Cross sectional study of comparison of aspartate aminotransferase to platelet ratio index and fibrosis-4 scores in predicting the degree of fibrosis in NAFLD patients in a tertiary care centre.

Non-alcoholic fatty liver disease (NAFLD), a multifaceted disease, includes a wide spectrum of liver damage, ranging from the accumulation of fat in >5% of hepatocytes (NAFLD) to non-alcoholic steatohepatitis (NASH), characterized by tissue necroinflammation and possible fibrosis at different stages associated with steatosis. 1 NAFLD has undergone a dramatic epidemiological transition, currently the most common chronic liver disease globally, affecting about 25–30% of adults around the world.2

Its pathological spectrum ranges from simple hepatic steatosis to non-alcoholic steatohepatitis (NASH), fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). 3 Recent evidence indicates that NAFLD accounts for approximately 2.4% of global mortality from liver diseases, surpassing both viral hepatitis and alcoholic liver disease in many developed nations. 4

The pathophysiological intersection between NAFLD and aging presents unique clinical challenges due to age-related alterations in hepatic lipid metabolism, characterized by diminished β-oxidation capacity, mitochondrial dysfunction, and increased pro-inflammatory cytokine production with aging. 5,6

Incidence of NAFLD and its related consequences such as cirrhosis is increasing day by day to a large extent, prognostically the condition is of utmost importance. Presence of fibrosis and degree of fibrosis are considered important factors for the prognosis of NAFLD and in predicting the risk of developing cirrhosis and finally hepatocellular carcinoma. 7

To date, the gold standard of diagnosis remains percutaneous liver biopsy. 8 However, the biopsy is not only an expensive procedure, also an invasive with high risk of complications and sampling errors. Therefore, there is a necessity to investigate new non-invasive biomarkers for early diagnosis of fibrosis. 9 Elastography techniques are a range of methods to that non-invasively assess liver stiffness through the measurement of the velocity of propagation of a shear wave generated by a probe. However, these techniques are limited by the presence of obesity, severe congestion and inflammation. 10

There are some non-invasive scores to diagnose the stage of NAFLD such as FIB-4 (fibrosis-4) and APRI (aspartate aminotransferase/platelet index) and NAFLD fibrosis score (NFS). 11, 12 The non-invasive assessment scores are useful to assess liver fibrosis where liver biopsy is not accessible. In support of this a study done by Mosca A, et al., conducted a study to evaluate the usefulness of four fibrosis scores APRI, FIB-4, NAFLD Fibrosis Score [NFS], and Hepamet in predicting different degrees of fibrosis among children with biopsy-proven NAFLD. They reported that, Hepamet and APRI perform better than NFS and FIB-4 for identifying fibrosis in patients with NAFLD. 13

Another study by Xiao G et al., reported that APRI and FIB-4 correlate with liver fibrosis. However, these two models have low accuracy for predicting HBV-related liver fibrosis in HCC patients. 14 In a study by Xiao G et al., conducted a systemic review and meta-analysis, to systematically review the performance of APRI and FIB-4 in hepatitis B virus (HBV) infection in adult patients and compare their advantages and disadvantages. They suggested that APRI and FIB-4 can identify hepatitis B-related fibrosis with a moderate sensitivity and accuracy. 15 However, there are limited studies were available. Therefore, the present study was aimed to assess the efficacy and performance of the fibrosis index based on 2 factors FIB-4 and APRI to predict the degree of fibrosis in NAFLD patients.

The present study was conducted in Department of General Medicine, Akash Institute of Medical Sciences and Research Centre (AIMSRC), Bengaluru, Karnataka, India. This study was initiated after obtaining the Institutional Ethics Committee (AIMSRC/IEC/97/2024-25) and informed consent from all the study subjects. Patients with NAFLD diagnosed through ultrasound subjects were selected for the study after considering the inclusion and exclusion criteria. Patient's history was taken, physical examination was done.

