The NIDDK conducts research in its own laboratories and supports a great deal of basic and clinical research in medical centers and hospitals throughout the United States. It also gathers and analyzes statistics about diabetes. Other Institutes at the NIH conduct and support research on diabetes-related eye diseases, heart and vascular complications, autoimmunity, pregnancy, and dental problems.
Other Government agencies that sponsor diabetes programs are the CDC, the Indian Health Service, the Health Resources and Services Administration, the Department of Veterans Affairs, and the Department of Defense.
Many organizations outside the Government support diabetes research and education activities. These organizations include the American Diabetes Association (ADA), the Juvenile Diabetes Research Foundation International (JDRF), and the American Association of Diabetes Educators.
In recent years, advances in diabetes research have led to better ways of managing diabetes and treating its complications. Major advances include
- development of quick-acting and long-acting insulins
- better ways to monitor blood glucose and for people with diabetes to check their blood glucose levels
- development of external insulin pumps that deliver insulin, replacing daily injections
- laser treatment for diabetic eye disease, reducing the risk of blindness
- successful kidney and pancreas transplantation in people whose kidneys fail because of diabetes
- better ways of managing diabetes in pregnant women, improving their chances of a successful outcome
- new drugs to treat type 1 and type 2 diabetes and better ways to manage these forms of diabetes through weight control
- evidence that intensive management of blood glucose reduces and may prevent development of diabetes complications
- demonstration that two types of antihypertensive drugs, angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs), are more effective than other antihypertensive drugs in reducing a decline in kidney function in people with diabetes
- advances in transplantation of islets—clusters of cells that produce insulin and other hormones—for type 1 diabetes
- evidence that people at high risk for type 2 diabetes can lower their chances of developing the disease through diet, weight loss, and physical activity
What will the future bring?
Researchers continue to look for the cause or causes of diabetes and ways to manage, prevent, or cure the disorder. Scientists are searching for genes that may be involved in type 1 or type 2 diabetes. Some genetic markers for type 1 diabetes have been identified, and it is now possible to screen relatives of people with type 1 diabetes to determine whether they are at risk.
Type 1 Diabetes
A number of federally funded research studies and clinical trials are under way. Studies focus on the prevention and causes of type 1 diabetes as well as experimental treatments such as islet transplantation.
Diabetes Prevention Trial–Type 1 (DPT–1)
The NIDDK and other groups sponsored DPT–1, which showed that people at risk for developing type 1 diabetes can be identified. The DPT–1 researchers discovered ways to identify two populations at risk of developing type 1 diabetes within 5 years—those at high risk, with at least a 50 percent chance, and those at intermediate risk, with a 25 to 50 percent risk. Then researchers explored possible ways of preventing type 1 diabetes in both groups. Although the study found that neither low-dose insulin injections nor insulin capsules taken orally prevented or delayed type 1 diabetes in the study population, research that follows up on DPT–1 findings is under way. For more information about DPT–1, see www.niddk.nih.gov/patient/dpt_1/dpt_1.htm.
The NIDDK and other groups sponsored DPT–1, which showed that people at risk for developing type 1 diabetes can be identified. The DPT–1 researchers discovered ways to identify two populations at risk of developing type 1 diabetes within 5 years—those at high risk, with at least a 50 percent chance, and those at intermediate risk, with a 25 to 50 percent risk. Then researchers explored possible ways of preventing type 1 diabetes in both groups. Although the study found that neither low-dose insulin injections nor insulin capsules taken orally prevented or delayed type 1 diabetes in the study population, research that follows up on DPT–1 findings is under way. For more information about DPT–1, see www.niddk.nih.gov/patient/dpt_1/dpt_1.htm.
