"What this shows is that none of the strategies in the study can be recommended" as being superior to the other, said Dr. Graham T. McMahon, an assistant professor of medicine at Brigham and Women's Hospital in Boston, and co-author of an editorial accompanying the report, published online Friday in the New England Journal of Medicine.
A study designed to tell which insulin-plus-drug regimen might best control type 2 diabetes has produced disappointing preliminary results, with none of the three strategies tested coming out on top.
Instead, he said, the insulin regimen would probably have to be tailored to each patient, McMahon said.
The report was released early, because the preliminary, one-year results of the four-year study are being presented at a meeting of the European Association for the Study of Diabetes, in Amsterdam.
The study, led by British diabetes specialists at the University of Oxford, included 708 participants with type 2 diabetes. Type 2 diabetes, which affects about 95 percent of diabetics, typically occurs in adulthood and is often tied to obesity.
All of the trial participants were given maximum doses of two diabetes drugs, metformin and sulfonylurea, and a different regimen of injected insulin three times a day, two times a day or just once a day. The once-a-day group got an extra dose if deemed necessary.
The goal was to reduce blood levels of glycolated hemoglobin, which forms when sugar enters blood cells, to 6.5 percent or less.
The results overall were not impressive: The treatment goal was achieved by just 23.9 percent of those getting insulin three times a day, 17 percent of those getting insulin twice a day and 8.1 percent of those in the once-a-day group, the researchers reported.
Still, the results indicated that "the best thing to be done is to follow current guidelines," McMahon said. That means "using long-acting drugs and adding insulin either once, twice or three times a day," he said, depending on each patient's particular needs.
The greater success rate in the two- and three-times-a-day regimen had a down side, the team noted, since it was also accompanied by an increased incidence of weight gain and low blood sugar levels, the report said.
Diabetes control "is hard work for doctor and patient," Deeb said, and "family doctors have got to learn to give insulin the way we endocrinologists do." Deeb is located in Tallahassee, Fla., where the ratio of endocrinologists is 1 to 75,000 inhabitants, he noted.
Family doctors can handle type 2 diabetes, McMahon said, but it is best if they do not work alone. "An endocrinologist, nutritionist and nurse-educator should cooperate," he said.
Because type 2 diabetes is a major risk factor for heart disease, attention should be paid not only to blood sugar levels but also to other coronary risk factors, such as blood pressure and cholesterol levels, McMahon said.