(HealthDay)—A study of nearly a half-million people with type 2 diabetes shows there are pros and cons to nearly every form of drug therapy for the disease.
In the British study, researchers looked at patient outcomes from a large U.K. database of almost 470,000 adults with type 2 diabetes, tracked between 2007 and 2015.
Julia Hippisley-Cox and Carol Coupland, of the University of Nottingham, sought to parse out differences among a variety of diabetes drugs. They accounted for complicating patient factors such as age, sex, smoking and poverty, as well as how long a person had been diagnosed with type 2 diabetes.
The researchers also focused on five major outcomes linked to diabetes: blindness, amputation, severe kidney failure, and high or low blood sugar.
Reporting March 30 in BMJ, they found that when a class of drugs called glitazones (Actos, Avandia) was prescribed along with the standard diabetes drug metformin, there was a higher risk for kidney failure than with metformin alone.
The same was true when another class of meds called gliptins (Januvia, Onglyza and others) was combined with metformin.
However, there were "up" sides to these drug combos as well. People who took a gliptin or a glitazone plus metformin had "significantly lower" risks for high blood sugar than those who took metformin alone, the research found.
Finally, the study looked at "triple" therapy: patients taking metformin, a gliptin or a glitazone, and a sulphonylurea, another type of diabetes drug. This combination was linked to "significantly higher" odds for episodes of potentially dangerous low blood sugar, the British researchers said, compared to people taking metformin alone.
On the other hand, triple-therapy users had a reduced risk for diabetes-linked blindness, compared to the metformin-only group.
The study doesn't establish direct cause-and-effect relationships between the various drugs and these outcomes. Still, according to experts, the findings support the notion that diabetes care is never a "one-size-fits-all" endeavor.
"There are many treatment options for diabetes—they have the benefit of lowering blood sugar levels, but they also carry risk," said Dr. Robert Courgi, an endocrinologist at Northwell Health's Southside Hospital in Bay Shore, N.Y.
He said that standard guidelines typically list metformin as a first-line therapy against type 2 disease, but additional drugs may be needed. "Ultimately, the physician and the patient need to work together to find the best treatment possible," Courgi said.
Dr. Gerald Bernstein coordinates the Friedman Diabetes Program at Lenox Hill Hospital in New York City. He believes the field of diabetes care is constantly evolving.
"Treating type 2 diabetes used to be like a singles pingpong game—give a pill, lower blood sugar," he said.
However, "over the last 75 years or so we have learned that it is more of a team effort, because the process of safely lowering blood sugar is more complicated than previously thought," Bernstein explained. "The goal of treatment for all diabetes is to prevent complications and have a high quality of life."
Different medications have different targets and effects, he said, and "the art of treatment today mixes and matches these medications depending on age, weight, activity."
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For more on the treatment of type 2 diabetes, head to the American Diabetes Association.