The Environmental Determinants of Diabetes in the Young (TEDDY) Consortium
The main mission of the TEDDY consortium, an international group of clinical centers, is to identify infectious agents, dietary factors, or other environmental factors—including psychosocial events—that trigger type 1 diabetes in those who are genetically susceptible. In addition, the consortium aims to
- create a central repository of data and biological samples for use by researchers
- develop novel approaches to finding the causes of type 1 diabetes
- find ways to understand how the disease starts and progresses
- discover new methods to prevent, delay, and reverse type 1 diabetes
TEDDY is funded by the NIDDK, the National Institute of Allergy and Infectious Diseases (NIAID), the National Institute of Child Health and Human Development (NICHD), the National Institute of Environmental Health Sciences, the CDC, the JDRF, and the ADA. For more information, see http://teddy.epi.usf.edu.
Type 1 Diabetes Genetics Consortium (T1DGC)
The T1DGC is a group of researchers from around the world who are studying the genetics of type 1 diabetes. They are studying families with siblings who have type 1 diabetes to look for genes that may show a person’s risk of getting type 1 diabetes or might keep someone from getting type 1 diabetes. For more information, see www.t1dgc.org.
The T1DGC is a group of researchers from around the world who are studying the genetics of type 1 diabetes. They are studying families with siblings who have type 1 diabetes to look for genes that may show a person’s risk of getting type 1 diabetes or might keep someone from getting type 1 diabetes. For more information, see www.t1dgc.org.
Type 1 Diabetes TrialNet
Type 1 Diabetes TrialNet is a network of experts and facilities dedicated to developing new approaches to the understanding, prevention, and treatment of type 1 diabetes. Clinical centers are located in the United States, Canada, Europe, and Australia.
Type 1 Diabetes TrialNet is a network of experts and facilities dedicated to developing new approaches to the understanding, prevention, and treatment of type 1 diabetes. Clinical centers are located in the United States, Canada, Europe, and Australia.
TrialNet studies are focusing on
- understanding the natural history of type 1 diabetes to determine its causes and progression
- preventing type 1 diabetes in those at risk
- developing ways to preserve the function of the insulin-producing cells in the pancreas in people recently diagnosed with type 1 diabetes
For more information, see www.DiabetesTrialNet.org or call 1–800–HALT–DM1 (425–8361).
TrialNet will identify people at risk who may be eligible for clinical trials. In addition, TrialNet will conduct trials to save beta cell function in those with new onset type 1 diabetes.
TrialNet is funded by the NIDDK, NICHD, and NIAID. The JDRF and ADA also support this effort.
The Immune Tolerance Network
TrialNet works closely with the Immune Tolerance Network, another international, collaborative consortium. Its goal is to find safe and effective ways to induce long-term immune tolerance—prevention of an unwanted immune response by the body. For example, type 1 diabetes might be prevented if scientists could learn how to prevent the immune system from mistakenly attacking the insulin-producing cells in the pancreas. Effective immune tolerance could possibly
- prevent the body’s rejection of organ or tissue transplants
- prevent or treat autoimmune diseases
- prevent or treat allergies and asthma
For more information, see www.immunetolerance.org or call 415–514–2530.
The Trial to Reduce IDDM in the Genetically at Risk (TRIGR)
The TRIGR study will help determine whether delayed exposure to cow’s milk can prevent type 1 diabetes in infants at risk of developing the disease. Instead of receiving cow’s milk, infants in the TRIGR study will primarily breastfeed. Babies whose mothers cannot breastfeed will be given a special formula made with milk proteins that may be easier for babies to tolerate. The TRIGR study will help clarify whether infant feeding practices are related to the development of diabetes. For more information, see www.trigrnorthamerica.org or call 1–888–STOP–T1D (786–7813).
The TRIGR study will help determine whether delayed exposure to cow’s milk can prevent type 1 diabetes in infants at risk of developing the disease. Instead of receiving cow’s milk, infants in the TRIGR study will primarily breastfeed. Babies whose mothers cannot breastfeed will be given a special formula made with milk proteins that may be easier for babies to tolerate. The TRIGR study will help clarify whether infant feeding practices are related to the development of diabetes. For more information, see www.trigrnorthamerica.org or call 1–888–STOP–T1D (786–7813).
