Oscar Crofford: On the horns of a revolution pg. 4
What made the diabetes study so difficult was that it would require the participation of more than 1,000 patients at multiple research centers over the course of several years.
Despite his relative inexperience, Crofford was a natural to lead the study, his colleagues say. He had continued to advise the NIH on the direction of diabetes research and, in 1981-1982, he served as ADA president. “He was on the ground floor, both from the scientific and public policy aspects,” says Dr. Phillip Gorden, who directed the National Institute of Diabetes and Digestive and Kidney Diseases from 1986 to 1999.
In addition to scientific curiosity, Crofford was motivated by empathy for the plight of his patients. “He saw people having terribly devastating complications from diabetes,” says Vanderbilt research nurse Janie Lipps, who worked with him on the trial and who continues to follow some of the participants. “He wanted to know the truth. Does (controlling blood glucose) really matter?”
This was not the first time that scientists had tried to answer the question.
In 1970 another U.S. study, the University Group Diabetes Program, found no benefit in controlling blood glucose in type 2 diabetics. But it was hampered by the lack of a reliable method for measuring chronic high blood glucose. The hemoglobin A1c test would not become available for several years.
Hemoglobin is the protein in red blood cells that transports oxygen to body tissues. A form of the protein also can bind to glucose, and carry it around for several weeks. Measuring hemoglobin A1c, then, is a way of determining a person’s average blood glucose level over a two- to three-month period.
“That was a very important tool for the clinical trial,” says Dr. David M. Nathan, who, as a young investigator at Harvard Medical School, had helped develop the hemoglobin A1c test. “It gave you this wonderful … timed window on average blood sugar control in a single measurement.”
Two other developments in the 1970s made the study possible: portable glucose monitors, which enabled patients to check their blood glucose conveniently and accurately; and new forms of insulin and insulin pumps, which made it easier for patients to keep their blood glucose within the normal range.
By the early 1980s, the pieces “were all falling into place,” says Nathan, now a professor of Medicine at Harvard and director of the Diabetes Center at Massachusetts General Hospital.
Nathan’s center was one of 29 across the United States and Canada that participated in the study, which focused on patients with type 1 diabetes who had not yet developed complications of the disease, or who had only mild retinopathy, the overgrowth of blood vessels in the retina of the eye that can cause blindness.
Between 1983 and 1989, more than 1,400 participants were enrolled, making the Diabetes Control and Complications Trial (DCCT) one of the largest studies of diabetes ever undertaken.
View Related Article: