Potential role of diabetes mellitus in the progression of cirrhosis to hepatocellular carcinoma: a cross-sectional case-control study from Chinese patients with HBV infection
 
Chun Gao, Long Fang, Hong-Chuan Zhao, Jing-Tao Li and Shu-Kun Yao
Beijing, China
 
 
Author Affiliations: Department of Gastroenterology, China-Japan Friendship Hospital, Ministry of Health, Beijing 100029, China (Gao C, Fang L, Zhao HC, Li JT and Yao SK)
Corresponding Author: Shu-Kun Yao, MD, Department of Gastroenterology, China-Japan Friendship Hospital, Ministry of Health, No. 2 Yinghua East Road, Beijing 100029, China (Tel: 86-10-84206160; Fax: 86-10-64222978; Email: yaosk@zryhyy.com.cn)
 
© 2013, Hepatobiliary Pancreat Dis Int. All rights reserved.
doi: 10.1016/S1499-3872(13)60060-0
 
 
Contributors: GC conceived the study and wrote the first draft. GC, FL and LJT collected and analyzed the data. ZHC and YSK made critical revision of manuscript. All authors contributed to the design and interpretation of the study and to further drafts. GC is the guarantor.
Funding: The study was supported by grants from the National Natural Science Foundation of China (No. 30772859) and the Research Fund of the China-Japan Friendship Hospital, Ministry of Health (No. 2010-QN-01).
Ethical approval: The study was approved by the Human Research Ethics Committee of the hospital.
Competing interest: No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article.
 
 
BACKGROUND: Diabetes mellitus (DM) is regarded as a new risk factor for hepatocellular carcinoma (HCC), but few studies have focused on the potential role of DM in the progression of cirrhosis to HCC as well as in patients with simple HBV infection.
 
METHODS: A cohort of 1028 patients, treated at our hospital and with a hospital discharge diagnosis of HCC and/or cirrhosis, was screened. Among them, 558 were diagnosed with chronic HBV infection and 370 were analyzed statistically according to the diagnostic, inclusion and exclusion criteria. The demographic, clinical, metabolic, virological, biochemical, radiological and pathological features were analyzed and the multivariate logistic regression model was used to determine the potential role of DM.
 
RESULTS: In 248 cirrhotic patients, 76 were diabetic and their mean duration of DM was 4.6 years. In 122 HCC patients with cirrhosis, 25 were diabetic and their mean duration of DM was 4.4 years. Univariate analysis showed that compared with cirrhotic patients, the HCC patients had a higher percentage in males (P=0.001), a lower percentage in DM patients (P=0.039), a higher percentage in cigarette smokers (P=0.005), a higher percentage in patients with AFP>400 ng/mL (P<0.001), higher values of white blood cells (P<0.001), hemoglobin (P<0.001) and platelet (P<0.001), increased levels of ALT (P<0.001) and GGT (P<0.001), higher total bilirubin (P=0.018) and albumin levels (P<0.001), and a lower international normalized ratio (P<0.001). Multivariate logistic regression analysis showed that DM was an independent associated factor for HCC [odds ratio (OR)=0.376; 95% CI, 0.175-0.807; P=0.012]. Even after the HCC patients were restricted to those with decompensated cirrhosis and compared with decompensated cirrhotic patients, the similar result was observed (OR=0.192; 95% CI, 0.054-0.679; P=0.010).
 
CONCLUSIONS: DM is an independent factor in the progression of cirrhosis to HCC, but the role may be contrary to our current viewpoint. To clarify the causal relationship of DM and HCC, prospective and experimental studies are required.
 
(Hepatobiliary Pancreat Dis Int 2013;12:385-393)
 
KEY WORDS: diabetes mellitus; hepatocellular carcinoma; cirrhosis; chronic hepatitis B
 
 
Introduction
H
epatocellular carcinoma (HCC) is a common malignancy worldwide, and the incidence rate is increasing over the past two decades in China as well as in the United States, Japan and other countries.[1-3] Hepatitis virus, especially HCV, or alcoholic liver disease, has been confirmed to play important roles in more than 50% of this increase;[2,4] however, the reason has not yet been explained clearly. In 15%-50% of HCC patients no specific risk factor or reason has been found,[4-6] although some risk factors have been identified, including HBV, HCV, liver cirrhosis, heavy alcohol consumption, increasing age, male gender, non-alcoholic steatohepatitis (NASH), alfatoxin exposure, and positive family history.
 
