New Survey Results Show Huge Burden of Diabetes
01/26/2009
http://www.nih.gov/news/health/jan2009/niddk-26.htm
For Immediate
Release Monday, January 26, 2009 |
Study Includes Sensitive Test of Blood Glucose Abnormalities
In the United States, nearly 13 percent of adults age 20 and older have diabetes, but 40 percent of them have not been diagnosed, according to epidemiologists from the National Institutes of Health (NIH) and the Centers for Disease Control and Prevention (CDC), whose study includes newly available data from an Oral Glucose Tolerance Test (OGTT). Diabetes is especially common in the elderly: nearly one-third of those age 65 and older have the disease. An additional 30 percent of adults have pre-diabetes, a condition marked by elevated blood sugar that is not yet in the diabetic range. The researchers report these findings in the February 2009 issue of Diabetes Care, which posted a pre-print version of the article online at http://diabetes.org/diabetescare.
The study compared the results of two national surveys that included a fasting blood glucose (FBG) test and 2-hour glucose reading from an OGTT. The OGTT gives more information about blood glucose abnormalities than the FBG test, which measures blood glucose after an overnight fast. The FBG test is easier and less costly than the OGTT, but the 2-hour test is more sensitive in identifying diabetes and pre-diabetes, especially in older people. Two-hour glucose readings that are high but not yet diabetic indicate a greater risk of cardiovascular disease and of developing diabetes than a high, but not yet diabetic, fasting glucose level.
âWeâre facing a diabetes epidemic that shows no signs of abating, judging from the number of individuals with pre-diabetes,â said lead author Catherine Cowie, Ph.D., of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), a part of the NIH. âFor years, diabetes prevalence estimates have been based mainly on data that included a fasting glucose test but not an OGTT. The 2005-2006 National Health and Nutrition Examination Survey, or NHANES, is the first national survey in 15 years to include the OGTT. The addition of the OGTT gives us greater confidence that weâre seeing the true burden of diabetes and pre-diabetes in a representative sample of the U.S. population.â
Diabetes is a group of diseases marked by high levels of blood glucose resulting from defects in insulin production, insulin action, or both. It is the most common cause of blindness, kidney failure, and amputations in adults and a leading cause of heart disease and stroke. Type 2 diabetes accounts for up to 95 percent of all diabetes cases and virtually all cases of undiagnosed diabetes. Pre-diabetes, which causes no symptoms, substantially raises the risk of a heart attack or stroke and of developing type 2 diabetes.
In its analysis, the team also found that:
- The rate of diagnosed diabetes increased between the surveys, but the prevalence of undiagnosed diabetes and pre-diabetes remained relatively stable.
- Minority groups continue to bear a disproportionate burden. The prevalence of diabetes, both diagnosed and undiagnosed, in non-Hispanic blacks and Mexican- Americans is about 70 to 80 percent higher than that of non-Hispanic whites.
- Diabetes prevalence was virtually the same in men and women, as was the proportion of undiagnosed cases.
- Pre-diabetes is more common in men than in women (36 percent compared to 23 percent).
- Diabetes is rare in youth ages 12 to 19 years, but about 16 percent have pre-diabetes.