"More diabetes patients are taking medication to control their blood pressure and cholesterol, but too few are making needed lifestyle changes such as exercising, lowering dietary fat, and losing weight to control the risk factors for diabetes complications," noted author Dr. Catherine Cowie of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), one of the National Institutes of Health.
The researchers compared data obtained from a nationally representative sample of U.S. adults age 20 years and older with diagnosed diabetes who took part in either the Third National Health and Nutrition Examination Survey (NHANES III) conducted from 1988 to 1994 or the NHANES conducted from 1999 to 2000.
Participants in the later survey, though similar in age and gender, were heavier, diagnosed with diabetes younger, and more likely to be using insulin along with oral drugs to treat their diabetes. Only 37 percent (compared to 44 percent in the earlier NHANES) were achieving the American Diabetes Association's (ADA) goal for blood glucose control--a hemoglobin A1c (HbA1c) blood test result of less than 7 percent. About 37 percent of participants in the later survey had HbA1c levels above 8 percent, ADA's recommended "take action" level.
Although the percentage of people with diagnosed diabetes taking blood pressure medication has risen in the last decade, only 36 percent of participants in the most recent NHANES met ADA's current blood pressure goal of less than 130/80 mmHg, and 40 percent had high blood pressure. More participants in the later survey were also receiving medication to lower high cholesterol, but 52 percent still had total cholesterol levels above 200 mg/dl.
The NHANES surveys did not ask participants which type of diabetes they had. According to the recently updated National Diabetes Statistics Fact Sheet, 18.2 million people--6.3 percent of the population--have diabetes. Type 2 diabetes accounts for up to 95 percent of all diabetes cases. Most common in adults over age 40, this form of diabetes is strongly linked to obesity, inactivity, family history of diabetes, and racial or ethnic background.
Diabetes is the main cause of kidney failure, limb amputations, and new onset blindness in adults and is a major cause of heart disease and stroke. Many clinical trials have proven that these complications can be dramatically reduced with good control of blood glucose, blood pressure and cholesterol. National campaigns such as the National Diabetes Education Program's "Be Smart about your Heart. Control the ABCs of Diabetes" (HbA1c, Blood Pressure, and Cholesterol) (www.ndep.nih.gov/) have led to a wider awareness of the need to control the risk factors for diabetes complications. But more needs to be done, the study's authors conclude.
"We must redouble our efforts to empower patients and providers with information and tools to improve therapy and to provide incentives for the comprehensive care that has been proven effective in reducing diabetes complications," said coauthor Dr. Judith Fradkin, director of NIDDK's Diabetes, Endocrinology, and Metabolic Diseases Division.
The study was conducted by Drs. Fradkin and Cowie of the NIDDK and Dr. Sharon Saydah of Social and Scientific Systems, Inc. The work was funded by NIDDK, one of the National Institutes of Health under the U.S. Department of Health and Human Services.