Diabetes mellitus (DM) has been regarded as a potentially new risk factor for HCC[4,5,7-10] although a few earlier epidemiologic studies found no relationship between HCC and DM.[11, 12] In the Swedish cohort study,[9] patients with DM were at increased risk of developing primary liver cancer, which was supported by the two subsequent cohort studies conducted in Taiwan province of China and the USA.[5, 10]
 
The impact of DM on the development of HCC in HCV- or alcohol-related cirrhosis have been conducted.[13-16] They concluded DM is an independent risk factor for HCC in cirrhosis,[14,16] while no association was demonstrated in another two studies.[13, 15] No consensus has been reached about the role of DM in these studies. In addition, the four studies were conducted in the Netherlands, Italy and Japan, which could not been regarded as the representatives of the general population. Moreover, no information was available in patients with HBV-related cirrhosis. Our study was designed to determine the potential role of DM in the progression of cirrhosis to HCC in Chinese patients with simple HBV infection.
 
 
Methods
Study population
A cohort of 1028 patients (including 482 HCC and 546 cirrhotic patients) who were treated at our hospital from January 2003 to June 2009, and with a hospital discharge diagnosis of HCC and/or cirrhosis, were screened. Chronic HBV infection was defined as serum HBsAg-positive for at least six months or at diagnosis of HCC and/or cirrhosis. Patients who followed these criteria would be excluded: 1) those who had been treated by any method at inclusion or with confirmed diagnosis of HCC for more than 15 days; 2) those who had a confirmed HCV, HDV or HIV infection; 3)those who had heavy alcohol consumption >80 g/d in male or >40 g/d in female for more than 10 years; 4) those who had a confirmed diagnosis of drug- or poison-induced liver damage, including a confirmed exposure to aspergillus flavus; 5) those who had a presence of other malignancies, including leukemia and lymphoma; 6) those who were non-Chinese; and 7) those who had a presence of autoimmune hepatitis, schistosomiasis, primary biliary cirrhosis, Budd-Chiari syndrome, primary sclerosing cholangitis, hemachromatosis, Wilson's disease, rheumatic diseases or allergic disorder. The study was approved by the Human Research Ethics Committee of the hospital and it was in accordance with the principles of the Declaration of Helsinki.
 
Subject determinations
Liver cirrhosis was histologically diagnosed by needle biopsy or surgical specimens, or based on typical radiological features shown by at least two image examinations including ultrasound (US), contrast-enhanced dynamic computed tomography (CT) and magnetic resonance imaging (MRI), or by a single image technique associated with typical manifestations of decompensated liver function and portal hypertension.[6] HCC diagnosis was based on the histological findings of needle biopsy/surgery, or typical radiological features shown by at least two image examinations including US, CT, MRI and hepatic angiography or by a single positive imaging with a serum AFP level >400 ng/mL.[17] DM was characterized by fasting plasma glucose of 126 mg/dL or greater on at least two occasions, plasma glucose of 200 mg/dL or greater at 2-hour oral glucose tolerance test, or the need for oral hypoglycemic drug or insulin to control glucose.
 
Clinical and laboratory parameters
The demographic, metabolic, virological, biochemical, radiological and pathological features of the patients with HCC were recorded. The data were obtained at the diagnosis of HCC, but excluded those obtained on 15 days before or after the diagnosis. For the cirrhotic patients in our hospital, the first detected or measured value was regarded as the recorded value. Patients who have missing values which may affect statistical results would be excluded from the final analysis. According to the Asian and Chinese criteria, overweight was defined as BMI≥23 kg/m2 and obesity BMI≥25 kg/m2. The diagnosis of hypertension was defined as systolic blood pressure (SBP) ≥140 mmHg and/or diastolic blood pressure (DBP) ≥90 mmHg, and mean artery pressure (MAP) was computed as 1/3 SBP plus 2/3 DBP. Total bilirubin, serum albumin, international normalized ratio, ascites and hepatic encephalopathy were used to calculate the Child-Turcotte-Pugh (CTP) score.
 
