Oxidative markers in diabetic ketoacidosis

Oxidative stress has been implicated in the pathogenesis of the chronic com plications of diabetes mellitus but little is known in diabetic ketoacidosi s (DKA). The aim of this work was to determine whether lipid peroxidation, as assessed by measuring malondialdehyde (MDA, a prooxidant) and antioxidan t status (TAS, an index of antioxidant defenses), is modified in DKA, and a lso whether any observed abnormalities were related to metabolic disturbanc es. Methods: four groups of patients were studied, comprising 19 patients w ith DKA, massive ketonuria and plasma standard bicarbonate levels below 16 mmol/l (group 1); 20 patients with poorly controlled diabetes, glycated hem oglobin (HbA(1c) above 8% and plasma bicarbonate levels above 16 mmol/l (gr oup 2); 11 patients with well-controlled diabetes and HbA(1c) below 8% (gro up 3); and 10 nondiabetic, non-obese control subjects (group 4). Metabolic parameters, MDA levels and TAS were assessed in the plasma of the four grou ps of subjects. Results: mean plasma MDA and TAS values were significantly different among the four groups (respectively p<0.001 and p<0.01). Mean pla sma MDA value was significantly higher in group 1 than in group 3 (p<0.02) and group 4 (p<0.001) but was not different from that in group 2. Mean plas ma MDA value in group 2 was significantly lower than that in group 4 (p=0.0 02). Mean plasma TAS value in group 1 was significantly lower than in group s 3 (p<0.002) and 4 (p<0.05). Mean plasma TAS value was significantly lower in group 2 than in group 4 (p<0.05). Plasma MDA values in the diabetic pat ients (groups 1+2+3) were not related to any clinical characteristics (BMI, age, duration of the disease) or metabolic parameters (glycemia, HbA(1c), bicarbonates, blood urea nitrogen, phosphatemia, lipids), while plasma TAS values correlated negatively with glycemia, osmolality and HbA(1c). A signi ficant relationship was also found between TAS and HbA(1c) in group 1 (p<0. 05) and between MDA and HbA(1c) in group 3 (p<0.05). Correlations were also found between TAS and phosphatemia in group 1 (p<0.01) and between MDA and phosphatemia in group 2 (p<0.01). A positive relationship between MDA and cholesterol levels was found in group 1 (p<0.01). In conclusion, MDA values are increased and TAS values decreased in DKA and poorly controlled diabet es, and tend to correlate more with markers of diabetic imbalance than with markers of acute metabolic disturbances of DKA. (C) 2000, Editrice Kurtis.