Skip to content

Diabetes Health Center

Font Size

Diabetes Control and Complications Trial (DCCT)

What Is the DCCT?

The DCCT is a clinical study conducted from 1983 to 1993 by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). The study showed that keeping blood sugar levels as close to normal as possible slows the onset and progression of eye, kidney, and nerve diseases caused by diabetes. In fact, it demonstrated that any sustained lowering of blood sugar helps, even if the person has a history of poor control.

The largest, most comprehensive diabetes study ever conducted, the DCCT involved 1,441 volunteers with type 1 diabetes and 29 medical centers in the United States and Canada. Volunteers had diabetes for at least 1 year but no longer than 15 years. They also were required to have no, or only early signs of, diabetic eye disease.

Recommended Related to Diabetes

Diabetes and Organ Transplant

In some cases, diabetes can lead to damage that makes an organ transplant necessary. But diabetes isn't only a reason for organ transplants. It can also be the result. Experts are not certain just how often people develop type 2 diabetes after the transplant of a heart, liver, kidney, lung, or other organ. One review of studies suggested that it could occur in more than one out of 10 people who get a transplant. Diabetes is always a serious illness. But it can have greater risks in people who have...

Read the Diabetes and Organ Transplant article > >

The study compared the effects of two treatment regimens--standard therapy and intensive control--on the complications of diabetes. Volunteers were randomly assigned to each treatment group.

DCCT Study Findings

Lowering blood sugar reduces risk:

  • Eye disease
    76% reduced risk
  • Kidney disease
    50% reduced risk
  • Nerve disease
    60% reduced risk

How Did Intensive Treatment Affect Diabetic Eye Disease?

All DCCT participants were monitored for diabetic retinopathy, an eye disease that affects the retina. Study results showed that intensive therapy reduced the risk for developing retinopathy by 76 percent. In participants with some eye damage at the beginning of the study, intensive management slowed the progression of the disease by 54 percent.

The retina is the light sensing tissue at the back of the eye. According to the National Eye Institute, one of the National Institutes of Health, as many as 24,000 persons with diabetes lose their sight each year. In the United States, diabetic retinopathy is the leading cause of blindness in adults under age 65.

How Did Intensive Treatment Affect Diabetic Kidney Disease?

Participants in the DCCT were tested to assess the development of diabetic kidney disease (nephropathy). Findings showed that intensive treatment prevented the development and slowed the progression of diabetic kidney disease by 50 percent.

Diabetic kidney disease is the most common cause of kidney failure in the United States and the greatest threat to life in adults with type 1 diabetes. After having diabetes for 15 years, one-third of people with type 1 diabetes develop kidney disease. Diabetes damages the small blood vessels in the kidneys, impairing their ability to filter impurities from blood for excretion in the urine. Persons with kidney damage must have a kidney transplant or rely on dialysis to cleanse their blood.

How Did Intensive Treatment Affect Diabetic Nerve Disease?

Participants in the DCCT were examined to detect the development of nerve damage (diabetic neuropathy). Study results showed the risk of nerve damage was reduced by 60 percent in persons on intensive treatment.

Diabetic nerve disease can cause pain and loss of feeling in the feet, legs, and fingertips. It can also affect the parts of the nervous system that control blood pressure, heart rate, digestion, and sexual function. Neuropathy is a major contributing factor in foot and leg amputations among people with diabetes.

Is This Normal? Get the Facts Fast!

Check Your Blood Sugar Level Now
What type of diabetes do you have?
Your gender:

Get the latest Diabetes newsletter delivered to your inbox!


or
Answer:
Low
0-69
Normal
70-130
High
131+

Your level is currently

If the level is below 70 or you are experiencing symptoms such as shaking, sweating or difficulty thinking, you will need to raise the number immediately. A quick solution is to eat a few pieces of hard candy or 1 tablespoon of sugar or honey. Recheck your numbers again in 15 minutes to see if the number has gone up. If not, repeat the steps above or call your doctor.

People who experience hypoglycemia several times in a week should call their health care provider. It's important to monitor your levels each day so you can make sure your numbers are within the range. If you are pregnant always consult with your health care provider.

Congratulations on taking steps to manage your health.

However, it's important to continue to track your numbers so that you can make lifestyle changes if needed. If you are pregnant always consult with your physician.

Your level is high if this reading was taken before eating. Aim for 70-130 before meals and less than 180 two hours after meals.

Even if your number is high, it's not too late for you to take control of your health and lower your blood sugar.

One of the first steps is to monitor your levels each day. If you are pregnant always consult with your physician.

Did You Know Your Lifestyle Choices
Affect Your Blood Sugar?

Use the Blood Glucose Tracker to monitor
how well you manage your blood sugar over time.

Get Started

This tool is not intended for women who are pregnant.

Start Over

Step:  of 

Today on WebMD

Diabetic tools
Symptoms, diagnosis, treatment, and more.
woman flexing muscles
10 strength training exercises.
 
Blood sugar test
12 practical tips.
Tom Hanks
Stars living with type 1 or type 2.
 
Woman serving fast food from window
Video
Can Vinegar Treat Diabetes
Video
 
Middle aged person
Tool
are battery operated toothbrushes really better
Video
 

Prediabetes How to Prevent Type 2 Diabetes
Article
type 2 diabetes
Slideshow
 
food fitness planner
Tool
Are You at Risk for Dupuytrens Contracture
Article