Combined CTP- IGF-1 Score: A New Score for Assessment of Disease Severity in HCV Related Liver Cirrhosis

Background: Liver is the largest endocrine organ in the body. It is a key organ in insulin mediated metabolism, growth hormone and insulin like growth factors (IGF) pathway. Liver cirrhosis is the end result of many chronic diseases including hepatitis C virus infection. Child-Turcotte-Pugh (CTP) score is the standard used in assessment of hepatic reserve but it has its drawbacks in the form of subjective variables, hepatic encephalopathy and ascites. The aim of this work is to assess IGF-1 in patients with liver cirrhosis, correlate it with CTP score and assess value of modied combined CTP-IGF-1 score. Patients and Methods: 170 patients with CLD (liver cirrhosis) and 72 healthy controls in the study groups were enrolled in the study. All patients were subjected to thorough history, clinical examination and laboratory assessment. IGF-1 was measured and all patients were evaluated using CTP and CTP-IGF-1 scores. Results: IGF1 showed highly signicant low values in the study group in comparison to controls (42.15 ± 27.976 and 66.31 ± 33.084 ng/ml respectively, p <0.001). It showed also highly signicant negative correlation to CTP score in the study group (p < 0.001) with progressive decrements with CTP score stage progression where IGF1 levels were 48.32 ± 28.611, 40.28 ± 25.869 and 18.80 ± 15.953 ng/ml (mean ± standard deviation) in relation to CTP score groups A, B and C respectively (p value < 0.001). The combined CTP-IGF-1 score in comparison to the classic CTP score showed improved area under curve (0.848 and 0.854), sensitivity (71.2% and 88%), negative predictive value (41.7% and 53.7%), false negative results (49 and 19) and accuracy (75.73% and 83.98%) but decreased specicity (97.22% and 61.1%), positive predictive value (99.2% and 91.5%) and higher false positive results (1 and 14) respectively. Conclusion: IGF-1 show progressive decrements with progression of liver cirrhosis and is negatively correlated with CTP score. Addition of IGF-1 to CTP score to formulate combined score improves the AUC, sensitivity, negative predictive value and the accuracy of CTP score and decreases the false negative results.


Introduction
Liver is a major metabolic organ in the body, involved in glucose, lipid and hormone metabolism. Liver is the largest endocrine organ in the body and it is a key organ in insulin-mediated metabolism and insulin like growth factors (IGFs) pathway including insulin like growth factor-1 (IGF-1), insulin like growth fctor-2 (IGF-2) and their binding proteins (IGFBPs) [1,2]. In mammals; IGF-1 is related to post-natal growth mediated by growth hormone and IGF-2 is related to stimulation of foetal and placental growths that are less dependent on growth hormone [3]. Growth factors produced in the liver, including IGF-1 and IGF-2, affect hepatocytes proliferation, differentiation and apoptosis [4].
Liver cirrhosis is the end result of many chronic liver diseases (CLD) including chronic viral hepatitis, alcoholic liver diseases and non-alcoholic fatty liver disease. Liver cirrhosis is characterised by Page 3/13 replacement of liver tissue by brotic tissue, necrosis and regenerating nodules [5,6]. Liver cirrhosis is associated with IGF pathway changes that result in progressive hepatocellular function deterioration [5].
Patients with chronic liver disease show reductions in hepatic response to growth hormone resulting in elevated growth hormone levels and decreased IGFs levels. This leads to clinical features of IGF1 de ciency [6,7]. Negative correlations between IGF1 and International Normalization Ratio (INR) [8] Model for End stage Liver Disease (MELD) score [8] and splenic size [9] was reported, and correlation was positive with serum albumin levels [8,9]. Reduced IGF1 levels were reported in cases with hepatocellular carcinoma (HCC) in comparison to cirrhotics and healthy controls [10]. The Child-Turcotte-Pugh (CTP) scores is the system used to assess hepatic reserve, overall survival and treatment outcomes in patients with chronic liver diseases [11,12].
Aim of the study The aim of this work is to assess IGF1 levels in patients with liver cirrhosis in comparison to healthy controls and correlate IGF1 levels with CTP score in those patients.

Patients And Methods
This is a case-control study that included 170 patients with CLD and 72 healthy controls. CLD (liver cirrhosis) in the study group was caused by chronic hepatitis C virus (HCV) infection. Liver cirrhosis was identi ed by clinical assessment, abdominal ultrasonography (US), and laboratory assessment.
All subjects in the study were assessed by a thorough history and clinical examination, including residency (urban or rural), smoking history, history of chronic diseases including diabetes mellitus and hypertension, history of previous surgical or dental procedures, and history of anti-bilharzial treatment.

Results
This study included 170 patients with chronic HCV related liver cirrhosis and 72 healthy controls. According to CTP score; this study included 93 A, 57 B and 20 C. The demographic data of the study group in comparison to the controls showed that there was no signi cant difference between both groups regarding residency, occupation, smoking history, hypertension history and surgical or dental procedures. Correlation between IGF-1 and CTP score in the study group using Spearman correlation coe cient revealed that there is highly signi cant negative correlation between IGF-1 and CTP score in the study group (p < 0.001) (  Data is expressed as mean and standard deviation or as percentage and frequency. 95% CI: 95% con dence interval of the mean difference between both groups. P is signi cant when 0.05. Data is expressed as mean and standard deviation or as percentage and frequency. 95% CI: 95% con dence interval of the mean difference between both groups. P is signi cant when 0.05, Hb: hemoglobin, WBCs: white blood cells, RBS: random blood sugar, IGF1: insulin like growth factor 1, ALT: alanine transaminase, AST: aspartate transaminase, INR: international normalized ratio, AFP: alpha feto protein.