The findings of physical examinations and image techniques including US, CT, MRI and hepatic angiography were re-assessed carefully by at least two authors independently for clinical classification, clinical stage and TNM stage of HCC. We classified tumor stages according to the criteria recommended by the Anticancer Committee of China and the International Union Against Cancer. In clinical classification, massive HCC was defined with a diameter of ≥5 cm, nodular HCC with a diameter of <5 cm, and small HCC with a diameter of <3 cm for single or two nodules.
 
Statistical analysis
Statistical analysis was performed using SPSS version 14.0 for Windows (SPSS, Chicago, IL., USA). Chi-square test, Student's t test and Mann-Whitney U test were used to compare the differences between the HCC and the cirrhotic groups. The association of HCC with any factor, especially DM, was analyzed using multiple factor unconditional logistic regression. According to the results of univariate analysis, together with our current knowledge and the basic principles of logistic analysis, some variables with statistical differences in univariate analysis were included in the multivariate analysis. For example, serum albumin would be excluded because of the independence of variables if CTP score had been included. Stepwise multiple regression analysis (backward: Wald; entry: 0.05, removal: 0.10) was used. We expressed results as odds ratios (ORs) and 95% confidence intervals (CIs). P<0.05 was considered statistically significant, and all P values quoted were two-sided.
 
 
Results
Study population and baseline characteristics
A total of 1028 patients with a hospital discharge diagnosis of HCC and/or cirrhosis were admitted in our hospital, including 482 patients with HCC and 546 with cirrhosis. Among them, 558 were diagnosed with chronic HBV infection and 370 were included in the statistical analysis. In the 482 HCC patients, 360 were excluded (Fig.) because of HCC without cirrhosis (102), HCV infection (38), heavy alcohol consumption (15), cryptogenic conditions (non-HBV and non-HCV) (120), confirmed diagnosis of HCC for more than 15 days or being treated at inclusion (57), non-Chinese (6), confirmed drug- or poison-induced liver damage (3), lack of some data (15), and other reasons (4). Table 1 shows the demographic, clinical, laboratory, metabolic and instrumental features of the left 122 HCC patients with HBV infection and cirrhosis. Of these patients, 25 (20.5%) were diabetic, 67 (54.9%) had decompensated cirrhosis, and 103 (84.4%) had a history of HBV infection. Their mean age was 54.7±10.0 years and 106 patients (86.9%) were male. Fifty-four patients (60.7%, 54/89) were overweight or obese, and 33 (27.0%) had hypertension. The clinical classification, clinical stage and TNM stage of the patients are shown in Table 2.
 
In the 546 cirrhotic patients, 298 were excluded (Fig.) because of HCV infection (54), heavy alcohol consumption (25), cryptogenic conditions (non-HBV and non-HCV) (138), non-Chinese (16), confirmed drug- or poison-induced liver damage (7), presence of other malignancies (15), autoimmune hepatitis (7), primary biliary cirrhosis (9), lack of some data which influenced the statistical analysis (8), and other reasons (19). Table 1 shows the baseline characteristics of 248 cirrhotic patients. Of these patients, 76 (30.6%) were diabetic, 147 (59.3%) had decompensated cirrhosis, and 202 (81.5%) had a history of HBV infection. Their mean age was 52.8±11.3 years and 178 patients (71.8%) were male. One hundred and two patients (57.0%, 102/179) were overweight or obese, and 58 patients (23.4%) had hypertension.
 
Role of DM in HCC in the progression of cirrhosis to HCC
Of the 122 HCC patients with cirrhosis, 25 were diabetic and their mean duration of DM was 4.4±4.3 years. The mean duration of cirrhosis was 2.2±4.2 years and 43 patients had been diagnosed for more than one year before the diagnosis of HCC. Of the 248 cirrhotic patients, 76 were diabetic and their mean duration of DM was 4.6±6.2 years. The mean duration of cirrhosis was 2.4±4.1 years and 107 patients (43.1%) had been diagnosed for one year before entry. Univariate analysis (Table 1) showed that there were more diabetics in the cirrhotic group than in the HCC group (30.6% vs 20.5%, P=0.039), but no significant differences were observed in the duration of DM and cirrhosis.
 
