Diabetes mellitus, often referred to simply as diabetes, is a disease in which the body does not produce or properly use insulin. Insulin is a hormone that is needed to convert sugar, starches and other food into energy needed for daily life. The cause of diabetes continues to be a mystery, although both genetics and environmental factors such as obesity and lack of exercise appear to play roles.
In order to determine whether or not a patient has pre-diabetes or diabetes, health care providers conduct a Fasting Plasma Glucose Test (FPG) or an Oral Glucose Tolerance Test (OGTT). Either test can be used to diagnose pre-diabetes or diabetes.
With the FPG test, a fasting blood glucose level between 100 and 125 mg/dl signals pre-diabetes. A person with a fasting blood glucose level of 126 mg/dl or higher has diabetes.
In the OGTT test, a person's blood glucose level is measured after a fast and two hours after drinking a glucose-rich beverage. If the two-hour blood glucose level is between 140 and 199 mg/dl, the person tested has pre-diabetes. If the two-hour blood glucose level is at 200 mg/dl or higher, the person tested has diabetes.
MAJOR TYPES
· Type 1 diabetes: results from the body's failure to produce insulin, the hormone that "unlocks" the cells of the body, allowing glucose to enter and fuel them. It is estimated that 5-10% of Americans who are diagnosed with diabetes have type 1 diabetes.
· Type 2 diabetes: results from insulin resistance (a condition in which the body fails to properly use insulin), combined with relative insulin deficiency. Most Americans who are diagnosed with diabetes have type 2 diabetes.
· Gestational diabetes: immediately after pregnancy, 5% to 10% of women with gestational diabetes are found to have diabetes, usually, type 2.
· Pre-diabetes: 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. There are 57 million Americans who have pre-diabetes, in addition to the 23.6 million with diabetes.
SYMPTOMS
The classical symptoms are polyuria and polydipsia which are, respectively, frequent urination and increased thirst and consequent increased fluid intake. Symptoms may develop quite rapidly (weeks or months) in type 1 diabetes, particularly in children.
However, in type 2 diabetes symptoms usually develop much more slowly and may be subtle or completely absent. Type 1 diabetes may also cause a rapid yet significant weight loss (despite normal or even increased eating) and irreducible mental fatigue. All of these symptoms except weight loss can also manifest in type 2 diabetes in patients whose diabetes is poorly controlled, although unexplained weight loss may be experienced at the onset of the disease. Final diagnosis is made by measuring the blood glucose concentration.
When the glucose concentration in the blood is raised beyond its renal threshold, reabsorption of glucose in the proximal renal tubuli is incomplete, and part of the glucose remains in the urine (glycosuria). This increases the osmotic pressure of the urine and inhibits reabsorption of water by the kidney, resulting in increased urine production (polyuria) and increased fluid loss. Lost blood volume will be replaced osmotically from water held in body cells and other body compartments, causing dehydration and increased thirst.
Prolonged high blood glucose causes glucose absorption, which leads to changes in the shape of the lenses of the eyes, resulting in vision changes; sustained sensible glucose control usually returns the lens to its original shape. Blurred vision is a common complaint leading to a diabetes diagnosis; type 1 should always be suspected in cases of rapid vision change, whereas with type 2 change is generally more gradual, but should still be suspected.
Patients (usually with type 1 diabetes) may also initially present with diabetic ketoacidosis (DKA), an extreme state of metabolic dysregulation characterized by the smell of acetone on the patient's breath; a rapid, deep breathing known as Kussmaul breathing; polyuria; nausea; vomiting and abdominal pain; and any of many altered states of consciousness or arousal (such as hostility and mania or, equally, confusion and lethargy). In severe DKA, coma may follow, progressing to death. Diabetic ketoacidosis is a medical emergency and requires immediate hospitalization.
A rarer but equally severe possibility is hyperosmolar nonketotic state, which is more common in type 2 diabetes and is mainly the result of dehydration due to loss of body water. Often, the patient has been drinking extreme amounts of sugar-containing drinks, leading to a vicious circle in regard to the water loss.
TREATMENT
Diabetes is currently a chronic disease with no cure. Medical emphasis must necessarily be on managing or avoiding possible short-term as well as long-term diabetes-related problems. There is an exceptionally important role for patient education, dietetic support, sensible exercise, self monitoring of blood glucose, with the goal of keeping both short-term and long-term blood glucose levels within acceptable bounds.
Careful control is needed to reduce the risk of long term complications. This is theoretically achievable with combinations of diet, exercise and weight loss (type 2), various oral diabetic drugs (type 2 only), and insulin use (type 1 and for type 2 not responding to oral medications, mostly those with extended duration diabetes).
Many type 1 treatments include combination use of regular or NPH insulin, and/or synthetic insulin analogs (e.g., Humalog, Novolog or Apidra) in combinations such as Lantus/Levemir and Humalog, Novolog or Apidra. Another type 1 treatment option is the use of the insulin pump (e.g., from Deltec Cozmo, Animas, Medtronic Minimed, Insulet Omnipod, or ACCU-CHEK). A blood lancet is used to pierce the skin (typically of a finger), in order to draw blood to test it for sugar levels.
Oral administration of aloe vera might be a useful adjunct for lowering blood glucose in diabetic patients as well as for reducing blood lipid levels in patients with hyperlipidaemia. Ten controlled clinical trials were found to reach that conclusion in four independent literature searches. However, caveats reported in each study led the researchers to conclude that aloe vera's clinical effectiveness was not yet sufficiently defined in 1999.
PREVENTION
Maintaining an ideal body weight and an active lifestyle may prevent type 2 diabetes. Currently there is no way to prevent type 1 diabetes. There is no effective screening test for type 1 diabetes in people who don't have symptoms.
Screening for type 2 diabetes and people with no symptoms is recommended for:
· Overweight children who have other risk factors for diabetes starting at age 10 and repeating every 2 years
· Overweight adults (BMI greater than 25) who have other risk factors
· Adults over 45, repeated every 3 years
To prevent complications of diabetes, visit your health care provider or diabetes educator at least four times a year. Talk about any problems you are having.
Regularly have the following tests:
· Have your blood pressure checked every year (blood pressure goals should be 130/80 mm/Hg or lower).
· Have your glycosylated hemoglobin (HbA1c) checked every 6 months if your diabetes is well controlled, otherwise every 3 months.
· Have your cholesterol and triglyceride levels checked yearly (aim for LDL levels below 100 mg/dL).
· Get yearly tests to make sure your kidneys are working well (microalbuminuria and serum creatinine).
· Visit your ophthalmologist (preferably one who specializes in diabetic retinopathy) at least once a year, or more often if you have signs of diabetic retinopathy.
· See the dentist every 6 months for a thorough dental cleaning and exam. Make sure your dentist and hygienist know that you have diabetes.
· Make sure your health care provider inspects your feet at each visit.
· Stay up-to-date with all of your vaccinations and get a flu shot every year in the fall.