Sample Size Calculation

n=((Z_(1-α/2)^2⋅P⋅Q)/d^2 )

Where:

• Z_(1-α/2) = 1.96 at 95% confidence interval

• P is the prevalence or proportion of APRI = 77.8%

• Q = 100 − P = 100 − 77.8 = 22.2%

• d = 7.78 at 10% of prevalence or proportion

Substituting the values:

n=(((1.96)^2⋅77.8⋅22.2)/(7.78)^2 )

n = 109.6.

The obtained sample size is 110. Simple random sampling method was followed for recruiting the study subjects.

Inclusion Criteria

Subjects willing to participate in the study, patients aged more than 18 years, non-alcoholic patient, patients with diabetes without comorbidities were included in the study.

Exclusion Criteria:

Subjects not willing to participate in the study, patients with hepatitis infections, patients with other conditions altering the liver function test, patients taking hepato-toxic drugs, patients with hemolytic conditions, patients with hypothyroidism, celiac disease, history of myocardial infarction, dermatomyositis were excluded from the study.

Anthropometric measurements

The BMI was calculated by dividing an individual’s weight in kilograms by the square of height in meters. Waist to hip ratio (WHR) was calculated. Demographic data, blood pressure, anthropometrics, clinical details and family history were recorded.

Estimation of biochemical parameters

Five ml fasting venous blood samples were collected from all the study subjects, transferred 2 ml into EDTA tube and 3 ml in plain tube and centrifuged. The serum sample was used for analysis of biochemical parameters such as total cholesterol (cholesterol oxidase/peroxidase), triglycerides (glycerol phosphate oxidase/peroxidase), HDLC (HDLC- Direct) were estimated by using Biochemistry fully auto analyzer. LDLC and VLDLC were calculated by Frieldwald’s formula. Serum total & direct bilirubin (Diazo), AST (IFCC), ALT (IFCC), ALP (PNP-AMP). EDTA samples were used for complete blood count (CBC) analysis.

Calculation of Non-invasive Fibrosis Scores:

In this study, we calculated the APRI and FIB-4 scores.

The APRI scores

APRI=((AST Level (U/L))/(AST (Upper Limit of Normal) (IU/L)))/(Platelet Count(〖10〗^9/L) )×100                 

FIB-4 scores were calculated by using the formula: 

FIB-4=(Age (years)×AST Level (U/L))/(Platelet Count(〖10〗^9/L)×√(ALT Level (U/L)))                   

Statistical Analysis

Results were expressed as mean±SD. Spearman’s rho correlation was applied to correlate APRI and FIB-4 with study parameters. The p value (p <0.05) was considered as statistically significant. Data analysis was done by using SPSS 22.0.

In the present study, mean age of the study subjects 46.1±13.9 years, BMI 24.9±1.0 kg/m², WHR 0.86±0.06, platelets 300.0±76.0, Total Bilirubin 0.78±0.45 mg/dl, Direct Bilirubin 0.33±0.30 mg/dl, AST 64.8±28.4 IU/L, ALT 57.7±22.2 IU/L, ALP 96.7±30.9, total cholesterol 189.0±29.8 mg/dl, Triglycerides 189.0±29.8 mg/dl, HDLC 39.2±9.1 mg/dl, LDLC 103.4±40.1 mg/dl, APRI 0.61±0.44, and FIB-4 value 1.52±0.9.1 as shown in table 1.

Table 1. Demographic biochemical parameters of study subjects.

In this study, APRI was significantly negatively correlated with platelets (r=-0.544) and positively correlated with AST (r=0.791), ALT (r=0.249) and FIB-4 (r=0.613) whereas FIB-4 showed negative correlation with platelets (r=-0.429), ALT (r=-0.212) and APRI (r=-0.117) and positively correlated with age (r=0.612), AST (r=0.458), TGL (r=.079) and HDLC (r=0.626) as shown in table 2.

Table 2: Correlation of APRI and FIB-4 with study parameters.

