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ORLANDO, FLA. -- In the largest study of diabetes and
depression conducted to date, researchers at Duke University
Medical Center have found a clear link between the complexity
of the self-care regimens in patients with diabetes and the
effect of depression on diabetes control. They said the
findings could help settle a long-standing debate among
clinicians over whether a link between depression and diabetes
control exists.

According to the researchers, depressed diabetic patients
who take three or more insulin shots per day are at much
greater risk of being in poor metabolic control than are
depressed patients who require no insulin or less insulin.
While depression only affects diabetes control in some
patients, those who require higher amounts of insulin should
pay more strict attention to symptoms of depression, they
added.

"We know that patients who require more insulin on a daily
basis have less residual pancreatic activity and a more
difficult time regulating their glucose levels," said Richard
Surwit, Ph.D., vice-chairman of research in the department of
psychiatry and behavioral medicine at Duke. "Their metabolic
control is going to be more vulnerable to disruption by
behavioral and neuroendocrine factors. This means that at any
level of depression, diabetics who experience more difficulty
regulating their glucose levels are more likely to get thrown
even farther off balance by depression."

Surwit prepared his group's findings for presentation June
5, 2004, at the 64th annual scientific sessions of the American Diabetes
Association.

More than 1,000 adults 18 years or older with diabetes were
recruited to participate in the study. The participants were
all members of a local Health Maintenance Organization (HMO) in
Durham, N.C. The HMO contacted all diabetes patients they were
serving and invited them to participate. Of the 1,034 patients
who agreed, at their next routine examination all were
administered a hemoglobin A1c (HbA1c) test to measure their
glucose levels. Afterward, patients were sent a depression
assessment form, called a Beck Depression Inventory.

Surwit's research team compared the relationship of
depression to diabetes control among participants based upon
treatment regimens. The patients fell into natural groupings
based on their treatment programs:

-- diet and exercise only
-- oral medications only
-- oral medications and insulin
-- one to two insulin injections daily
-- three or more daily injections of insulin

The researchers found no correlation between depressive
symptoms and glycemic control in patients taking fewer than
three insulin shots per day, regardless of their type of
diabetes. However, there was a strong correlation between
depressive symptoms and glycemic control in those patients with
the more complex regimen of taking three or more insulin shots
per day.

"Patients who have more complex self-care regimens,
particularly those who are taking three or more insulin shots
per day should pay close attention to shifts in mood," Surwit
added. "And physicians who are treating people who fall into
this category should be regularly monitoring them for signs of
depression. Depression is treatable, but left untreated the
greater the patient's vulnerability to extreme glucose
fluctuations."

According to 2002 statistics provided by the National Institute of Diabetes
& Digestive & Kidney Diseases, approximately 18.2
million people in the U.S. have diabetes, at a total direct and
indirect cost of $132 billion per year. Complications of
diabetes include heart disease and stroke, high blood pressure,
blindness and kidney disease. Previous research has shown that
approximately 30 percent of adult patients with diabetes report
experiencing clinically significant depressive symptoms.
Depressive symptoms in these patients are associated with
reduced quality of life, impaired physical functioning,
increased diabetic complications and increased medical
costs.

Research funding was provided through an educational grant
from Pfizer, Inc. but the grant was not used to examine any
Pfizer product or service.

Other authors on the study include Miranda A.L. Van Tilburg,
Ph.D.; Priti I. Parekh, Ph.D.; James D. Lane, Ph.D. and Mark
Feinglos, M.D.. Surwit owns stock in Pfizer, Inc.

Surwit is author of "The Mind-Body Diabetes Revolution: A
Proven New Program for Better Blood Sugar Control," published
in 2004 by Free Press, a subsidiary of Simon & Schuster,
Inc.