Treatment for Juvenile Diabetes
When blood glucose is chronically too high, as it is in untreated juvenile (type 1) diabetes, serious complications can arise. These include retinopathy (disease of the retina of the eye), nephropathy (kidney disease), neuropathy (disease of the peripheral nerves), and cardiovascular disease. The complications can lead to blindness, kidney failure, amputation of the extremities, heart attack, stroke, and death. Thanks to several landmark studies, researchers have shown that juvenile diabetes treatment effectively prevents diabetes complications.
The Diabetes Control and Complications Trial
The Diabetes Control and Complications Trial (DCCT) was conducted from 1983 to 1993 in 29 medical centers located throughout the United States and Canada. Study participants all had juvenile diabetes and were each followed for an average of seven years. The volunteers were divided into two experimental groups. The conventional treatment group was treated with the goal of achieving "clinical well-being," while the intensive treatment group was treated with the goal of lowering blood sugar to normal levels. The glycosylated hemoglobin level (A1C test) was used to track blood glucose over time in the participants.
The clinicians were not able to meet their official goal in the intensive treatment group; the average A1C value was about 40% higher than the normal value of about 6%, even with intensive treatment. Yet this group did reach another important achievement: their risk of retinopathy, nephropathy, and neuropathy was about 60% lower than in the conventional treatment group.
The Epidemiology of Diabetes Interventions and Complications Study
The Epidemiology of Diabetes Interventions and Complications (EDIC) study is a follow-up to the DCCT that tracked 94% of the original study participants. The goals of EDIC were to determine how intensive versus conventional treatment affected risk of cardiovascular disease (which takes to long to develop to have been tracked by the DCCT) and what long-term benefits, if any, may exist for the intensive treatment group in regard to other complications.
So far, EDIC has found that intensive therapy reduces the risk of any type of cardiovascular disease in type 1 diabetics by 42%. The risk of heart attack, stroke, and death from cardiovascular disease was reduced by 57%. The risk of retinopathy, nephropathy, and neuropathy, including advanced disease that takes too long to develop to have been tracked by the DCCT, continued to be lower in the intensive treatment group than in the conventional treatment group. In fact, the study found that early juvenile diabetes treatment had a protective effect later in the patient’s life, even if the intensive treatment was discontinued; this phenomenon is called "metabolic memory."
What Do the Results Mean for Juvenile Diabetes Treatment?
The conclusion reached by the researchers is that juvenile diabetes treatment should aim to keep blood glucose as close to normal as possible in order to avoid diabetes complications. This intensive therapy is most effective when started early because of the effect of metabolic memory. Reaching the A1C results typical of the intensive treatment group means either the use of an insulin pump or a minimum of three insulin injections daily.
Intensive therapy is not risk-free, however; it increases the patient’s risk of hypoglycemia. Severe hypoglycemia causes acute symptoms and, in rare cases, even death, but the DCCT and EDIC studies found that it does not have long-term effects once the patient recovers. Thus, the benefits of intensive therapy outweigh the risks.
- "DCCT and EDIC: The Diabetes Control and Complications Trial and Follow-up Study." National Diabetes Information Clearinghouse, 2008. Available at https://diabetes.niddk.nih.gov/dm/pubs/control/
- "Implications of the Diabetes Control and Complications Trial." Diabetes Care 26:S25-S27, 2003 (American Diabetes Association). Available at https://care.diabetesjournals.org/cgi/content/full/26/suppl_1/s25
- "Summary of the DCCT/EDIC Study." National Institute of Diabetes and Digestive and Kidney Diseases Repository, 2005. Available as PDF at https://www.niddkrepository.org/niddkdocs/EDIC/EDIC_Summary_for_RTI_full.pdf