PLASMA LACTATE CONCENTRATION IN OBESITY AND TYPE-2 DIABETES

The purpose of this study was three-fold: 1) to define the effects of obesity and Type 2 diabetes on plasma lactate concentrations; 2) to re late changes in plasma lactate concentration to plasma glucose and ins ulin concentrations; and 3) to evaluate the effect of differences in b lood sample processing on plasma lactate determination in a disparate population group. To accomplish this, fasting plasma lactate concentra tions were determined in 30 volunteers (1O non-obese individuals with normal glucose tolerance, 10 obese individuals with normal glucose tol erance, and 10 obese individuals with Type 2 diabetes) on blood drawn, processed, and maintained in a variety of ways. Results demonstrated that fasting plasma lactate measurements were least confounded when bl ood was drawn without the subject << hand pumping >> following venous occlusion, the samples maintained on ice at 4 degrees C until precipit ated with perchloric acid, and kept as this temperature until lactate concentration was determined. Under these conditions, plasma lactate c oncentration was lowest in the non-obese group with normal glucose tol erance (0.81 +/- 0.07 mmol/L), highest in the obese subjects with Type 2 diabetes (1.46 +/- 0.14 mmol/L), and intermediate in obese individu als with normal glucose tolerance (1.17 +/- 0.13 mmol/L). All three gr oups were significantly different from each other. In addition plasma lactate concentrations were associated with both fasting plasma glucos e and glycated haemoglobin concentrations.