuries should be attended to promptly to avoid serious infections. Because of poor blood circulation, diabetic foot injuries may not heal. Sometimes, minor foot injuries can lead to serious infection, ulcers, and even gangrene, necessitating surgical amputation of toes, feet, and other infected parts.

Diabetic nerve damage can affect the nerves that are important for penile erection, causing erectile dysfunction (ED, impotence). Erectile dysfunction can also be caused by poor blood flow to the penis from diabetic blood vessel disease.

Diabetic neuropathy can also affect nerves in the stomach and intestines, causing nausea, weight loss, diarrhea, and other symptoms of gastroparesis (delayed emptying of food contents from the stomach into the intestines, due to ineffective contraction of the stomach muscles).

The pain of diabetic nerve damage may respond to traditional treatments with certain medications such as gabapentin (Neurontin), phenytoin (Dilantin), and carbamazepine (Tegretol) traditionally used in the treatment of seizure disorders. Amitriptyline (Elavil, Endep) and desipramine (Norpramin) are medications traditionally used for depression. While many of these medications are not indicated specifically for the treatment of diabetes-related nerve pain, they are used by physicians commonly. Newer medications for nerve pain include pregabalin (Lyrica) and duloxetine (Cymbalta).

The pain of diabetic nerve damage may also improve with better blood sugar control, though unfortunately blood glucose control and the course of neuropathy do not always go hand in hand.

Aggressive and intensive control of elevated levels of blood sugar in patients with type 1 and type 2 diabetes decreases the complications of nephropathy, neuropathy, retinopathy, and may reduce the occurrence and severity of large blood vessel diseases. Aggressive control with intensive therapy means achieving fasting glucose levels between 70-120 mg/dl; glucose levels of less than 160 mg/dl after meals; and near normal hemoglobin A1c levels.

Studies in type 1 patients have shown that in intensively treated patients, diabetic eye disease decreased by 76%, kidney disease decreased by 54%, and nerve disease decreased by 60%. More recently the EDIC trial has shown type 1 diabetes is also associated with increased heart disease, similar to type 2 diabetes. However, the price for aggressive blood sugar control is a two to threefold increase in the incidence of abnormally low blood sugar levels (caused by diabetes medications). For this reason, tight control of diabetes to achieve glucose levels between 70 to120 mg/dl is not recommended for children under 13 years of age, patients with severe recurrent hypoglycemia, patients unaware of their hypoglycemia, and patients with far advanced diabetes complications. To achieve optimal glucose control without an undue risk of abnormally lowering blood sugar levels, patients with type 1 diabetes must monitor their blood glucose at least four times a day and administer insulin at least three times per day. In patients with type 2 diabetes, aggressive blood sugar control has similar beneficial effects on the eyes, kidneys, nerves, and blood vessels.

The prognosis of diabetes is related to the extent to which the condition is kept under control to prevent the development of the complications. Some of the more serious complications of diabetes such as kidney failure and cardiovascular disease can be life-threatening. Acute complications such as diabetic ketoacidosis can also be life-threatening. Aggressive control of blood sugar levels can prevent or delay the onset of complications, and many people with diabetes lead long and full lives.