Univariate analysis (Table 1) showed that compared with the cirrhotic patients, the HCC patients had a higher percentage of males (P=0.001), a lower percentage of DM (P=0.039), a higher mean artery pressure level (P=0.007), a higher percentage of smokers (P=0.005), a lower mean blood glucose/GLU level (P=0.045), a higher percentage of patients with AFP>400 ng/mL (P<0.001), higher values of white blood cells (P<0.001), hemoglobin (P<0.001) and platelets (P<0.001), increased levels of ALT (P<0.001) and GGT (P<0.001), higher levels of total bilirubin (P=0.018) and albumin (P<0.001), and a lower international normalized ratio (INR) (P<0.001).
 
Based on the results of univariate analysis, sixteen variables were included in the multivariate logistic regression, including male sex, DM, MAP, smoking, white blood cells, AFP, hemoglobin, platelet, ALT, GGT, total bilirubin, albumin, INR, serum sodium, portal vein diameter, and presence of ascites (Table 3). The results of multivariate analysis showed that DM was an independent factor for HCC and the value of OR was below the cut-off point of 1 (OR=0.376; 95% CI, 0.175-0.807; P=0.012). In addition, eight other variables were significantly different (Table 3).
 
Similar results from HCC patients who were restricted to those with decompensated cirrhosis and compared with decompensated cirrhotics
Because of the lack of pathologic diagnosis in most patients and selection bias, our study population was restricted to HCC patients with decompensated cirrhosis and compared with decompensated cirrhotics. In these patients, biopsy for diagnosis of cirrhosis was unnecessary and the selection bias should not be further considered. Thus 214 patients were analyzed, including 67 HCC patients and 147 cirrhotics. Among them, 58 patients were diagnosed with DM: 13 in the HCC group and 45 in the cirrhotic group (19.4% vs 30.6%, P=0.087). Univariate analysis (Table 1) revealed that compared with decompensated cirrhotic patients, the HCC patients had a higher percentage of males, a higher percentage of smokers and alcohol intakers, a higher percentage of patients with AFP>400 ng/mL, a lower blood glucose level, elevated white blood cells, hemoglobin and platelets, increased levels of ALT and GGT, elevated levels of albumin and total bilirubin, lowered INR, elevated total cholesterol, lowered sodium, wider portal vein diameter, and a higher percentage of patients with ascites. According to the results of univariate analysis, fifteen variables were included in the multivariate logistic regression (Table 3). The similar results were shown by multivariate analysis (DM, OR=0.192; 95% CI, 0.054-0.679; P=0.010).
 
Association between diabetes duration/treatment and HCC risk
Considering the potentially different effects of anti-diabetic agents in the process of hepatocarcinogenesis, we studied the association between DM duration/treatment and HCC risk. To ensure that diabetes was not induced by HCC, this association was restricted to those who were diagnosed with DM more than one year before HCC diagnosis or before control recruitment, including 16 patients in the HCC group and 43 in the cirrhotic group (Table 4). Among the 59 diabetic patients, 29 received oral anti-diabetic regimens (9/16=56.3% vs 20/43=46.5%, P=0.506), 25 received insulin treatment (4/16=25.0% vs 21/43=48.8%, P=0.100), and 11 were dependent on diet alone to control serum glucose level (5/16=31.3% vs 6/43=14.0%, P=0.254). No significant difference was observed between DM duration/treatment and HCC risk, even after adjustment for age, gender, smoking and alcohol drinking after unconditional multivariable logistic regression analysis (Table 4).
 
Comparison of the role of DM with AFP
Although the role of AFP was questioned for early-stage or small HCC by recent studies, AFP has been used as one of the accepted diagnostic criteria in clinical practice. We compared the role of DM with AFP in the progression of cirrhosis to HCC. When the HCC patients with cirrhosis were compared with cirrhotics, contrary to diabetes (Table 3), a completely opposite role of AFP was observed (OR=22.382; 95% CI, 8.400-59.638; P<0.001). Even after the study population was restricted to those HCC patients with decompensated cirrhosis and compared with decompensated cirrhotics, a similar result was demonstrated for the opposite role of diabetes and AFP (OR=28.934; 95% CI, 6.970-120.109; P<0.001).
 
