Diabetes - Treatment and Prevention
- Types of diabetes
- Risk factors
- Etiology and pathology
- Symptoms and diagnosis
- Complications of diabetes
- Management/treatment options
Types of diabetes
There are three major types of diabetes, and a condition known as pre-diabetes:
Type I (or insulin-dependent diabetes, also called juvenile-onset diabetes). Type 1 diabetes is an autoimmune disease where the immune system attacks the insulin-producing beta cells in the pancreas and destroys them. The pancreas then produces little or no insulin.
Sc ientists currently do not know exactly what causes the body's immune system to attack the beta cells, but they believe that autoimmune, genetic, and environmental factors are involved. Type 1 diabetes accounts for about 5 to 10 percent of diagnosed diabetes in Canada and the United States.
Although Type 1 diabetes develops most often in children and young adults, the disorder can appear at any age. The symptoms of Type 1 diabetes usually develop over a short period, although the destruction of beta cells can begin years earlier.
Type 2, (or non insulin-dependent diabetes, also called adult-onset diabetes). This is the most common form of diabetes. About 90 to 95 percent of people with diabetes have Type 2. This form of diabetes usually develops in adults age 40 and older and is most common in adults over age 55. Close to 80 percent of people with Type 2 diabetes are overweight. Type 2 diabetes is often part of a metabolic syndrome that includes obesity, elevated blood pressure, and high levels of blood lipids. As more children and adolescents become overweight, Type 2 diabetes is becoming more common in young people.
When Type 2 diabetes is diagnosed, the pancreas is usually producing insulin but, for unknown reasons, the body cannot effectively use this insulin. After several years, the production of insulin decreases. The result is the same as with Type 1 diabetes - the cells cannot make proper use of the glucose, and it accumulates in the blood.
The symptoms of Type 2 diabetes develop gradually. Some patients will have no symptoms at all.
Gestational Diabetes develops only during pregnancy. Although it usually disappears after delivery, the mother is at increased risk of getting Type 2 diabetes later in life. Gestational diabetes affects about 4 percent of all pregnant women
Pre-diabetes is a condition that occurs when a person's blood glucose levels are higher than normal but not high enough for a diagnosis of Type 2 diabetes. Almost the same number of people have pre-diabetes as have the disease itself.
Risk factors
Certain factors can increase the risk of developing diabetes.
Type 1 diabetes occurs equally among males and females, but is more common in Caucasians. Some northern European countries, including Finland and Sweden, have high rates of Type 1 diabetes. The condition is rare in most African, American Indian, and Asian populations. The reasons for these differences are not known.
Even when insulin is injected regularly, Type 1 diabetes usually results in a drastic reduction in the quality of life and shortens life expectancy by an average of 15 years.
Type 2 diabetes occurs most often in people over 40, particularly those who are overweight. It is more prevalent among Blacks, Aboriginal peoples, Asian and Pacific Islanders and Hispanics. Native peoples have the highest rates of diabetes in the world. Canadian Aboriginal children are now being diagnosed with Type 2 diabetes. Although diabetes in Inuits is not as prevalent as in other Aboriginal populations, significant increases are being seen among Inuits too. The incidence of diabetes in Canada is likely to increase for several reasons. First, a large segment of the population is aging. Also, minority groups with higher risk for diabetes are among the fastest-growing segments of the Canadian population.
Other risk factors for diabetes include:
- obesity (especially if the excess weight is carried in the midsection)
- sedentary lifestyle (individuals who expend less than 1.5 kilocalories per kg or less per day are considered sedentary).
- over the age of 45
- smoker
- high cholesterol and other blood lipids
- elevated blood pressure
- giving birth to a large baby (over 9 lb. or 4 kg.)
- blood relative of a person with diabetes (sibling, parent)
Etiology and pathology
Type 1 diabetes is caused by a highly selective destruction of the beta cells. This destruction appears to be the result of an ongoing autoimmune attack. The beta cells become depleted as no compensatory regeneration occurs. It is not known why this occurs.
The etiology of Type 2 diabetes is not known, but several analyses suggest that the disorder results from a combination of genetic susceptibility and external/environmental factors. These may cause the beta cells to produce a reduced amount of insulin and/or a decrease of insulin-mediated uptake of glucose in the peripheral tissues. External factors include reduced physical activity and an increase in calorie consumption, especially fat. The impact of the reduced physical activity and the excessive caloric consumption on the development of Type 2 diabetes is the basis for the significant global increase in the prevalence of this form of the disease.
