Autoimmune destruction of the pancreatic beta cells is the major cause of type 1 diabetes.
Type 1 diabetes is a genetically determined disorder; the genes responsible are within the major histocompatibility complex locate on chromosome 6.
Evidence of residual insulin secretion is present in 45% of adult (ages 18-39 years) within 5 years after the onset of type 1 diabetes and 11% retain some secretory capacity after 5 years of type 1 diabetes.
Intensive hypoglycemic therapy may result in the maintenance of some inssulin secretory capacity. This is associated with improved metabolic control, less hypoglycemia, and slower progression of retinopathy than in intensively managed patients with no insulin secretory capacity.
Intensive team management of type 1 diabetic patients with no retinopathy, with a therapeutic goal of normoglycemia, results in 76% reduction in the risk for the development of clinically significant retinopathy compared with conventional management. A beneficial effect on retinopathy progression is maintained for least 4 years after a prolonged period (mean: 6.5 years) of intensive management.
Significant effects of intensive management include a decrease urinary albumin excretion (an index of nephropathy) and a reduction in clinical evidence of peripheral sensory and autonomic neuropathy.
Favorable trends occur in macrovascular endpoints with intensive management of type 1 diabetes.
Intensive management improves outcomes of pregnancy in type diabetes.
Although transient increases in retinopathy progression occur during pregnancy and in some patients with intensive management. the long-term risk of progression of retinopathy is not affected.
Increased ophthalmologic surveillance during pregnancy in type diabetes is indicated.
The two main adverse effects of intensive management of type diabetes are weight gain and an increased incidence of severe hypoglycemia.
Intensive treatment methods of type 1 diabetes have been under study since the completion of the DCCT with goals of decreasing the risks of excessive weight gain and severe hypoglycemia
Long-term follow-up of the DCCT cohort in the EDIC Trial will provide valuable natural history data and information on the effects of a defined period of intensive glycemic management on microvascular and macrovascular complications.