What are the most important factors in preventing diabetes complications?

prevention of diabetes complicationsGuest Post from David Mapletoft, Diabetes Educator

As a diabetes educator  I have never liked this term ‘complications’.

But no matter what you name it, loss of vision, heart disease, stroke, kidney failure, peripheral neuropathy, autonomic neuropathy etc all have dire effect on one’s quality of life (QOL)

Research studies including the Diabetes Control and Complications Trial (DCCT) have shown that control of blood glucose, blood pressure, and blood lipid levels helps prevent complications in people with type 1 or type 2 diabetes.

The Diabetes Control and Complications Trial (DCCT)

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

The DCCT involved 1,441 volunteers, ages 13 to 39, with type 1 diabetes and 29 medical centers in the United States and Canada. Volunteers had to have 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.

The study compared the effects of standard / conventional control (The conventional diabetes therapy group received one or two daily insulin injections) of blood glucose versus intensive control ( the intensive therapy group frequently monitored blood glucose levels and received at least three daily insulin injections; a few wore an external pump) on the complications of diabetes.

Intensive control meant keeping hemoglobin A1C levels as close as possible to the normal value of 6 percent or less. The A1C blood test reflects a person’s average blood glucose over the last 2 to 3 months. Volunteers were randomly assigned to each treatment group.

Control of blood glucose

Lowering blood glucose reduces risk:

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

In Australia the RACGP recommend a general target range of blood glucose levels to be:

  • Targets for SMBG levels are 6–8 mmol/L fasting and pre-prandial, and 6–10 mmol/L 2 h postprandial
  • and the general HbA1c target in people with type 2 diabetes is ≤7% (≤53 mmol/mol). Adjustments to diabetes treatment should be considered when HbA1c is above this level.”

The authors of the DCCT noted that they were unable to show any reduction in cardiovascular morbidity and mortality. This is important because people with diabetes are two to four times more likely to have heart disease than persons without diabetes, and 75% of all diabetes-related deaths are from cardiovascular disease.

A possible explanation for this is that the population studied in the DCCT was relatively young (the age range of participants was 13–39 years), and therefore their likelihood of having a significant cardiovascular event during the follow-up period was low.

However, it is still generally accepted that managing blood pressure and blood lipids (cholesterol and triglycerides) is important to help with cardiovascular health.

Cardiovascular disease:
  • is heart, stroke and blood vessel diseases
  • kills one Australian every 12 minutes
  • affects one in six Australians or 3.72 million
  • CVD was the main cause for 523,805 hospitalisations in 2011/12 and played a secondary role in a further 800,000
  • claimed the lives of 43,946 Australians (30% of all deaths) in 2012 – deaths that are largely preventable
  • lower socioeconomic groups, Aboriginal and Torres Strait Islander people and those living in remote areas had the highest rate of hospitalisation and death resulting from CVD in Australia.


From the RACGP guidelines for people living with type 2 diabetes

“Adults with any of the following conditions do not require absolute cardiovascular risk assessment using the Framingham Risk Equation because they are already known to be at clinically determined high risk of CVD:

  • Diabetes and age >60 years
  • Diabetes with microalbuminuria (>20 mcg/min or urinary albumin-to-creatinine ratio (UACR) >2.5 mg/mmol for men, >3.5 mg/mmol for women)
  • Moderate or severe CKD (CKD) (persistent proteinuria or eGFR <45 mL/min/1.73 m2)
  • A previous diagnosis of familial hypercholesterolaemia
  • SBP ≥180 mmHg or DBP ≥110 mmHg
  • Serum total cholesterol >7.5 mmol/L

Blood Pressure

Target: ≤130/80 mmHg in all people with diabetes


It is possible to have blood pressure high enough to be causing health problems – and you will feel no symptoms. Ideally, your health care professional will measure your BLOOD PRESSURE every visit or at least every 3 months.

Blood lipid levels

**HDL cholesterol, higher levels are better**

**Low HDL cholesterol puts you at higher risk for heart disease**

Total Cholesterol <4.0 mmol/L (Your total cholesterol score is calculated using the following equation: HDL + LDL + 20 percent of your triglyceride level. )

HDL-C ≥1.0 mmol/L (These lipoproteins are often referred to as HDL, or “good,” cholesterol. They act as cholesterol scavengers, picking up excess cholesterol in your blood and taking it back to your liver where it’s broken down. The higher your HDL level, the less “bad” cholesterol you’ll have in your blood.)

LDL-C  <2.0  (Low-density lipoprotein cholesterol (LDL-C) is widely recognized as an established cardiovascular risk marker predicated on results from numerous clinical trials that demonstrate the ability of LDL-C to independently predict development and progression of coronary heart disease) mmol/L;

Non-LDL-C <2.5 mmol/L (is simply the difference between the total cholesterol concentration and the HDL cholesterol concentration)

Triglyceride  <2.0 mmol/L. (A triglyceride is an ester derived from glycerol and three fatty acids. As a blood lipid, it helps enable the bidirectional transference of adipose fat and blood glucose from the liver)


  • Talk to your health care professionals about how often your measurements need to be taken and ask about treatment options for each test undertaken.
  • Ask questions (where you get an answer that you understand) of the health care professional that you are visiting.

Kind Regards,

David, Diabetes Educator