**. Correlation is significant at the 0.01 level (2-tailed).

*. Correlation is significant at the 0.05 level (2-tailed).

Table 3 shows the staging of NAFLD based on APRI and FIB-4 score.

Table 3: Staging NAFLD based on APRI and FIB-4 scores

The prevalence of NAFLD is increasing globally.  The progression and stage of liver fibrosis determine the prognosis and treatment of the disease. For clinical decision-making and follow-up, accurate quantification of liver fibrosis is of paramount importance. Only a liver histological examination can accurately confirm the existence of concomitant liver fibrosis, necroinflammatory activity, and steatosis. Liver biopsy is the gold standard test for evaluating liver fibrosis stages and due to the invasive nature of the procedure, the small size of the specimen, sampling risks, and inter-observer variability in the histopathological examination can restrict the routine use of liver biopsy. 16  Due to the non-invasive nature of transient elastography, several recommendations also state that it is an excellent way to assess liver fibrosis. 17

In the present, APRI was significantly negatively correlated with platelets (r=-0.544) and positively correlated with AST (r=0.791), ALT (r=0.249) and FIB-4 (r=0.613) whereas FIB-4 showed negative correlation with platelets (r=-0.429), ALT (r=-0.212) and APRI (r=-0.117) and positively correlated with age (r=0.612), AST (r=0.458), TGL (r=.079) and HDLC (r=0.626).

In support of our study, a cross-sectional study conducted by Amernia B et al., including patients with NAFLD to compare fibrosis-4 (FIB-4), aspartate aminotransferase (AST) to platelet ratio index (APRI), and aspartate aminotransferase/alanine aminotransferase (AST/ALT) ratio with FibroScan for the assessment of hepatic fibrosis in patients with NAFLD. They reported that APRI appears to be the most appropriate substitute of FibroScan for the detection of significant fibrosis in NAFLD patients. FIB-4 was the second best, suggesting that in case of FibroScan unavailability, APRI and FIB-4 are the best indices to assess liver fibrosis in NAFLD patients. 18 Similarly, another cross-sectional study conducted by Moosavy SH et al., included patients with Chronic hepatitis B (CHB) reported that, APRI can rule out 95.4% of F3/F4 of liver fibrosis and rule in any grade of liver fibrosis in CHB patients by 90.78%. Therefore, APRI appears to be the best substitute for FibroScan in the assessment of liver fibrosis in patients with CHB. 19  In a comparative cross-sectional study by Ikram H et al., to compare the extent of liver fibrosis using fibroscan and subsequently compare it with AST/ALT ratio and AST to platelet ratio index (APRI). They reported that Early fibro scan testing and serum markers can help in early diagnosis and timely initiation of treatment for NAFLD. 20

Alam M.S et al., conducted a cross-sectional study to evaluate the diagnostic performance of non-invasive hepatic indices (FIB-4, APRI, and AST/ALT ratio) compared with FibroScan for assessing the stage of fibrosis in individuals with NAFLD and T2DM. They reported that FIB-4 was the most reliable non-invasive tool for detecting advanced fibrosis in patients with NAFLD and T2DM. 21.

The present study may conclude that, APRI was significantly negatively correlated with platelets and positively correlated with AST, ALT and FIB-4, whereas FIB-4 showed negative correlation with platelets, ALT, APRI and positively correlated with age, AST, TGL and HDLC. Therefore, APRI and FIB-4 may serve as non-invasive tool for fibrosis in patients with NAFLD. Further studies with large sample size are recommended.

