Diabetes Trial Shows Prevention Benefits Two Decades Later

New data released today from the Diabetes Prevention Program Outcomes Study (DPPOS) shows that in over 2000 patients followed for an average of 22 years, lifestyle programs and treatment with metformin continues to prevent the development of type 2 diabetes (T2D) in at risk populations.

The results, New Data on Clinical Outcomes from the Diabetes Prevention Program Outcomes Study (DPPOS), were presented today at the American Diabetes Association’s® (ADA’s) 80th Virtual Scientific Sessions.

The DPPOS is the long-term follow-up of the Diabetes Prevention Program (DPP), a multicenter trial conducted from 1996 to 2001 that established the success of either an intensive lifestyle program or treatment with metformin to prevent or delay the development of T2D in individuals who were considered at high risk for developing the disease. The DPP demonstrated lifestyle intervention, aimed at achieving weight loss, and metformin treatment reduced the risk of T2D development by 58% and 31%, respectively, compared to placebo after an average of three years. Metformin, one of the most commonly used medications worldwide for the treatment of T2D, is currently not labeled by the FDA for prevention purposes, although it is approved in other countries.

88% of the original 3,234 DPP participants enrolled in the DPPOS, including the DPP participants who had developed T2D and those who still had not developed diabetes. Currently, after an average of 22 years of study, 75% of the participants who enrolled in the DPP who are still alive have continued to be evaluated. The mean age of the participants is now 72 years.

The newest results indicate that prevention effects in the original lifestyle group and metformin treatment group remain 22 years after the start of the study with a 25% and 18% reduced risk of diabetes development, respectively, compared with the original placebo group.

“The DPP/DPPOS is the longest duration and largest prevention study that continues to actively follow its participants,” said DPPOS chair David M. Nathan, MD, director of the Clinical Research Center and Diabetes Center at Massachusetts General Hospital and professor of medicine at Harvard Medical School. “The current results indicate that prevention of type 2 diabetes is possible and has important clinical benefits. The long-term benefits of the two DPP interventions on diabetes development, still present many years after they were started, are a testament to the power of these interventions and reinforce their importance in the reduction of diabetes.”

The participants who did not develop diabetes had a significant (57% and 37%) lower risk of developing early changes of eye and kidney disease, respectively, and a 39% lower risk of major cardiovascular disease endpoints, such as heart attacks and stroke.

There was no significant benefit in heart disease or the development of kidney disease or diabetic retinopathy with either of the individual interventions—metformin or the lifestyle intervention.However, stroke and cardiovascular events were reduced in the subgroup of people who started the study before age 45, and there was a non-significant (12%) lower risk of cancer in the Metformin group compared with the placebo group. The intensive lifestyle intervention group also had a long-term reduction in the development of frailty.

There was a modest increase in kidney disease with metformin, which appeared only in the oldest group of participants.