AIM: To determine the association of diabetes mellitus (DM) and international normalized ratio (INR) level in hepatocellular carcinoma (HCC) patients. METHODS: Our present study included 375 HCC patients who were treated at the China-Japan Friendship Hospital, Ministry of Health (Beijing, China), in the period from January 2003 to April 2012, and with a hospital discharge diagnosis of HCC. The demographic, clinical, laboratory, metabolic and instrumental features were analyzed. chi(2) test, Student's t test and Mann-Whitney U test were used to compare the differences between HCC patients with and without DM. Unconditional multivariable logistic regression analysis was used to determine the association of DM and INR level in HCC patients. A sub-group analysis was performed to assess the effect of liver cirrhosis or hepatitis B virus (HBV) infection on the results. The Pearson correlation test was used to determine the relationship between INR level and fasting glucose. In addition, association between diabetes duration, and diabetes treatment and INR level was determined considering the potentially different effects. RESULTS: Of the total, 63 (16.8%) patients were diabetic (diabetic group) and 312 (83.2%) patients were diagnosed without diabetes (non-diabetic group). Their mean age was 56.4 +/- 11.0 years and 312 (83.2%) patients were male. Compared with patients without DM, the HCC patients with diabetes were older (59.5 +/- 10.3 vs 55.8 +/- 11.1, P = 0.015), had a lower incidence of HBV infection (79.4% vs 89.1%, P = 0.033), had increased levels of systolic blood pressure (SBP) (133 +/- 17 vs 129 +/- 16 mmHg, P = 0.048) and INR (1.31 +/- 0.44 vs 1.18 +/- 0.21, P = 0.001), had lower values of hemoglobin (124.4 +/- 23.9 vs 134.2 +/- 23.4, P = 0.003) and had a platelet count (median/interquartile-range: 113/64-157 vs 139/89-192, P = 0.020). There was no statistically significant difference in the percentages of males, overweight or obesity, drinking, smoking, cirrhosis and Child classification. After controlling for the confounding effects of age, systolic blood pressure, hemoglobin, platelet count and HBV infection by logistic analyses, INR was shown as an independent variable [odds ratio (OR) = 3.650; 95% CI: 1.372-9.714, P = 0.010]. Considering the effect of liver cirrhosis on results, a sub-group analysis was performed and the study population was restricted to those patients with cirrhosis. Univariate analysis showed that diabetic patients had a higher INR than non-diabetic patients (1.43 +/- 0.51 vs 1.25 +/- 0.23, P = 0.041). After controlling for confounding effect of age, SBP, hemoglobin, platelet count and HBV infection by logistic analyses, INR level remained as the sole independent variable (OR = 5.161; 95% CI: 1.618-16.455, P = 0.006). No significant difference in the relationship between INR level and fasting glucose was shown by Pearson test (r = 0.070, P = 0.184). Among the 63 diabetic patients, 35 (55.6%) patients had been diagnosed with DM for more than 5 years, 23 (36.5%) received oral anti-diabetic regimens, 11 (17.5%) received insulin, and 30 (47.6%) reported relying on diet alone to control serum glucose levels. No significant differences were found for the association between DM duration/treatment and INR level, except for the age at diabetes diagnosis. CONCLUSION: The INR level was increased in HCC patients with DM and these patients should be monitored for the coagulation function in clinical practice. (C) 2013 Baishideng. All rights reserved.