Diagnostics & Imaging Week Executive Editor
SAN DIEGO — The impact of diabetes on the American populace is big — mighty big. According to the American Diabetes Association (ADA; Alexandria, Virginia), more than 18 million Americans now have diabetes, about 30% of them undiagnosed.
That being the case, it is not surprising that the annual meeting of the ADA, the largest organization focused on the disease, is equally big.
At the 65th annual scientific sessions of the association — which started Friday at the San Diego Convention Center and ended Monday — more than 2,000 papers were presented to an attendee audience totaling about 13,000 scientists, physicians and other healthcare professionals.
A report scheduled for presentation at the ADA conference on Saturday addressed the pre-diabetes population in the U.S., said to number 41 million. The association defines pre-diabetes as "a condition in which blood glucose levels are higher than normal, but not high enough for a diagnosis of diabetes," adding that "it is often a precursor of diabetes."
Gregory Nichols, PhD, senior research associate at the Kaiser Permanente Center for Health Research (Portland, Oregon), said at a Friday press conference that the use of early diagnostic testing and intervention "could lengthen lives and lower healthcare costs when pre-diabetes is spotted."
He said of such preventive medicine techniques: "Doctors should be testing people with elevated blood glucose regularly and checking for other health problems in those found to have pre-diabetes."
Pre-diabetes also is called impaired glucose tolerance (IGT) or impaired fasting glucose (IFG), depending on which test was used to detect it. The Kaiser Permanente study used IFG, for which the current cut-point for a starting diagnosis of pre-diabetes is 100 mg/dl. The cut-point for diagnosing actual diabetes is 126 mg/dl.
Prior to a change made in November 2003, the starting cut-point for pre-diabetes was 110 mg/dl. The change was made by an expert committee in order to identify more people who are at increased risk of developing Type 2 (or adult-onset) diabetes.
Nichols described in his presentation the findings of a nine-year study that looked at the healthcare costs of some 28,000 patients enrolled in Kaiser Permanente Northwest — comparing the costs of those with normal glucose levels with those with two different levels of elevated glucose, but still not yet diagnosed as being diabetic.
The two levels of elevated glucose utilized in the study included 100 mg/dl to 109 mg/dl, representing the current level for diagnosing pre-diabetes, and 110 mg/dl to 125 mg/dl, representing the previous level for such a diagnosis. The Kaiser Permanente researchers called those stage 1 and stage 2 of pre-diabetes.
For study purposes, each pre-diabetes subject was matched to another Kaiser Permanente Northwest member of the same age and sex who had normal fasting blood glucose readings.
In all, 28,335 patients were identified as having two or more IFG blood tests during the nine-year period of the study. Those with diagnosed diabetes were excluded.
All patients were followed until they: recorded a blood test qualifying them for a higher stage were diagnosed with diabetes; terminated health plan participation; or reached the end of the study on Dec. 31, 2003. Annual costs across the two pre-diabetes groups and the normal glucose readings group were then compared.
"Annual healthcare costs for those with the highest pre-diabetes blood glucose levels were 31% above those with normal blood glucose levels," Nichols said, noting that "many of the extra costs [are] due to cardiovascular disease [CVD]," including angina, heart attack, heart failure and stroke.
Costs (adjusted for age and sex) averaged $4,357 annually for those with normal glucose levels, $4,580 for those with stage 1 pre-diabetes and $4,960 among those with stage 2 pre-diabetes. When those in the normal group who later progressed to pre-diabetes or diabetes were removed from the statistical group, the average healthcare costs for those with normal blood glucose fell to $3,799 annually, thus the 31% difference, Nichols said.
While the study did not specifically address the costs for those who progressed to diabetes, Nichols said at the press conference that their healthcare costs run "50% to 75% higher than for those with normal glucose."
Characterizing CVD as "expensive to treat but far less expensive to prevent," he said that "early intervention in people with pre-diabetes is important to prevent or delay Type 2 diabetes and cardiovascular disease," and, he added, "to reduce healthcare costs for the individual and the employer."
He said that he and his research partner, Jonathan Brown, PhD, identified the allocation of healthcare costs by looking at Diagnosis-Related Group (DRG) codes. "We found a great prevalence of cardiovascular disease and obesity and therefore assume those are driving the costs," Nichols said.
The ADA said research has shown that people who are identified early as being pre-diabetic can prevent — or at least delay — progression to the disease itself by up to just under 60% through lifestyle changes that include modest weight loss and regular exercise.
Similar changes are of benefit in reducing cardiovascular disease risk.
Nichols put it emphatically: "Not only can you save money by preventing diabetes, but also by preventing patients from progressing to a higher pre-diabetes level."