A new tool for screening diabetics may not require patients to undertake fasting, researchers at Johns Hopkins School of Medicine in Baltimore have suggested.
They examined the current criteria for screening and diagnosing the disease and found a significant need for improvement.
"There are serious deficiencies in the current criteria for diagnosing diabetes and these shortcomings are contributing to avoidable morbidity and mortality," Christopher Saudek, M.D., of Johns Hopkins School of Medicine in Baltimore, Md., and lead author of the report, said.
Saudek said that one reason why many people with diabetes remain undiagnosed is because commonly prescribed diagnostic tests require that a patient be fasting, which means that people who have eaten on the day of a doctor visit will not be diagnosed unless they have quite advanced diabetes.
As a substitute for the fasting plasma glucose or oral glucose tolerance tests, the researchers have suggested incorporating another measurement of glucose - hemoglobin A1c (HbA1c) - into criteria for screening and diagnosing diabetes.
Hemoglobin is the oxygen-carrying protein located in red blood cells. HbA1c is a form of hemoglobin that reflects the average blood glucose level over the previous several months, and has been used for a long time to indicate blood sugar levels in patients with diabetes.
However, it has never been officially accepted as a way for doctors to screen for or diagnose diabetes.
Present recommendations of the American Diabetes Association were made 10 years ago and they rejected the use of HbA1c as a diagnostic tool largely because it was considered at the time to be inadequately standardized and insensitive.
Given more recent evidence, the panel believes that it is time to revisit using HbA1c and include it as necessary criteria in screening and diagnosing diabetes.
The measurement of HbA1c does not require fasting, while current accepted tests require the patient to fast for at least eight hours.
In addition, HbA1c more accurately reflects longer-term glucose concentration in the blood; other tests can easily be affected by short-term lifestyle changes, such as a few days of dieting or exercise.
Besides this, HbA1c laboratory methods are now well standardized and reliable.
The panel suggested that screening standards be established that prompt further testing and closer follow-up.
The study is published in the Journal of Clinical Endocrinology and Metabolism (JCEM).