Symptoms and diagnosis
The symptoms of diabetes include:
- elevated sugar levels in the urine and blood
- polyuria
- increased thirst and/or hunger
- weakness/fatigue
- weight loss
- blurred vision
A diagnosis may be made when
- any of these symptoms accompany a casual plasma glucose value of greater than 11.1 mmol/L, or
- a fasting (no caloric intake for at least 6 hours) plasma glucose test is greater than 7.0 mmol/L, or
- a plasma glucose value in the 2-hour sample (2hrPG) of the oral glucose tolerance test (OGTT) is greater than 11.1 mmol/L.
Prolonged hyperglycemia leads to increased protein and fat catabolism - a condition that can cause premature vascular degeneration, arteriosclerosis, and several other complications.
Approximately 50 percent of people with Type 2 diabetes are asymptomatic and are diagnosed incidentally. Undiagnosed/untreated, diabetes may lead to severe complications.
Complications of diabetes
The complications of Type 1 and Type 2 diabetes are related to high blood glucose levels and correlate with the duration of the diabetes. They include microvascular changes associated with retinopathy, nephropathy and neuropathy; dermopathy, peripheral vascular disease and coronary artery disease.
Retinopathy
The progressive damage to the eye's retina caused by long-term diabetes is the leading cause of blindness in North Americans of working age.
The incidence and severity of the retinopathy increases with the duration of diabetes and is likely to be worse if diabetes management is poor or lacking. (After 20 years of diabetes, nearly all patients with Type 1 diabetes and 60 percent of patients with Type 2 diabetes have some degree of retinopathy.)
Excessive blood flow and blood pressure within the small blood vessels in the retina creates an environment that is highly likely to cause damage. The damaged vessels may leak blood and fluid into the surrounding tissues and cause visual loss. In the earlier and less severe type (non-proliferative diabetic retinopathy) the existing blood vessels become porous and leak fluid into the retina, causing blurred vision. In the more advanced and severe type (proliferative retinopathy), new growth of blood vessels occurs within the eye. These new vessels are fragile and can hemorrhage causing loss of vision.
Nephropathy
Diabetic nephropathy is a kidney disorder characterized by proteinuria and progressive reduction in kidney function due to destruction of the glomeruli. It is the most common cause of chronic renal failure and end stage renal disease.
Roughly 40 percent of people with Type 1 diabetes, and 30 percent of people with Type 2 diabetes, will eventually develop end-stage renal disease. Again, the risk is higher if glucose is poorly controlled than if the glucose level is well controlled.
The mechanism that causes diabetic nephropathy is unknown.
Neuropathy
The nerve cells are vulnerable due to their length/shape. Each nerve is dependent on the thousands of microvessels along its path to receive oxygen, fuel, and other nutrients. If one or more of these supporting microvessels become damaged, that part of the nerve is also damaged. The long nerves going to the feet are the first to be damaged when neuropathy occurs. The conduction of nerve impulses is partially dependent on the outer myelin sheath, which is also vulnerable to damage from high blood sugars.
Significant clinical neuropathy can develop within the first 10 years following diagnosis of diabetes and the risk of nerve damage increases with time. Some studies suggest that up to 60 percent of people with diabetes have some degree of nerve damage.
Nerve damage may manifest as:
- loss of the ability to sweat. This can cause dry skin, callus buildup, pain, tingling, burning, and numbness that starts in the feet and slowly progress up the calves.
- loss of tendon reflex and sense of vibration.
- inability to detect excessive heat.
- inability to detect objects in shoes, like rocks, tacks, or coins, leading to injury, infection, and ulcers.
Dermopathy and other skin conditions
Diabetic dermopathy refers to round, slightly-indented purple/brown patches of skin that most frequently occur on the shins and on skin that has been injured or traumatized. This condition appears to be linked to slow healing.
Fungal infections such as Candida albicans are two and a half times as likely with diabetes.
Necrobiosis lipoidica (NLD) is a disfiguring disease of the legs and feet. Although it is rare in both sexes, women are three times as likely as men to encounter this problem. NLD usually starts as a dull red raised area. Eventually, it will look like a shiny scar with a violet border.
