What is Diabetes

Diabetes Types
Screening for Diabetes
Diagnosing Diabetes
Targets for Diabetes Treatment

Type 1 Diabetes Mellitus is characterized by destruction of the insulin-secreting cells of the pancreas, leading to an absolute deficiency of insulin. Even though type 1 diabetes can occur at any age, most patients develop it before the age of 30. The most common symptoms are lack of energy, constant hunger, sudden weight loss, frequent urination, excessive thirst, and blurred vision. These symptoms can be sudden in onset. Persons with type 1 diabetes can not survive without injecting insulin into their body. About 5% of persons with diabetes have type 1. Prior to 1997, type 1 diabetes was also known as insulin-dependent diabetes mellitus.

Type 2 Diabetes Mellitus is a term for individuals who have both insulin resistance (a condition in which the cells of the body resist the action of insulin) and insulin deficiency. People with type 2 range from predominantly insulin resistant with decreased insulin secretion to predominantly deficient in insulin secretion with some insulin resistance. Type 2 diabetes is increasing in frequency as people get older, more overweight and less physically active. Recently there has been an alarming increase in type 2 diabetes occurring in children and adolescents, consistent with changes in their lifestyles. The most common symptoms are, again, lack of energy, increased hunger and thirst, frequent urination, blurred vision, loss of feeling in hands and toes, slow healing of infections or wounds, and weight loss. These symptoms are usually gradual in onset. Persons with type 2 diabetes may initially be treated with diet and exercise and then with pills to treat their elevated blood sugar. Subsequently, however, for many insulin is the only effective treatment. About 90% - 95% of persons with diabetes have type 2 diabetes. Prior to 1997, type 2 diabetes was also known as non-insulin-dependent diabetes.

Gestational Diabetes Mellitus (GDM) occurs when a pregnant woman has blood sugar levels that are higher than normal because the body does not make enough insulin or does not use properly the insulin that is made. During normal pregnancy fasting blood sugars range between 60-90 mg/dl, lower than in non pregnant women. Gestational diabetes usually occurs in the last half of pregnancy, affecting up to 5% of all pregnant women. As a result, it is the most common problem of pregnancy today. After the baby is born, the mother's blood sugar levels usually return to normal. Type 2 diabetes can develop later in life in majority of women who have had gestational diabetes and who are overweight. The baby may also develop diabetes as an adult, and girls may be prone to developing gestational diabetes.

Prediabetes This term was coined in 2001 to signify both the condition that precedes onset of frank type 2 diabetes and also the fact that onset of diabetes can be prevented at this stage (by calorie-restricted diet and increased physical activity). It is defined as that disease in which individuals have either "impaired fasting glucose" (i.e. plasma glucose between 100 and 125 mg/dl) or "impaired glucose tolerance" (i.e. plasma glucose between 140 and 199 mg/dl two hours after the 75-gram glucose-containing drink is ingested during oral glucose tolerance test).

^ Up to Top

Screening For Diabetes

Testing for diabetes should be done at age 45. If normal, repeat every 3 years.
Testing should be done at a younger age, and more frequently in persons 45 and older, who:

• are obese (>120% desirable body weight or a body mass index (BMI) >27 kg/m²)
• have a first-degree relative with diabetes
• are a member of a high-risk ethnic population (African American, Hispanic, Native American, Asian)
• delivered a baby weighing over 9 lb. or were diagnosed with Gestational Diabetes Mellitus
• are hypertensive (blood pressure >140/80)
• have an HDL cholesterol level < 50 mg/dl
• on previous testing, had Impaired Glucose Tolerance or Impaired Fasting Glucose

^ Up to Top

Diagnosing Diabetes

There are 4 ways diabetes can be diagnosed:

• After at least 8 hours of not eating or drinking anything, blood is drawn and the Fasting Plasma Glucose is measured. A result of >126 mg/dl is indicative of diabetes. This is the preferred diagnostic test because of its ease of administration, convenience, and lower cost.
• Before diagnosis of diabetes can be confirmed, the result (fasting plasma glucose > 126 mg/dl) needs to be repeated on a different day. Random (sometimes called "casual") Plasma Glucose can also be done to diagnose diabetes. This test can be done at anytime without regard to the time of the last meal. A result higher than 200 mg/dl with classic symptoms (increased hunger, excessive thirst, and weight loss) denotes diabetes. If there are no symptoms the blood test has to be done on a different day.
• Oral Glucose Tolerance Test, involves drinking glucose dissolved in water and then having blood drawn two hours later. A result of >200 mg/dl signifies diabetes. To confirm the diagnosis, the test should be repeated on another day.
• Glycated hemoglobin (hemoglobin A1c, A1c) was adopted by the Amertican Diabetes Association as another way to diagnose diabetes. Level of 6.5% and above signifies diagnosis of diabetes. This test has not been accepted by other organizations yet as a reliable diagnostic criterion.

Diagnostic criteria are not treatment goals.

^ Up to Top

Targets for Diabetes Treatment

For patients checking their blood glucose levels, the American Diabetes Association guidelines call for preprandial (before meals) capillary plasma glucose 70–130 mg/dl (5.0–7.2 mmol/l), peak postprandial (after meals) capillary plasma glucose under 180 mg/dl and 100 -140 mg/dl at bedtime.

The long-term control is assessed by a test called hemoglobin A1c (HgbA1c). An A1c score of 5.7 to 6.4 percent indicates prediabetes and an A1c level of 6.5 percent or higher is diagnostic of diabetes. The American Diabetes Association recommends that most people with diabetes maintain a goal of keeping A1C levels at or below 7 percent in order to properly manage their disease.

The American College of Endocrinology suggests A1c at or below 6.5%, premeal glucose under 110 mg/dl and 2-hour after meal glucose of under 140 mg/dl.