The George Washington University Biostatistics Center and collaborators from across the United States published research showing that people who 21 years ago were given either intensive lifestyle interventions or the daily use of the diabetes medication metformin show significant reductions in Type 2 diabetes. The Diabetes Prevention Program Outcomes Study (DPPOS) is the first study to demonstrate a long-lasting return on investment in diabetes prevention efforts.
Study participants were adults at high risk of developing diabetes. Those given lifestyle interventions reduced their risk of developing diabetes by 24%, while participants given metformin reduced their diabetes risk by 17%.
DPPOS is an outgrowth of the U.S. Diabetes Prevention Program (DPP), a major clinical research study that began in the 2000s. The original DPP study discovered that either intensive lifestyle changes or daily use of the medication metformin reduced the onset of Type 2 diabetes over the first few years. Lifestyle change yielded a 58% reduction, compared to a 31%reduction for metformin.
The follow up of 3,195 DPP participants highlights the long-term benefits of these interventions in preventing the development of diabetes. Compared with the original placebo group, the median time without diabetes was extended by 3.5 years in the lifestyle group and 2.5 years in the metformin group.
“The DPP and the DPPOS studies have made remarkable discoveries about how the onset and consequences of diabetes can be prevented, a critical public health issue in the context of a disease that has more than doubled in the last 30 years and causes so much death and disability,” said Lynn Goldman, the Michael and Lori Milken Dean of GW’s Milken Institute School of Public Health.
It's long been conventional wisdom that children should be encouraged to eat their vegetables and exercise more, Goldman said. “Now, we have scientific proof that even if you wait until midlife to change your diet and activity levels, you can add many years of life free from diabetes and all the disabling conditions that come along with it.”
Diabetes prevention not only extends life, but also reduces secondary conditions caused by Type 2 diabetes like kidney failure, limb amputation, blindness, heart disease and stroke, Goldman said.
Researchers at the GW University Biostatistics Center, which is based at the Milken Institute SPH, along with researchers from the National Institutes of Health and 28 other institutions and clinical sites across the U.S., published the study April 28 in the journal The Lancet Diabetes & Endocrinology.
The original DPP clinical trial started in 1996, when participants were on average 51 years old. About 45% identified as members of U.S. minority groups especially affected by type 2 diabetes. The long-term benefits of the two interventions extended across all racial and ethnic groups included in the study.
The positive effects seen in the first few years of the trial led to the adoption, in the United States and globally, of diabetes prevention programs modelled on the DPP that focus on improving lifestyle and nutrition. While maintaining long-term intensive lifestyle and medicine interventions can be challenging, this latest study shows that even short-term interventions have long-lasting benefits.
The GW Biostatistics Center coordinated the two large, multi-center nationwide studies and managed and analyzed data from the other participating institutions and clinical sites.
“DPP and the follow-up DPPOS study have benefited from the collective dedication of participants at clinical sites across the U.S. and continued to show that lifestyle and metformin are effective diabetes preventive strategies,” said Marinella Temprosa, an associate research professor of biostatistics and bioinformatics at GW who led the team at the GW Biostatistics Center.
NIH’s National Institute of Diabetes and Digestive and Kidney Diseases funded both the DPP and the DPPOS studies. NIH’s National Institute of Aging has also supported an extension of the DPPOS, which has been evaluating whether lifestyle changes in participants protect people from age-related conditions, including Alzheimer’s disease and cancer.
“We are grateful to the NIH for their past support of this work,” Goldman said. “Studies like these—long-term, multi-year, multi-center trials involving thousands of participants across the U.S.—have been made possible by the sustained investment of the federal government in research. In this case and in many others, that investment has delivered invaluable, often lifesaving health insights that keep people healthy and benefit the nation. We remain hopeful that the federal government will continue to support critical studies like the DPPOS so investigators can address key questions about prevention of dementia, cancer and other diseases.”
