Impact of Nonalcoholic Fatty Liver Disease on Insulin... : Official journal of the American College of Gastroenterology | ACG (original) (raw)

ORIGINAL CONTRIBUTIONS: LIVER

Impact of Nonalcoholic Fatty Liver Disease on Insulin Resistance in Relation to HbA1c Levels in Nondiabetic Subjects

Bae, Ji Cheol MD1; Cho, Yong Kyun MD, PhD2,4; Lee, Won Young MD, PhD1,4; Seo, Hyun Il MD2; Rhee, Eun Jung MD, PhD1; Park, Se Eun MD1; Park, Cheol Young MD, PhD1; Oh, Ki Won MD, PhD1; Sung, Ki Chul MD, PhD3; Kim, Byung Ik MD, PhD2

1Division of Endocrinology and Metabolism, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea

2Division of Gastroenterology and Hepatology, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea

3Division of Cardiology, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea

4These authors contributed equally to this work

Correspondence: Yong Kyun Cho, MD, PhD, Division of Gastroenterology and Hepatology, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul 110-746, Korea. E-mail: [email protected]

Won Young Lee, MD, PhD, Division of Endocrinology and Metabolism, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul 110-746, Korea. Email: [email protected]

published online 13 July 2010

Received 18 February 2010; accepted 25 May 2010

Abstract

OBJECTIVES:

A cross-sectional analysis was conducted in healthy, nondiabetic Korean adults to assess the prevalence of nonalcoholic fatty liver disease (NAFLD), to compare the prevalence of NAFLD across different glycemic ranges as assessed by glycosylated hemoglobin (HbA1c), and to examine the impact of NAFLD on insulin resistance in relation to HbA1c levels.

METHODS:

After rigorous exclusion criteria, the final number of subjects who participated in a comprehensive health status checkup program was 99,969. All subjects were classified into four categories with respect to HbA1c level (≤4.9, 5.0–5.4, 5.5–5.9, and 6.0–6.4%). We estimated the odds ratio (OR) for prevalence of NAFLD according to the categorized level of HbA1C and evaluated the association of NAFLD with the homeostatic model assessment of insulin resistance (HOMA-IR) in relation to the HbA1c level.

RESULTS:

Twenty-eight percent ( n =28,130, 40.2% of the men, 10.3% of the women) of the study subjects had NAFLD. Men had a 5.83-fold (95% confidence interval 5.63–6.05) increased risk for having NAFLD than did women. The risk for NAFLD increased with increasing level of HbA1c (OR 1.44, 2.62, and 7.18) when compared with the lowest quartile (HbA1C≤4.9%). HOMA-IR increased in the NAFLD subjects as the level of HbA1c increased. The magnitude of association of HOMA-IR with HbA1c level was greater in NAFLD subjects than in non-NAFLD subjects ( P <0.001 for interaction). These associations were consistent even after adjustment for body mass index and other metabolic components.

CONCLUSIONS:

NAFLD had an association with HbA1c level and insulin resistance in nondiabetic individuals, and these associations were independent of obesity and other metabolic components.