Islet Transplantation
Researchers are working on a way for people with type 1 diabetes to live without daily insulin injections. In an experimental procedure called islet transplantation, islets are taken from a donor pancreas and transferred into a person with type 1 diabetes. Once implanted, the beta cells in these islets begin to make and release insulin.
Although scientists have made many advances in islet transplantation in recent years, transplanted islets tend to lose function over time, and few transplant recipients are able to stop using insulin for very long. But even partial islet function can help patients reduce their need for insulin, achieve better glucose stability, and reduce problems with hypoglycemia.
Problems with islet transplantation include the severe shortage of islets available for transplants and the need for patients to take drugs with significant side effects to stop the immune system from rejecting the transplanted islets. Researchers are seeking solutions to these problems.
For more information about islet transplantation, see the fact sheet Pancreatic Islet Transplantation at www.diabetes.niddk.nih.gov/dm/pubs/pancreaticislet.
Type 2 Diabetes
Diabetes Prevention Program
In 1996, the NIDDK launched its Diabetes Prevention Program (DPP). The goal of this research effort was to learn how to prevent or delay type 2 diabetes in people with impaired glucose tolerance, a strong risk factor for type 2 diabetes.
In 1996, the NIDDK launched its Diabetes Prevention Program (DPP). The goal of this research effort was to learn how to prevent or delay type 2 diabetes in people with impaired glucose tolerance, a strong risk factor for type 2 diabetes.
The findings of the DPP, released in August 2001, showed that people at high risk for type 2 diabetes could sharply lower their chances of developing the disorder through diet and exercise. In addition, treatment with the oral diabetes drug metformin also reduced diabetes risk, though less dramatically. Metformin lowers the amount of glucose released by the liver and also fights insulin resistance, a condition in which the body doesn’t use insulin properly.
Participants randomly assigned to intensive lifestyle intervention reduced their risk of getting type 2 diabetes by 58 percent. On average, this group maintained their physical activity at 30 minutes per day, usually with walking or other moderate intensity exercise, and lost 5 to 7 percent of their body weight. Participants randomized to treatment with metformin reduced their risk of getting type 2 diabetes by 31 percent.
Of the 3,234 participants enrolled in the DPP, 45 percent were from minority groups that suffer disproportionately from type 2 diabetes: African Americans, Hispanics/ Latinos, Asian Americans and Pacific Islanders, and American Indians. The DPP also recruited other groups known to be at higher risk for type 2 diabetes, including individuals ages 60 or older, women with a history of gestational diabetes, and people with a first-degree relative with type 2 diabetes.
Participants are still being followed to check for long-term effects of the interventions, including the effects on CVD. Recent analyses of data from the DPP have added to the evidence that lifestyle changes are especially effective in helping to reduce the risk of developing conditions associated with type 2 diabetes, including high blood pressure and the metabolic syndrome. Researchers also confirmed that study participants carrying two copies of a gene variant that significantly increased their risk of developing diabetes benefited from lifestyle changes as much as or more than those without the gene variant.
Type 2 Diabetes in Children and Teens
Two studies focusing on type 2 diabetes in children and teens are under way. The Treatment Options for type 2 Diabetes in Adolescents and Youth (TODAY) study, a 13-site study sponsored by the NIDDK, will compare treatments for type 2 diabetes in children and teens. Participants will undergo one of three treatments:
- taking one diabetes medication—metformin
- taking two diabetes medications—metformin and rosiglitazone, another medication that fights insulin resistance
- taking metformin and participating in an intensive lifestyle change program designed to promote weight loss by cutting calories and increasing physical activity
The main goal of the study is to determine how well each type of treatment controls blood glucose levels. The study also will evaluate how long each type of treatment is effective.
Current NIDDK-sponsored research includes the HEALTHY study, which is part of a broad research initiative called STOPP T2D (Studies to Treat or Prevent Pediatric Type 2 Diabetes). The study explores whether improving nutrition, promoting physical activity, and making changes in behavior can lower risk factors for type 2 diabetes in children from 42 middle schools across the country. Participating schools are randomly assigned to a program group, which implements the changes, or to a comparison group, which continues to offer food choices and physical education programs typically found in middle schools across the country. Students in the program group will have healthier choices available in the cafeteria and vending machines; longer, more intense periods of physical activity; and activities and awareness campaigns that promote long-term healthy behaviors. Results from the HEALTHY study are expected in 2009.
