Diabetes Control and Complications Trial (DCCT) and Epidemiology of Diabetes Interventions and Complications Study (EDIC)

The Diabetes Control and Complications Trial (DCCT, 1982-93) and the Epidemiology of Diabetes Interventions and Complications follow-up study (EDIC, 1994-2016) have been ongoing for more than twenty years. After a mean follow-up of approximately 16 years, the DCCT-EDIC cohort of 1,441 Type 1 diabetics had remained remarkably complete with more than 90% of the original cohort being actively followed. Taken together, the DCCT clinical trial and subsequent EDIC longitudinal follow-up provide a uniquely rich source of information on the impact of intensive therapy on glycemia and the its long-term complications for persons with Type 1 diabetes.

The DCCT was a multicenter, randomized clinical trial (1, 2) designed to compare intensive with conventional diabetes therapy with regard to their effects on the development and progression of the early complications of Type 1 diabetes. The DCCT trial found that "intensive therapy effectively delays the onset and slows the progression of diabetic retinopathy, nephropathy, and neuropathy" in patients with Type 1 diabetes (1). The goal of the EDIC follow-up was to examine the longer term effects of the original DCCT interventions, especially as they apply to late-occurring complications, such as cardiovascular disease and more advanced stages of retinal and renal disease (3). The EDIC study has been remarkably fruitful in discovering the long term "imprinting" effects (metabolic memory) of the previous intensive therapy, and in delineating the interactions among risk factors with regard to microvascular complications (4-6). In addition, EDIC established, for the first time, the role of intensive therapy and chronic glycemia on atherosclerosis (7-9).

Note: This study description has been prepared using materials authored by the DCCT-EDIC Data Coordinating Center.

DETAILED DESCRIPTION OF STUDY

• Study Weblinks:
  • NIDDK
  • NIDDK DCCT
  • NIDDK EDIC
  • The Biostatistics Center - EDIC
  • NIDDK Central Repository
• Study Design:
  • Clinical Trial
• Study Type:
  • Clinical Trial
  • Longitudinal
• dbGaP estimated ancestry using GRAF-pop
• Total number of consented subjects: 1497
• Subject Sample Telemetry Report (SSTR)

• BioProject
• PubMed
• BioSample
• MeSH
• PMC
• Clinical Trials
  • NCT00360815
  • NCT00360893

The major criteria for eligibility included insulin dependence, as evidenced by deficient C-peptide secretion; an age of 13 to 39 years; and the absence of hypertension, hypercholesterolemia, and severe diabetic complications or medical conditions. To be eligible for the primary-prevention cohort, patients were required to have had IDDM for one to five years, to have no retinopathy as detected by seven-field stereoscopic fundus photography, and to have urinary albumin excretion of less than 40 mg per 24 hours. To be eligible for the secondary intervention cohort, the patients were required to have had IDDM for 1 to 15 years, to have very mild-to-moderate nonproliferative retinopathy, and to have urinary albumin excretion of less than 200 mg per 24 hours. (Excerpted from 1993 study report in NEJM, PMID: 8366922.)

FURTHER DETAILS ON CRITERIA

• Primary Phenotype: Insulin-Dependent Diabetes Mellitus
• Diabetic Retinopathy
• Diabetic Neuropathies
• Diabetic Nephropathies