Increased Serum Conjugated Dienes in Elderly Diabetic Patients

To determine if lipid peroxidation by-products are increased in the serum of elderly diabetic patients, serum concentrations of conjugated dienes were measured in 45 Type 2 diabetic men over the age of 60 years, and the results were compared to those of 24 age-matched healthy men. Patients with diabetic complications such as retinopathy, nephropathy, neuropathy, peripheral vascular disease, coronary or cerebrovascular disease, (n = 22) had significantly increased serum levels of conjugated dienes (0.4951 +/- 0.065 O.D./mL) compared to healthy controls (0.2368 +/- 0.028 O.D./mL) (P less than 0.01). The level of conjugated dienes in diabetic patients without complications (0.3854 +/- 0.0316 O.D./mL) was intermediate between the level found in control subjects and the level in patients with diabetic complications. The serum levels of conjugated dienes correlated best with serum triglyceride concentration (r = 0.51) and to a lesser extent with serum glucose concentration (r = 0.36). It is concluded that elderly patients with diabetes, especially those with complications, have increased serum levels of lipid peroxidation by-products. This can not be totally attributed to alterations in serum cholesterol, phospholipid, or triglyceride levels.