New Medical Definitions Label
75 Percent of Americans 'Diseased'
NEW YORK - Various medical organizations are calling for the diagnostic definitions of four major illnesses - diabetes, high blood pressure, high cholesterol, and overweight - to be changed in order to encourage early detection and treatment. However, researchers warn that under these new standards, 75 percent of the U.S. adult population would be considered diseased.
And whether these "new 'patients' would ultimately benefit from early detection and treatment of these conditions is unknown," write Drs. Lisa Schwartz and Steven Woloshin of the Dartmouth Medical School in Hanover, New Hampshire. Their analysis is published in the April issue of the journal Effective Clinical Practice.
The authors examined data from the Third National Health and Nutrition Examination Survey, a nationwide health survey conducted between 1988-1994 by the US Centers for Disease Control and Prevention in Atlanta, Georgia. They used survey data to estimate the impact of proposed new definitions of four major chronic health conditions: diabetes, hypertension, high blood cholesterol, and overweight.
For example, the Expert Committee on the Diagnosis and Classification of Diabetes Mellitus recently advocated that the threshold for diabetes be lowered from a fasting glucose of 140 mg/dL to 126 mg/dL. Based on the CDC survey data, the Dartmouth authors estimate that such a change would increase the number of American diabetics by over 1.7 million.
Likewise, changes proposed by the Joint National Committee on Detection, Evaluation and Treatment of High Blood Pressure would lower the definition of high blood pressure from 160/100 mm Hg to 140/90 mm Hg. This new diagnostic threshold would increase the number of US hypertensives by 13 million patients, according to the researchers.
Similar changes advocated by other organizations would add 42 million Americans to the ranks of patients with high blood cholesterol, and 29 million Americans to the list of the overweight.
Altogether, according to the Dartmouth team, broadening diagnostic standards would "ultimately label 75% of the adult US population as diseased."
While the new definitions may help physicians diagnose some cases of disease earlier, they may also increase levels of public anxiety. "In a nation already obsessed with weight and body image and in which eating disorders are prevalent, labeling half the population 'overweight,' for example, may be traumatic," the authors point out.
In his editorial commentary, Dr. H. Gilbert Welch points out that a widening of disease definitions may lead to a situation where "people who previously felt healthy... are being unnecessarily informed that they are sick."
Many patients in these stages of so-called 'early disease' may not even respond to therapy, and "some will be treated unnecessarily," Welch explained.
He also believes that in their zeal for early detection, physicians may unnecessarily alarm the public (Welch cites the '1-in-9' risk for breast cancer, for example). He also asks "if the focus on finding early disease is distracting us from caring for the sick."
The current HMO culture, with its emphasis on prevention rather than treatment, may encourage this trend, Welch explained. "It is clearly easier for health plans to measure how well providers comply with screening recommendations than it is to determine how good they are at helping sick patients," he writes.
Welch and the Dartmouth researchers agree that the prevention of major chronic illnesses must remain an important part of healthcare. However, Schwartz and Woloshin point out that "the extent to which new 'patients' would ultimately benefit from early detection and treatment of these conditions is unknown."