What is Diabetes?
Diabetes mellitus is a group of metabolic diseases characterized by high blood sugar (glucose) levels, that result from defects in insulin secretion, or action, or both. Diabetes mellitus, commonly referred to as diabetes (as it will be in this article) was first identified as a disease associated with "sweet urine," and excessive muscle loss in the ancient world. Elevated levels of blood glucose (hyperglycemia) lead to spillage of glucose into the urine, hence the term sweet urine.
Normally, blood glucose levels are tightly controlled by insulin, a hormone produced by the pancreas. Insulin lowers the blood glucose level. When the blood glucose elevates (for example, after eating food), insulin is released from the pancreas to normalize the glucose level. In patients with diabetes, the absence or insufficient production of insulin causes hyperglycemia. Diabetes is a chronic medical condition, meaning that although it can be controlled, it lasts a lifetime.
What is the impact of diabetes?
Over time, diabetes can lead to blindness, kidney failure, and nerve damage. These types of damage are the result of damage to small vessels, referred to as microvascular disease. Diabetes is also an important factor in accelerating the hardening and narrowing of the arteries (atherosclerosis), leading to strokes,coronary heart disease, and other large blood vessel diseases. This is referred to as macrovascular disease. Diabetes affects approximately 17 million people (about 8% of the population) in the United States. In addition, an estimated additional 12 million people in the United States have diabetes and don't even know it.
From an economic perspective, the total annual cost of diabetes in 1997 was estimated to be 98 billion dollars in the United States. The per capita cost resulting from diabetes in 1997 amounted to $10,071.00; while healthcare costs for people without diabetes incurred a per capita cost of $2,699.00. During this same year, 13.9 million days of hospital stay were attributed to diabetes, while 30.3 million physician office visits were diabetes related. Remember, these numbers reflect only the population in the United States. Globally, the statistics are staggering.
Diabetes is the third leading cause of death in the United States after heart disease and cancer.
TYPES OF DIEBETES MELLITUS!
Diabetes mellitus type 1 (Type 1 diabetes, T1D, T1DM, IDDM, juvenile diabetes) is a form of diabetes mellitus. Type 1 diabetes is an autoimmune disease that results in destruction of insulin-producing beta cells of the pancreas. Lack of insulin causes an increase of fasting blood glucose (around 70-120 mg/dL in nondiabetic people) that begins to appear in the urine above the renal threshold (about 190-200 mg/dl in most people), thus connecting to the symptom by which the disease was identified in antiquity, sweet urine. Glycosuria or glucose in the urine causes the patients to urinate more frequently, and drink more than normal (polydipsia). Classically, these were the characteristic symptoms which prompted discovery of the disease.
Type 1 is lethal unless treated with exogenous insulin. Injection is the traditional and still most common method for administering insulin; jet injection, indwelling catheters, and inhaled insulin has also been available at various times, and there are several experimental methods as well. All replace the missing hormone formerly produced by the now non-functional beta cells in the pancreas. In recent years, pancreas transplants have also been used to treat type 1 diabetes. Islet cell transplant is also being investigated and has been achieved in mice and rats, and in experimental trials in humans as well.Use of stem cells to produce a new population of functioning beta cells seems to be a future possibility, but has yet to be demonstrated even in laboratories as of 2008.
Type 1 diabetes (formerly known as "childhood", "juvenile" or "insulin-dependent" diabetes) is not exclusively a childhood problem; the adult incidence of type 1 is noteworthy—many adults who contract type 1 diabetes are misdiagnosed with type 2 due to confusion on this point.
There is currently no clinically useful preventive measure against developing type 1 diabetes, though a vaccine has been proposed and anti-antibody approaches are also being tested. Most people who develop type 1 were otherwise healthy and of a healthy weight on onset, but they can lose weight quickly and dangerously, if not promptly diagnosed. Although the cause of type 1 diabetes is still not fully understood, the immune system damage is characteristic of type 1.
The most definite laboratory test to distinguish type 1 from type 2 diabetes is the C-peptide assay, which is a measure of endogenous insulin production since external insulin has not (to date) included C-peptide. The presence of anti-islet antibodies (to Glutamic Acid Decarboxylase, Insulinoma Associated Peptide-2 or insulin), or lack of insulin resistance, determined by a glucose tolerance test, would also be suggestive of type 1. Many type 2 diabetics continue to produce insulin internally, and all have some degree of insulin resistance.
Testing for GAD 65 antibodies has been proposed as an improved test for differentiating between type 1 and type 2 diabetes as it appears that the immune system malfunction is connected with their presence. Further, injections with GAD65 has in clinical trials delayed the destruction of beta cells for at least 30 months, without serious adverse effects. Patients treated with the substance showed higher levels of regulatory cytokines, thought to protect the beta cells. Phase III trials are under way in the USA and in Europe, with most sites actively pursuing participants.
Diabetes mellitus type 2 or type 2 diabetes (formerly called non-insulin-dependent diabetes mellitus (NIDDM), or adult-onset diabetes) is a disorder that is characterized by high blood glucose in the context of insulin resistance and relative insulin deficiency.While it is often initially managed by increasing exercise and dietary modification, medications are typically needed as the disease progresses. There are an estimated 23.6 million people in the U.S. (7.8% of the population) with diabetes with 17.9 million being diagnosed, 90% of whom are type 2. With prevalence rates doubling between 1990 and 2005, CDC has characterized the increase as an epidemic.
Traditionally considered a disease of adults, type 2 diabetes is increasingly diagnosed in children in parallel to rising obesity rates due to alterations in dietary patterns as well as in life styles during childhood.
Unlike type 1 diabetes, there is little tendency toward ketoacidosis in type 2 diabetes, though it is not unknown. One effect that can occur is nonketonic hyperglycemia which also is quite dangerous, though it must be treated very differently. Complex and multifactorial metabolic changes very often lead to damage and function impairment of many organs, most importantly the cardiovascular system in both types. This leads to substantially increased morbidity and mortality in both type 1 and type 2 patients, but the two have quite different origins and treatments despite the similarity in complications.
Special regards by
Dr.M M ADNAN