NEW YORK — Three lipid measures were strong predictors of the future risk of type 2 diabetes in a study of 362 patients who were assessed prior to undergoing coronary angiography.
High serum levels of triglycerides, low levels of HDL cholesterol, and a small size of LDL cholesterol particles all identified patients who had an increased risk of developing type 2 diabetes during 4 years of follow-up, Christoph H. Saely, M.D., reported at an international symposium on triglycerides and HDL.
Because of this link with a bad clinical outcome, these lipid markers may be useful for identifying patients who stand to gain the most from lifestyle modifications, said Dr. Saely, a physician at the Vorarlberg Institute for Vascular Intervention and Treatment in Feldkirch, Austria. The lipid markers may also be able to flag patients who warrant frequent surveillance of their glucose tolerance.
The study involved patients without diabetes who were scheduled for coronary angiography because of suspected coronary artery disease. At baseline, 172 of the patients had a normal fasting glucose level of less than 100 mg/dL; the remaining 190 patients had impaired fasting glucose, defined as a level of at least 100 mg/dL.
During 4 years of follow-up, incident type 2 diabetes was diagnosed in 15 patients. Thirteen of these cases had impaired fasting glucose at baseline. In a multivariate analysis, patients with impaired fasting glucose had a 5.5-fold increased risk of developing type 2 diabetes compared with those who had normal fasting glucose levels.
An additional multivariate analysis showed that patients who had an elevated level of serum triglycerides at baseline had a 2.5-fold increased risk of developing type 2 diabetes, compared with those who did not have elevated triglycerides. Patients with a low level of HDL cholesterol at baseline also had a 2.5-fold increased risk of developing type 2 diabetes, and patients with a high level of small, dense LDL particles also had a 2.5-fold higher risk of developing type 2 diabetes.
All three analyses evaluated these lipid measures as continuous variables. As a result, the study was unable to identify a particular cutoff value that defined high triglyceride level, low HDL cholesterol level, or a high level of small LDL particles, Dr. Saely said at the symposium, sponsored by the Giovanni Lorenzini Medical Foundation.
These lipid measures probably flag patients at high risk of developing type 2 diabetes because they identify patients who either have or soon develop metabolic syndrome, Dr. Saely told this newspaper. But he cautioned that the epidemiologic relationships seen in this study can only be applied with confidence to similar groups of patients: those who are suspected of having coronary artery disease and are scheduled to undergo coronary angiography.