 
Discussion
DM was an independent factor for HCC in the progression of cirrhosis to HCC in our patients with HBV infection. The OR of 0.376 was below the cut-off value of 1, indicating that DM may be a potentially protective factor for HCC in this process. Even after the population was restricted to those HCC patients with decompensated cirrhosis and compared with decompensated cirrhotic patients, a similar result was observed by multivariate analysis while considering the lack of pathological diagnosis in most patients and selection bias. In addition, an opposite role of AFP was observed in the aforementioned analyses, which may provide supporting evidence for our results and conclusion.
 
For the first time, we found that DM may be a potentially protective factor for HCC in the progression of cirrhosis to HCC, at least in our patients with HBV infection. Thus conclusion could be anticipated because many studies have shown that the percentage of diabetics in cirrhosis patients was higher than that in HCC patients.[4-8, 10, 17] This phenomenon was contrary to the deduction that the risk of HCC would be increased among patients with both DM and HBV-related cirrhosis if diabetes was a risk factor in this progression. To clarify this question, more prospective cohort studies could be performed and the conclusion could be validated in more patients, more centers and more countries.
 
The major limitation of the present study is the observational cross-sectional case-control design. In our study, selection bias was the major concern. However, after the study population was restricted to those with decompensated liver function, similar result was observed. For these patients, biopsy for diagnosis of cirrhosis was completely unnecessary. Another limitation is that most of the HCC and cirrhotic patients in our study were diagnosed clinically rather than by biopsy, and the diagnosis of most diabetics was dependent on their self-reported history or fasting serum glucose, not on oral glucose tolerance test.[18] However, we followed strictly the diagnostic criteria recommended by the authorized institutes and used them widely in clinical practice. We believe that our results are more likely applicable in clinical practice.
 
Our conclusion may be contrary to the generally recognized viewpoint that DM is a new risk factor for HCC.[2, 4, 7, 8, 19, 20] But negative conclusion has been drawn from some studies,[21-25] one of which showed that neither DM nor overweight was a risk factor for HCC.[25] Three studies[13, 15, 16] were conducted in patients with HCV infection, and concluded that DM increased the risk of developing HCC, but no information was available on HBV infection. Since cirrhotic patients with HCV infection are more likely to suffer from type-2 DM than those with HBV infection,[26] our study was designed to determine the effect of DM on the development of HCC in HBV-related cirrhosis patients.
 
Our conclusion was also supported by some studies,[27-29] one of which determined the possible effect of metformin on esophageal, gastric, colorectal cancers as well as HCC and pancreatic cancer.[27] It was a prospective cohort study of 800 000 individuals. The results of the study showed that: 1) In patients with diabetes but no anti-hyperglycemic medication, the HCC incidence increased at least two times; 2) In patients on metformin, the HCC incidence decreased to near non-diabetic level; and 3) Adjustment for some covariates made the benefit of metformin more evident (hazard ratio 0.06; 95% CI, 0.02-0.16).[27] The authors of the study concluded that metformin can reduce the HCC incidence in treated diabetics. Similar results were obtained from studies on pancreatic cancer and colorectal cancer, showing that metformin use was associated with reduced risk, and insulin or insulin secretagogue was associated with increased risk in diabetic patients.[28-30]
 
Reports[27-29] showed the protective role of DM in the progression of cirrhosis to HCC was related to different treatment strategies with oral agents, human insulin and insulin analogues, which was not supported by our results due to the relatively limited number of diabetic patients subjected to biguanide (metformin) treatment. Moreover, the protective role of DM may be related to the interaction of hepatitis virus, cirrhosis and diabetes.[31] DM is a risk factor for HCC in hepatitis patients, but it is not a risk factor for HCC in cirrhotic patients. Exogenous insulin or sulphonylurea treatment was associated with an increased incidence of HCC in patients with HCV infection, but not in those with HCV-related cirrhosis.[31] Apart from the above limitations, some possible factors could not be adjusted, for example non-alcoholic fatty liver disease,[32,33] including non-alcoholic steatohepatitis because of the design of the retrospective cross-sectional case-control study.
 
In conclusion, DM is an independent factor for HCC in the progression of cirrhosis to HCC. To clarify the causal relationship between DM and HCC, prospective and experimental studies are required.
 
 
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Received December 12, 2012
Accepted after revision May 4, 2013