Significance of oral glucose tolerance tests in non-alcoholic fatty liver disease patients with a fasting plasma glucose level of <126 mg/dL and HbA1c level of ≤ 6.4% in Japan.

Abstract

OBJECTIVE:

The aim of this study was to clarify the indications for oral glucose tolerance tests (OGTT) in non-alcoholic fatty liver disease (NAFLD) subjects with a HbA1c level of ≤6.4%, fasting plasma glucose (FPG) level of <126 mg/dL and no history of diabetes.

PATIENTS:

A total of 569 NAFLD subjects underwent 75-g OGTT. The plasma glucose and insulin levels were analyzed periodically for three hours during the OGTT examinations. Impaired fasting glucose (IFG) was defined as a plasma glucose level of ≥100 mg/dL to <126 mg/dL. Diabetes was defined as a two-hour post-load plasma glucose level of ≥200 mg/dL. Elevated insulin resistance was defined as a homeostasis model assessment-insulin resistance (HOMA-IR) of ≥2.5. Insulin secretory insufficiency was defined as an insulinogenic index of <0.4.

RESULTS:

The prevalence of diabetes on the OGTT was 7.7% (44/569) among the NAFLD patients with an HbA1c level of ≤6.4%, FPG level of <126 mg/dL and no history of diabetes. A multivariate analysis showed that diabetes occurred more frequently when the subjects had IFG [odds ratio (OR) 5.13; 95% confidential interval (CI) 3.01-8.76; p<0.001] and an HbA1c level of 5.7-6.4% (OR 5.45; 95% CI 3.33-8.93; p<0.001). Of the NAFLD subjects with both IFG and an HbA1c level of 5.7-6.4%, 22.8% (28/123) exhibited a pattern of diabetes on OGTT. Regarding insulin dynamics, among the NAFLD subjects with both IFG and an HbA1c level of 5.7-6.4%, 25.2% (31/123) had elevated IR alone, 25.2% (31/123) had insulin secretory deficiency alone and 27.6% (34/123) had both elevated insulin resistance and insulin secretory deficiency.

CONCLUSION:

NAFLD subjects with IFG and an HbA1c level of 5.7-6.4% should undergo OGTT in order to determine whether they have diabetes and/or abnormal insulin dynamics.

• Authors: Naoki Matsumoto, Yasuji Arase, Yusuke Kawamura, Miki Ohmoto-Sekine, Kazuhisa Amakawa, Kyoko Ogawa, Hiroshi Tsuji, Hsieh Shiun Dong, Shigeko Hara, Norio Akuta, Fumitaka Suzuki, Yoshiyuki Suzuki, Kenji Ikeda, Hiromitsu Kumada, Tetsurou Kobayashi
• Journal: Internal medicine (Tokyo, Japan) (Intern Med) Vol. 54 Issue 8 Pg. 875-80 ( 2015) ISSN: 1349-7235 [Electronic] Japan
• PMID: 25876566 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Blood Glucose
• Glycated Hemoglobin A
• Insulin

Topics

• Aged
• Asian People
• Blood Glucose
• Diabetes Mellitus (blood, diagnosis)
• Fasting (blood)
• Female
• Glucose Tolerance Test
• Glycated Hemoglobin
• Humans
• Insulin (metabolism)
• Insulin Resistance (physiology)
• Japan (epidemiology)
• Male
• Middle Aged
• Non-alcoholic Fatty Liver Disease (blood)
• Prediabetic State (diagnosis)
• Prevalence