Impact of glucose load in an oral glucose tolerance test on urinary albumin excretion varies with 2-h glucose levels.

Abstract

BACKGROUND:

The aim of the present study was to investigate whether an oral glucose load can induce an increase in urinary albumin excretion (UAE).

METHODS:

One hundred and thirty subjects without macroalbuminuria or increased fasting serum glucose (≥7.0 mmol/L) were included in the study. At 0600 hours, subjects were asked to empty their bladder and drink 300 mL water. At 0800 hours, venous blood and 2-h urine were collected for fasting examination. Subjects were then asked to drink 300 mL solution containing 75 g glucose and, at 1000 hours, samples were collected again for post-challenge examination. Concentrations of serum glucose, urinary glucose, albumin, N-acetyl-β-D-glucosaminidase and retinol-binding protein were measured.

RESULTS:

Based on the results of the oral glucose tolerance test, subjects were divided into three groups: (i) normal glucose tolerance (NGT; n = 55); (ii) impaired glucose tolerance (IGT; n = 39); and (iii) newly diagnosed diabetes mellitus (NDM; n = 36). In the NDM group, post-challenge urinary excretion of glucose and albumin was 14- and 1.6-fold greater than fasting values, respectively. In the IGT and NGT groups, although post-challenge urinary glucose excretion was 2.6- and 1.6-fold greater than fasting values, UAE did not increase. There was a positive correlation between post-challenge serum glucose and the UAE rate (UAER; r = 0.24, P < 0.01) and the UAER increment (ΔUAER; r = 0.19, P < 0.05), as well as between the serum glucose increment and post-challenge UAER (r = 0.23, P < 0.01) and ΔUAER (r = 0.18, P < 0.05). Post-challenge serum glucose levels were independently correlated with logarithmically converted post-challenge UAER (β = 0.322, P = 0.008).

CONCLUSIONS:

Oral glucose load can induce a significant increase in UAE in NDM subjects. The main mechanism may be glomerular hyperfiltration.

• Authors: Sisi Chen, Kui Hong, Fang Zou, Qiang Peng, Weitong Hu, Juxiang Li, Xiaoyang Lai, Xiaoshu Cheng, Hai Su
• Journal: Journal of diabetes (J Diabetes) Vol. 8 Issue 2 Pg. 206-13 (Mar 2016) ISSN: 1753-0407 [Electronic] Australia
• PMID: 25676539 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2015 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd.

Chemical References

• Blood Glucose
• Glucose

Topics

• Administration, Oral
• Adult
• Aged
• Albuminuria (urine)
• Blood Glucose (metabolism)
• Fasting (blood, urine)
• Female
• Glucose (administration & dosage, metabolism)
• Glucose Tolerance Test (methods)
• Humans
• Male
• Middle Aged
• Multivariate Analysis
• Regression Analysis
• Time Factors