Preventing foot and leg problems in diabetes begins by preventing the loss of circulation that will result in serious nerve damage. This may be achieved through good diabetes management.
Peripheral vascular disease
This disease of the peripheral blood vessels is characterized by narrowing and hardening of the arteries that supply the legs and feet. The narrowing and hardening causes a decrease in blood flow that can injure nerves and other tissues. The narrowing of the arteries may progress to total occlusion of the vessel. Symptoms include leg pain, numbness, cold legs or feet and muscle pain in the thighs, calves or feet.
Coronary artery disease
Damage to the large blood vessels contributes to a decrease in blood circulation. This in turn increases risk of coronary artery disease, ischemic heart disease, stroke, and amputation of the lower limbs. Amputations are 50 percent more common in people with diabetes.
Management/treatment options
Managing diabetes involves the patient, the doctor and all other diabetes care professionals. Achieving optimal treatment goals relies on close interaction and collaboration between all parties. Modes of treatment include:
- Monitoring blood glucose levels
- Medication
- Education
- Diet and nutrition
- Exercise
Type 1 diabetes management involves healthy eating, physical activity, and insulin via injection or an insulin pump. The amount of insulin must be balanced with food intake and daily activities, and blood glucose levels must be closely controlled through frequent monitoring.
Type 2 diabetes management involves healthy eating, physical activity, and blood glucose testing. Many people with Type 2 diabetes require oral medication and insulin to control their blood glucose levels.
The goal of diabetes management is to keep blood glucose levels as close to the normal range as safely possible. A major study, the Diabetes Control and Complications Trial (DCCT), sponsored by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), showed that keeping blood glucose levels as close to normal as safely possible reduces the risk of developing major complications of Type 1 diabetes.
Medications:
Type 1 diabetes
Insulin is used to help manage Type 1 diabetes. Insulin is delivered by injections that are generally required one to four times per day or via an insulin pump that delivers a steady supply of insulin. Since people do not respond to insulin types in the same way, a "trial and error" method is usually required to determine the best treatment protocol.
There are three categories of insulin:
Very fast acting – Fast acting insulins - including lispro (Humalog®) and aspart (Novolog®) - should be injected under the skin within 15 minutes before a meal. These insulins start working in five to 15 minutes and finish working in three to four hours.
Fast acting - Fast acting or regular insulin lowers blood sugar in 2 to 5 hours and finishes its work in 5 to 8 hours.
Intermediate acting - NPH (N) or Lente (L) insulin starts working in 1 to 3 hours, and finishes working in 20 to 24 hours.
The following medication are commonly used to help manage Type 2 diabetes:
Metformin (Glucophage®)
This drug reduces the liver's production and output of sugar. Metformin is contraindicated if the patient suffers from decreased kidney or liver function, heart failure, or occasionally binges on alcohol or has a history of alcoholism.
Pioglitazone (Actos®), Rosiglitazone (Avandia®)
These drugs promote the uptake of sugar into the cells. In females, both drugs may increase the risk of pregnancy if menstrual cycles are irregular. Liver tests should be done before starting a patient on these drugs and should be repeated every two months for the first year. It may take up to six weeks to notice an effect when on piolitazone, and up to eight weeks for rosiglitazone.
Acarbose (Prandase®)
This drug delays the digestion and absorption of sugar from the gut. The blood sugar should be checked two hours after meals.
The following drugs all act on the pancreas to promote insulin secretion:
Glyburide (Diabeta), Gliclazide (Diamicron)
It is important not to miss meals or snacks while taking glyburide or gliclazide. While on these drugs, the patient's sugar readings will be low. There is a possibility of weight gain. Caution should be taken if the patient has an allergy to sulfa pills. Glyburide and gliclazide may cause an increase in sun sensitivity, so the patient should be cautioned to use a good sunscreen.
Glimepiride (Amaryl®)
Glimepiride is contraindicated when kidney, liver or heart disease is present. Caution should be taken if the patient has an allergy to sulfa pills. This drug may cause an increase in sun sensitivity, so the patient should be cautioned to use a good sunscreen.
Repaglinide (Gluconorm®)
It is important to include some carbohydrate with meals when taking this drug. The patient should be cautioned not to skip meals after taking a dose. Caution should be exercised if the patient has poor liver function.
Once again, caution should be exercised if the patient has poor liver function.
Print out Diabetes Risk Factors & Wellness Tips for your patients