There are two major types of diabetes.
- TYPE 1 Juvenile diabetes or insulin-dependent diabetes mellitus (IDDM) is an autoimmune related disease, usually striking between the ages of 5 and 20 years, in which patients have lost all insulin production.
- TYPE 2 Adult onset or non-insulin dependent diabetes mellitus (NIDDM) represents 90 to 95% of all diabetes, and is caused by a combination of insulin resistance and a relative insulin deficiency. Physical health is key to this syndrome as 80% of sufferers are overweight and physically inactive. This was once thought to be a middle aged disease, but since childhood obesity has been on the rise, cases of Type 2 diabetes are being diagnosed at every age. The majority of Type 2 diabetics are still over 55. A newer classification, Type 1.5, is discussed below.
Early diagnosis is important for this, a disease that is spiraling out of control. Lifestyle options which include weight loss, rigid restrictions of grains, sugars and root vegetables along with one hour of daily aerobic activity seems to control Type 2 diabetes in a majority of people unless they have serious damage in their pancreas or insulin receptors.
Type 1.5 Diabetes
Type 1.5 is one of several names now applied to those who are diagnosed with diabetes as adults, but who do not immediately require insulin for treatment, are often not overweight, and have little or no resistance to insulin. When special lab tests are done, they are found to have antibodies, especially GAD65 antibodies (glutamic acid decarboxylase), that attack their beta cells. This sort of diabetes is sometimes called Slow Onset Type 1 or Latent Autoimmune Diabetes in Adults (LADA). About 15% to 20% of people diagnosed as Type 2 actually have this type. They are often diagnosed as Type 2 because they are older and will initially respond to diabetes medications because they have adequate insulin production. The treatment the person is first put on may be diet, exercise, and standard Type 2 medications.
Since insulin resistance is minimal or nonexistent, medications designed to reduce insulin resistance such as Avandia and Actos are not effective. Other medications that stimulate the pancreas to produce insulin, slow digestion of carbohydrates, or reduce excess glucose production by the liver are often effective in controlling the blood sugar for a few years.
One study done in Bruneck, Italy found that 84% of the people diagnosed as Type 2 had insulin resistance, but the other 16% did not, suggesting these individuals had Type 1.5. Several other studies have shown similar results, and these studies also often show the presence of antibodies characteristic of Type 1 in this group of people diagnosed with Type 2.
A misdiagnosis is easy to make when the person is older and responds well at first to treatment with oral medications. If someone does not clearly fit the model for Type 1, they may be mistakenly placed on oral agents even though limited capacity for insulin production remains. The immune system’s slower and more selective attack on the beta cells allows these cells to function to a high degree for a few years. On average, insulin is required in half of those with Type 1.5 diabetes within four years of diagnosis, compared to over ten years in those with true Type 2.
Knowing your diabetes type can give you a better understanding of the changes that may occur to you as you age and your disease progresses. For example, if you have had insulin resistant diabetes for several years that has become harder to control on a sulfonylurea medication and your C peptide level, a lab test that measures insulin production, is now low, the addition of insulin will be needed. But if your control is poor and your C peptide is normal, adding another oral agent and paying closer attention to your food and exercise choices may be all that’s needed.
In the late 1990’s, Dr. David Bell, a clinician and researcher in Birmingham, Alabama, wanted to see if he could eliminate insulin use in a group of people with Type 2 diabetes who were already on insulin by using a combination of oral medications. These people often had been put on insulin without first trying oral medications because today’s array of medications were not available when they were diagnosed.
Dr. Bell first tested C peptide levels and chose only those who had normal levels. Of the 130 people with adequate C peptide levels in his study, 100 were able to discontinue insulin use altogether and control their diabetes on various doses of glyburide and metformin. He found that their overall control, measured by their HbA1c levels, was actually better on two oral medications than it had been previously on two daily doses of insulin. Others in the study were able to improve their hemoglobin levels by using glyburide and metformin with a single dose of insulin at dinner or bedtime.