Preventing and Treating CVD in People with Type 2 Diabetes
CVD is the main killer of people with type 2 diabetes. For this reason, the NIH is studying the best strategies to prevent and treat CVD in people with diabetes in three major studies. These studies are all joint efforts of the NIDDK and the National Heart, Lung, and Blood Institute (NHLBI).
CVD is the main killer of people with type 2 diabetes. For this reason, the NIH is studying the best strategies to prevent and treat CVD in people with diabetes in three major studies. These studies are all joint efforts of the NIDDK and the National Heart, Lung, and Blood Institute (NHLBI).
The Look AHEAD (Action for Health in Diabetes) trial is the largest clinical trial to date to examine the long-term health effects of voluntary weight loss. This multicenter, randomized clinical trial is studying the effects of a lifestyle intervention designed to achieve and maintain weight loss over the long-term through decreased caloric intake and increased exercise. Look AHEAD will focus on the disorder most associated with being overweight or obese, type 2 diabetes, and on the outcome that causes the greatest morbidity and mortality in people with type 2 diabetes, CVD. Results after 1 year of the study show that people receiving the lifestyle intervention lost an average of 8.6 percent of their initial body weight. In addition, they showed improved control of diabetes as well as improvements in cardiovascular risk factors, such as high blood pressure and blood fat levels.
The Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial, a multicenter, randomized trial, is studying three approaches to preventing major cardiovascular events in individuals with type 2 diabetes. ACCORD was designed to compare current practice guidelines with more intensive glycemic control in 10,000 individuals with type 2 diabetes, including those at especially high risk for cardiovascular events because of age, evidence of subclinical atherosclerosis, or existing clinical CVD. More intensive control of blood pressure than is called for in current guidelines and a medication to reduce triglyceride levels and raise HDL, or “good,” cholesterol levels will also be studied in subgroups of these 10,000 volunteers. Each treatment strategy will be accompanied by standard advice regarding lifestyle choices, including diet, physical activity, and smoking cessation, appropriate for individuals with diabetes.
The primary outcome to be measured is the first occurrence of a major cardiovascular event, specifically heart attack, stroke, or cardiovascular death. In addition, the study will investigate the impact of the treatment strategies on other cardiovascular outcomes; total mortality; limb amputation; eye, kidney, or nerve disease; health-related quality of life; and cost-effectiveness.
In February 2008, the NHLBI decided to stop one part of the study—the intensive glycemic control treatment—before the end of the entire trial because of safety concerns. However, the trial will continue with the other treatments until the planned end in 2009.
The Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial, a 5-year, multicenter clinical trial, is comparing medical versus early surgical management of patients with type 2 diabetes who also have coronary artery disease and stable angina or ischemia. At the same time, BARI 2D will study the effect of two different strategies to control blood glucose—providing insulin versus increasing the sensitivity of the body to insulin—on the risk of cardiovascular mortality and morbidity.
Participants in clinical trials can play a more active role in their own health care, gain access to new research treatments before they are widely available, and help others by contributing to medical research. For information about current studies,
visit www.ClinicalTrials.gov.
Points to Remember
What is diabetes?
- a disorder of metabolism—the way the body uses or converts food for energy and growth
What are the main types of diabetes?
- type 1 diabetes
- type 2 diabetes
- gestational diabetes
What is the impact of diabetes?
- It affects 23.6 million people—7.8 percent of the U.S. population.
- It is a leading cause of death and disability.
- It costs billion per year.
Who gets diabetes?
- people of any age
- people with a family history of diabetes
- others at high risk for type 2 diabetes: older people, overweight and sedentary people, African Americans, Alaska Natives, American Indians, Asian Americans, Native Hawaiians, some Pacific Islander Americans, and Hispanics/Latinos
