Correcting lipid abnormalities in patients with type 2 diabetes can slow progression of coronary artery disease, a new study has shown.
The Diabetes Atherosclerosis Intervention Study (DAIS) found that treatment with fenofibrate led to up to 40 per cent reduction in progression of atherosclerosis.
Reporting the final results of the study on June 26, Professor George Steiner (professor of medicine, University of Toronto) said that while sub-group analysis of diabetic patients in previous lipid lowering trials had shown benefit from treatment, DAIS was the first study specifically set up to assess the effects of treatment of lipid abnormalities in diabetes.
The study was carried out in collaboration with the World Health Organisation. It involved 418 patients with good glycaemic control. Their pattern of lipid abnormalities were typical of those found in diabetes (moderately raised triglycerides, moderately low high density lipoprotein [HDL] and normal to mildly raised low density lipoprotein [LDL]).
At entry all patients had at least one angiographically detectable stenosis. Around 50 per cent of patients had a history of coronary artery disease. Patients received micronised fenofibrate (200mg/day) or placebo, and follow up lasted a mean of 38 months.
Atherosclerosis progression was measured by angiography. Professor Steiner said that treatment reduced progression of focal lesions (which were thought to be representative of unstable atherosclerotic plaque) by 40 per cent (statistically significant) and there was a 25 per cent reduction (not significant) in diffuse atherosclerosis.
The trial was not powered to assess clinical end points - it was too small and too short - but he reported that there was a non-significant 23 per cent reduction in combined clinical coronary end points (death, myocardial infarction, need for angioplasty or bypass surgery). Benefit was seen in both men and women.
Emphasising that patients with diabetes had a two to four fold increased incidence of coronary disease, Professor Steiner said that the DAIS results highlighted the need to correct even minor lipid abnormalities in diabetes. "The lipid profile seen at trial entry would often be considered to be normal and many physicians would not consider treatment," he said. "Diabetologists have up to now not been much concerned about lipids, but we must be more aggressive in treating lipid abnormalities in patients with diabetes."
If lifestyle measures did not normalise the lipid profile, drug treatment was necessary, he said.
At a press conference held by Fournier after Professor Steiner's presentation to the symposium, Professor Philip Barter (professor of cardiology, University of Adelaide) described the DAIS results as "stunning". They added to those of last year's VA-HIT study (which involved a different population group) in showing the importance of low HDL as an independent risk factor for coronary heart disease. He suggested that the DAIS results indicated that HDL was "as important as, or more important than, LDL." Lipid lowering medication should be tailored to the individual's lipid disorder, he said. If LDL was high, statins were the tried and tested treatment, but if LDL was low, and HDL was low, then evidence for statins was "not so strong" while that for fibrates was increasing.
DAIS used angiography as a surrogate marker for clinical events. Professor Barter added that a new 9,000-patient fenofibrate trial was now under way to assess clinical outcomes in patients with diabetes. Results would not be available for four years.