Plasma levels of lipophilic antioxidants in very old patients with type 2 diabetes

Background Experimental research indicates that oxidative stress is implica ted in aging and in the pathogenesis of diabetes and its complications. Thi s evidence is limited in elderly patients with non-insulin dependent diabet es, in which age- and disease-related production of reactive oxygen species might exert synergistic damaging effects on tissues and organs. Methods Plasma levels of lipid-soluble compounds with antioxidant propertie s including vitamin A, vitamin E and carotenoids (lutein, zeaxanthin, beta- cryptoxanthin, lycopene, alpha- and beta-carotene) were measured by HPLC in 72 elderly patients with non-insulin dependent diabetes (75.7+/-0.8 years, 40 F, 32 M) and in 75 age-matched controls (77.2+/-1.2 years, 48 F, 27 M). Results All compounds measured were significantly lower in plasma from diab etic patients as compared to controls (p<0.0001). Plasma levels of vitamins A and E and of carotenoids did not significantly correlate with dietary in take and lipid profile in both groups. In patients, significant inverse cor relations were found between age and levels of vitamin E, beta-cryptoxanthi n, lycopene and beta-carotene. Conclusions We conclude that patients of very old age with Type 2 diabetes show a poor plasma status of vitamins A and E and carotenoids, which negati vely correlates with age. Further studies are needed to explore the possibl e therapeutic role of lipid-soluble vitamin supplements in elderly diabetic subjects. Copyright (C) 2000 John Wiley & Sons, Ltd.