The Diabetes Control and Complications Trial (DCCT, 1983-1993) compared intensive therapy aimed at near normal glycemia versus conventional therapy with no specific glucose targets in 1441 subjects with type 1 diabetes (T1DM). In 1993, after a mean follow-up of 6.5 yrs, the study showed conclusively that intensive therapy reduced the risks of retinopathy, nephropathy, and neuropathy by 35-76%, and that hyperglycemia was a primary determinant of complications. We also described potential adverse effects of intensive therapy;assessed its effects on cardiovascular disease (CVD) risk factors, neurocognition and quality of life;and projected the lifetime health-economic impact. DCCT intensive therapy was then adopted world-wide as standard-of-care for T1DM. The Epidemiology of Diabetes Interventions and its Complications (EDIC, 1994-present) is the observational follow-up study of the DCCT cohort, with 95% of those surviving actively participating. Most outcomes are evaluated annually. CVD events and deaths are carefully documented and adjudicated. EDIC has notably discovered that the early beneficial effects of intensive treatment on complications have persisted for over 10 years despite the similar HbA1c levels during EDIC in the two groups, termed metabolic memory. Notably, former intensive therapy also greatly reduced the risk of CVD events. DCCT/EDIC collaborators have also conducted numerous ancillary studies, with separate funding, most recently including measurement of cardiac function on cardiac MRI and measurement of biomarkers of oxidative stress and inflammation as determinants of complications. The overarching goals for the next 5 years are to follow at least 90% of the surviving cohort;to accurately describe the study-long effects of glycemia (HbA1c) and other established and putative risk factors on diabetes complications and the metabolic memory effects of prior DCCT intensive therapy;and to expand knowledge regarding T1DM and its complications by supporting collaborations for new research funding applications to maximally utilize the cohort, phenotypic data set, and collected biologic and genetic samples. The specific scientific aims are to 1) evaluate effects of risk factors, biomarkers and glycemia on risk of clinical CVD;2) assess the long-term changes in CVD risk factors;3) describe effects of DCCT intensive versus conventional therapy on mortality;4) evaluate risk factors for severe retinopathy and nephropathy;5) assess effects of diurnal glycemic variation on complications;and 6) conduct eight new research projects involving new measurements and analyses.

Public Health Relevance

Patients with T1DM (1,500,000 in the US) are at risk of microvascular and cardiovascular complications that are a major cause of morbidity, mortality and health care cost. The DCCT/EDIC is continuing to describe the long term benefits of intensive therapy on increasingly more severe manifestations of these complications, and to explore the mechanisms by which hyperglycemia and non-glycemic factors lead to an increased risk of these adverse complications, potentially affording a future lifetime free of complications and normal life expectancy for future generations.

National Institute of Health (NIH)
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Research Project--Cooperative Agreements (U01)
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Special Emphasis Panel (ZDK1-GRB-2 (O4))
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Leschek, Ellen W
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George Washington University
Biostatistics & Other Math Sci
Schools of Public Health
United States
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Sarma, Aruna V; Hotaling, James; Dunn, Rodney L et al. (2015) Poor glycemic control is associated with reduced prostate specific antigen concentrations in men with type 1 diabetes. J Urol 193:786-93
Genuth, Saul; Sun, Wanjie; Cleary, Patricia et al. (2015) Skin advanced glycation end products glucosepane and methylglyoxal hydroimidazolone are independently associated with long-term microvascular complication progression of type 1 diabetes. Diabetes 64:266-78
Diabetes Control and Complications Trial (DCCT)/Epidemiology of Diabetes Interventions and Complications (EDIC) Research Group; Lachin, John M; White, Neil H et al. (2015) Effect of intensive diabetes therapy on the progression of diabetic retinopathy in patients with type 1 diabetes: 18 years of follow-up in the DCCT/EDIC. Diabetes 64:631-42
Miao, Feng; Chen, Zhuo; Genuth, Saul et al. (2014) Evaluating the role of epigenetic histone modifications in the metabolic memory of type 1 diabetes. Diabetes 63:1748-62
Simpson, Claire L; Wojciechowski, Robert; Oexle, Konrad et al. (2014) Genome-wide meta-analysis of myopia and hyperopia provides evidence for replication of 11 loci. PLoS One 9:e107110
Lachin, John M; Orchard, Trevor J; Nathan, David M et al. (2014) Update on cardiovascular outcomes at 30 years of the diabetes control and complications trial/epidemiology of diabetes interventions and complications study. Diabetes Care 37:39-43
Buschur, Elizabeth; Sarma, Aruna V; Pietropaolo, Massimo et al. (2014) Self-reported autoimmune disease by sex in the diabetes control and complications trial/epidemiology of diabetes interventions and complications (DCCT/EDIC) study. Diabetes Care 37:e28-9
de Boer, Ian H; Afkarian, Maryam; Rue, Tessa C et al. (2014) Renal outcomes in patients with type 1 diabetes and macroalbuminuria. J Am Soc Nephrol 25:2342-50
McGee, P; Steffes, M; Nowicki, M et al. (2014) Insulin secretion measured by stimulated C-peptide in long-established Type 1 diabetes in the Diabetes Control and Complications Trial (DCCT)/ Epidemiology of Diabetes Interventions and Complications (EDIC) cohort: a pilot study. Diabet Med 31:1264-8
Nathan, David M; DCCT/EDIC Research Group (2014) The diabetes control and complications trial/epidemiology of diabetes interventions and complications study at 30 years: overview. Diabetes Care 37:9-16

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