Association of plasma creatinine with lactic acid level in type 2 diabetic patients with normal renal function

Abstract

Objective To study the relationship between plasma creatinine and lactic acid levels in type 2 diabetic patients with normal renal function, and the effect of mefformiu administration on plasma lactic acid. Methods Blood samples were collected from 723 type 2 diabetic inpatients(275 cases treated with mefformin as treatment group and 448 without mefformin as control group). Plasma lactic acid was measured with enzyme-electrode assay. The fasting plasma glucose, fasting insulin, creatinine (Cr) , alanine aminotransferase (ALT), and HbA1C levels were also determined. Results (1) The lactic acid level in treatment group was significantly higher than that in control group [(1.33±0.57 vs 1.17±0.47) mmol/L, P<0.01] and so was the incidence of hyperlactacidemia (9.45% vs 4.91%, P<0.01). No lactic acidosis was found in all patients. (2) The correlation analysis showed that Cr, blood urea nitrogen, ALT and body mass index (BMI) were positively correlated with lactic acid in control group, and the positive correlation between Cr and lactic acid still existed (r= 0.345, P<0.01) after adjustment for ALT and BMI. (3) After being divided by 20 μmol/L Cr in control group, lactic acid levels in subgroup increased with the Cr levels, especially when Cr was over 90 μmol/L. The Cr cutpoint for predicting lactatemia was 95.35 μmol/L. Conclusion It is safe to administrate metformin in type 2 diabetic patients with normal renal function, along with low risk of lactic acidemia. The incidence of lactic acidemia may increase when plasma Cr level reaches 95.35 μmol/L, Key words: Diabetes mellitus; Lactic acid; Creatinine; Metformin