Researchers have determined that the Type 2 patients most likely to control their blood sugars on combination oral agents are those least overweight (BMI of 30 or less), with shortest duration of diabetes, and C peptide levels normal or only slightly low.
As insulin production falls, insulin becomes necessary to maintain control. One clue that people have Type 1.5 rather than Type 2 is their appearance, which is more likely though not always slender and physically fit. They often do not have other signs of Type 2 diabetes, such as the Syndrome X cluster of high TGs, low HDL or high blood pressure. Luckily, in these early stages, diabetes treatment is not significantly different for slow onset Type 1.5s compared to truly insulin resistant Type 2s. The only exception is that drugs designed to increase insulin sensitivity like the glitazones do not work because insulin sensitivity is normal.
One major benefit to this type is that when their blood sugars are controlled, people with Type 1.5 usually do not have the high risk for heart problems more often found with the high cholesterol and blood pressure seen in true Type 2 diabetes.
Type 2 diabetes is a gradual syndrome with the signs of diabetes developing over several years. Although a person may experience excessive urination and thirst, there may be no other apparent diabetic signs. Weight loss and hunger may go unnoticed. For this reason, annual screening for the disease after age 45 is a good idea, especially for anyone who is in a high risk category.
Type 2 Diabetes
Although the pancreatic beta cells of patients with NIDDM usually continue to produce insulin, for some reason the body does not respond to the insulin effectively. Beta cells are the cells of the pancreas that regulate glucose levels in the body by producing insulin. The first step towards type 2 diabetes is insulin resistance, a condition in which the key target tissues for insulin (muscle and fat) do not respond normally to that hormone. Both genetic traits and acquired factors (such as aging, diet and obesity) play a role in the development of insulin resistance. Beta cells compensate for insulin resistance with increased insulin secretion resulting in hyperinsulinemia. In this compensated, insulin resistant state known as impaired glucose tolerance (IGT), blood glucose remains normal throughout most of the day, but may become high after meals.
IGT (insulin resistance) is very common in Western society, afflicting an estimated 20 million individuals in the United States alone. Over time, beta cells are unable to continue to secrete the high levels of insulin needed to maintain normal glucose levels in the face of chronic ingestion of simple sugars and refined carbohydrates. When this occurs, the patient develops elevated blood glucose throughout the day, indicative of type 2 diabetes. Insulin resistance is also found in a variety of other common disease states including hypertension, atherosclerosis, obesity and polycystic ovarian syndrome. In some of these conditions insulin resistance has been shown to be an independent risk factor contributing to the disease and its complications. Progression to type 2 diabetes occurs in approximately 7% of patients with IGT every year. The end result is the same as for insulin dependent diabetes (IDDM) which is an unhealthy buildup of glucose in the blood and an inability of the body to make efficient use of its main source of fuel.
The symptoms of NIDDM develop gradually and are not as noticeable as in IDDM. Symptoms include feeling tired or ill, frequent urination (especially at night), unusual thirst, weight loss, blurred vision, frequent infections, and slow wound healing. Excessively low glucose from too much injected insulin or too little food can cause the affected individual to lose consciousness, experience seizures or even die.
Chronic complications typically take five to ten years to manifest themselves, are generally irreversible and are predominantly caused by sustained high levels of blood glucose. Diabetes is widely recognized as one of the leading causes of death and disability in the United States, and it is associated with long term complications that affect almost every major part of the body. It can lead to blindness, heart disease, strokes, kidney failure, amputations, and nerve damage. Uncontrolled diabetes can complicate pregnancy, and birth defects are more common in babies born to women with diabetes. Due to these complications, the life expectancy of a diabetic is 30 to 50% less than a nondiabetic person from the time he or she is diagnosed. People diagnosed with adult onset diabetes before the age of 40 could expect to die eight years earlier than healthy contemporaries.
October, 2008 – New figures released by the Centers for Disease Control and Prevention (CDC) have revealed that the incidence of type 2 diabetes in the US has risen by 90% within just ten years. This is based upon self-reporting, so the incidence should be considered higher as some who have diabetes do not yet know it.