On June 23, 1997, an international Expert Committee recommended lowering the number for diagnosis on the most commonly used test for diabetes and urged that consideration be given to wide-scale screening and testing in order to detect diabetes at an earlier stage and help prevent or delay the onset of serious and costly complications.
Simplified Testing and Diagnosis
The committee
recommends the health care community consider testing for diabetes in all
adults at age 45 and above, and if normal, repeat testing at three-year
intervals. Testing should be considered at a younger age, or be carried out
more frequently, in individuals at high risk for diabetes.
Diabetes can be diagnosed by one of the following three ways,
confirmed on a different day: (1) a fasting plasma glucose (FPG) of
126 mg/dl (after no caloric intake for at least 8 hours)
(preferred test); (2) a casual plasma glucose (taken at any time of day without
regard to time of last meal)
200 mg/dl with the classic diabetes symptoms of
increased urination, increased thirst, and unexplained weight loss; or (3) an
oral glucose tolerance test (OGTT) value of
200 mg/dl in the two-hour sample.
The hemoglobin A1c test (also known at HbA1c or glycosylated hemoglobin) is not recommended for diagnosis. The finger-prick test used by people with diabetes to monitor their blood glucose levels, and sometimes used for screening at health fairs, is not considered a diagnostic procedure.
110 but < 126 mg/dl; 140 by < 200 mg/dl (in the two-hour sample). Who Should be Tested and When
The committee
recommends that testing for diabetes should be considered in all adults at age
45 and above, and if normal, be repeated at three year intervals. Physicians
should consider testing at a younger age, or more frequently, those who are
higher risk of diabetes, including people who:
Name Changes
To clarify what is being
diagnosed, the Committee recommended eliminating the old categories of
"insulin-dependent diabetes mellitus" (IDDM) and
"non-insulin-dependent diabetes mellitus" (NIDDM) because they are
based on treatment which can vary considerably and does not indicate the
underlying problem. Further, in discussing the types of diabetes, the use of
Arabic (type 1 and type 2) rather than Roman (type I and type II) numerals is
recommended to prevent confusion (e.g., type II being read as "type
eleven").
Approximately 700,000 Americans have type 1 diabetes, a disease characterized by destruction of the pancreatic beta cells which produce insulin, usually leading to absolute insulin deficiency. It has two forms. Immune-Mediated Diabetes Mellitus results from an autoimmune destruction of the beta cells; it typically starts in children or young adults who are slim, but can arise in adults of any age. Idiopathic type 1 refers to rare forms of the disease that have no known cause.
Type 2 diabetes usually arises because of insulin resistance, in which the body fails to use insulin properly, combined with relative (rather than absolute) insulin deficiency. People with type 2 can range from predominantly insulin resistant with relative insulin deficiency to predominantly deficient in insulin secretion with some insulin resistance. It typically occurs in those over 45, overweight and sedentary, with a family history of diabetes. Approximately 15.3 million Americans have type 2 diabetes.
Several other specific types of DM have been defined, such as those resulting from genetic defects of B-cell function, pancreatic diseases (i.e. cystic fibrosis), and defects in insulin action. Maturity-onset diabetes of the young is associated with monogenetic defects in B-cell function that are characterized by impaired insulin secretion with minimal or no defects in insulin action. The disease is inherited as in an autosomal dominant pattern and the onset of hyperglycemia occurs at an early age (generally before age 25 years).
Special Recommendations for Pregnant Women
While the category of gestational diabetes (which complicates
about four percent of U.S. pregnancies) is retained, the recommendation for
screening of all pregnant women has been dropped. The
Committee now recommends that women at low risk not be screened. This includes
women who satisfy all of the following criteria: less than 25 years of age,
normal body weight, have no family history of diabetes, and
are not a member of an ethnic group with a high prevalence of diabetes.
Report of the Expert Committee on the diagnosis and classification of diabetes mellitus: American Diabetes Association: Clinical practice recommendations 1998, Diabetes Care 21 (suppl 1):S5-S19, 1998. www.diabetes.org/ada/nwclass.htm.
See Chapter 29 in Essentials of Pediatric Nursing, 5th edition.
See Chapter 38 in Nursing Care of Infants and Children, 5th and 6th editions.
March 15, 2002