Discussion
Liver cirrhosis with or without the development of HCC are the end results of many liver diseases including non-alcoholic fatty liver diseases, chronic viral hepatitis, alcoholic liver diseases and autoimmune liver diseases [5,6]. Hepatitis C virus (HCV) infection is a major health problem in Egypt and anti-HCV antibodies were found to be positive in about 20% of Egyptian blood donors [15]. IGF system abnormalities were found in patients with liver cirrhosis. These abnormalities include growth hormone resistance and IGF-1 de ciencies with many metabolic abnormalities as a result [5].
Our study included 170 patients with HCV-related cirrhosis compared to 72 healthy controls. In comparison to the control group, most of the study group were males, which is related to the nature of the disease being more prevalent in males. Also, because the rate of HCV progression is slower in women, the rate of disease-related complications is higher in men [15,16]. In the study group, the history of diabetes mellitus was signi cantly higher (p 0.001) in the study group in comparison to controls. It was found that the risk of DM was four times higher in adults with HCV than in those without HCV [17]. HCV is linked to insulin resistance that is reported to show some improvement after HCV elimination [18,19]. A previous Egyptian study that included 396 chronic HCV infection patients found that a history of injectable anti-Bilharzial treatment was found in 32.3% of cases [20]. The current study shows that positive antibilharzial treatment is signi cantly higher in the study group in comparison to the controls. Anti-Bilharzial treatment may be linked to a risk of HCV infection through the parenteral route.
In our study, serum IGF-1 levels were found to be signi cantly (p value 0.001, 95% CI 12.24, 36.06) lower in cases with HCV related liver cirrhosis in comparison to normal controls (42. 15 27.976 and 66.31 33.084 ng/ml, respectively). Similar results were found by Vyzantiadis and colleagues, who studied 40 patients with liver cirrhosis due to different etiologies and found that serum IGF-1 levels were signi cantly lower in cases with liver cirrhosis in comparison to 20 controls (57.4 7.0 ng/mL and 198.8 16.3 ng/mL, respectively, p = 0.0000001) [22]. Raslan et al. studied 30 patients with chronic HCV infection (14 with cirrhosis) and 11 healthy controls and found that patients with liver cirrhosis had signi cantly lower IGF-1 levels (p value 0.001) [22]. The numbers of both cases and controls in these studies were low, and some of them had mixed etiologies of liver cirrhosis. Low serum IGF1 levels in patients with liver cirrhosis may be related to the impaired synthetic function of the liver with progressive deterioration with disease progression. Also, growth hormone receptors were found to show lower expression in the hepatic tissue of these patients [23,24]. Interestingly, we found that serum IGF-1 levels show progressive reduction with the progression of liver cirrhosis, indicated by higher CTP scores. Our study included 93 CTP A, 57 CTP B, and 20 CTP C patients with serum IGF-1 levels of 48.32 28.611, 40.28 25.869, and 18.80 15.953 ng/ml, respectively (p value 0.001). A highly signi cant negative correlation (-0.318, p value 0.001) was found between serum IGF-1 levels and CTP scores in our study group. Ronsoni and colleagues found that serum IGF-1 levels were negatively correlated with CTP score and MELD score in 74 patients with liver cirrhosis and signi cantly lower values of serum IGF-1 were observed in patients with higher CTP classes (P 0.05). [25]. Vyzantiadis and colleagues found that serum IGF-1 levels were signi cantly lower in cases with liver cirrhosis CTP B and C in comparison to cirrhotics with CTP A. Interestingly, comparison of the cases with CTP A (n = 26) in their study showed that there was no signi cant difference between viral and non-viral cirrhosis regarding serum IGF-1 levels, indicating that the cause of liver cirrhosis has a limited role and it is the stage of cirrhosis and CTP score that signi cantly affect serum IGF-1 levels [22]. Another study found that there was a statistically non-signi cant negative correlation between HCV viral load and serum IGF-1 levels [26]. Another study revealed that serum IGF-1 levels show progressive decrement with liver cirrhosis progression, namely higher CTP scores [27]. Of importance, Castro and colleagues found that serum IGF-1 levels returned to normal 6 months after orthotopic liver transplantation [28]. These data suggest that progression of liver cirrhosis is associated with a decrement in serum IGF-1 levels, probably due to progressive deterioration of hepatic synthetic functions and may be related to growth hormone insensitivity; these abnormalities may be corrected after liver transplantation.
Although CTP score has its drawbacks in the form of incorporation of two variables that are subjective, namely hepatic encephalopathy and ascites, it has been used for decades as the staging and prognostic method for cases of liver cirrhosis [29,30]. This had led to the development of ideas of processing of new scores that can avoid or at least decrease the effect of these subjective variables, hepatic encephalopathy and ascites. In our study; comparison of serum IGF-1, CTP score and combined CTP-IGF-form of reduced speci city (97.22% and 61.1%), positive predictive value (99.2% and 91.5%) and false positive results (1 and 14) for CTP score and combined CTP-IGF-1 score respectively.

Conclusion
IGF-1 showed progressive decrements with the progression of liver cirrhosis and is negatively correlated with the CTP score. The addition of IGF-1 to the CTP score to formulate a combined score improved the AUC, sensitivity, negative predictive value, and accuracy of the CTP score and decreased the false negative results.

Declarations
Financial support and sponsorship Nil.

Con icts of interest
There are no con icts of interest. Ethics.
The study protocol was investigated and approved by medical ethics research team, Faculty of Medicine in Mansoura University. Every case, after guaranteeing privacy, has given informed written consent. All methods were performed in accordance with relevant guidelines and regulations.

Figure 1
Roc curve for IGF-1, CTP score and their combination in differentiating liver cirrhosis.