1.       Mann JP, Valenti I, Scorletti E, Byrne CD, Nobili V. Non-alcoholic fatty liver disease in children. Semin Liver Dis. 2018;38:1-13. https://doi.org/10.1055/s-0038-1627456

2.       Younossi ZM, Koenig AB, Abdelatif D, Fazel Y, Henry L, Wymer M. Global epidemiology of nonalcoholic fatty liver disease-Meta-analytic assessment of prevalence, incidence, and outcomes. Hepatology. 2016;64(1):73–84. https://doi.org/10.1002/hep.28431

3.       Chalasani N, Younossi Z, Lavine JE, Charlton M, Cusi K, Rinella M, et al. The diagnosis and management of nonalcoholic fatty liver disease: practice guidance from the American Association for the Study of Liver Diseases. Hepatology. 2018;67(1):328–57. https://doi.org/10.1002/hep.29367

4.       Estes C, Razavi H, Loomba R, Younossi Z, Sanyal AJ. Modeling the epidemic of nonalcoholic fatty liver disease demonstrates an exponential increase in burden of disease. Hepatology. 2018;67(1):123–33. https://doi.org/10.1002/hep.29466

5.       Mantovani A, Byrne CD, Bonora E, Targher G. Nonalcoholic fatty liver disease and risk of incident type 2 diabetes: a meta-analysis. Diabetes Care. 2018;41(2):372–82. https://doi.org/10.2337/dc17-1902

6.       Rinella ME. Nonalcoholic fatty liver disease: a systematic review. JAMA. 2015;313(22):2263–73. https://doi.org/10.1001/jama.2015.5370

7.       Chalasani N, Younossi Z, Lavine JE, Diehl AM, Brunt EM, Cusi K, et al. The diagnosis and management of non-alcoholic fatty liver disease: practice guideline by the American Association for the Study of Liver Diseases, American College of Gastroenterology, and the American Gastroenterological Association. Hepatology. 2012;55:2005-2023. https://doi.org/10.1002/hep.25762

8.       Vajro P, Lenta S, Socha P, Dhawan A, McKiernan P, Baumann U et al. Diagnosis of nonalcoholic fatty liver disease in children and adolescents: position paper of the ESPGHAN Hepatology Committee. J Pediatr Gastroenterol Nutr. 2012; 54:700-13. https://doi.org/10.1097/mpg.0b013e318252a13f

9.       Angulo P, Hui JM, Marchesini G, Bugianesi E, George J, Farrell GC, et al. The NAFLD fibrosis score: a noninvasive system that identifies liver fibrosis in patients with NAFLD. Hepatology. 2007; 45:846-54. https://doi.org/10.1002/hep.21496

10.    Banc-Husu AM, Bass LM. Transient elastography in pediatric liver disease. J Pediatr Gastroenterol Nutr. 2021; 73:141- 4. https://doi.org/10.1097/mpg.0000000000003168 

11.    Mansoor S, Yerian L, Kohli R, Xanthakos S, Angulo P, Ling S, et al. The evaluation of hepatic fibrosis scores in children with nonalcoholic fatty liver disease. Dig Dis Sci. 2015; 60:1440–7. https://doi.org/10.1007/s10620-014-3494-7

12.    Zambrano-Huailla R, Guedes L, Stefano JT, de Souza AAA, Marciano S, Yvamoto E, et al., Diagnostic performance of three non-invasive fibrosis scores (Hepamet, FIB-4, NAFLD fibrosis score) in NAFLD patients from a mixed Latin American population. Ann Hepatol. 2020;19(6):622-626. https://doi.org/10.1016/j.aohep.2020.08.066

13.    Mosca A, Della Volpe L, Alisi A, Veraldi S, Francalanci P and Maggiore G.Non-Invasive Diagnostic Test for Advanced Fibrosis in Adolescents With Non-Alcoholic Fatty Liver Disease. Front. Pediatr.2022;10:885-576. https://doi.org/ 10.3389/ fped. 2022.885576

14.    Xiao G, Zhu F, Wang M, Zhang H, Ye D, Yang J et al., Diagnostic accuracy of APRI and FIB-4 for predicting hepatitis B virus-related liver fibrosis accompanied with hepatocellular carcinoma. Digestive and Liver Disease. 2016;48(10):1220-1226. https://doi.org/10.1016/j.dld.2016.06.001

15.    Xiao, G., Yang, J. and Yan, L. Comparison of diagnostic accuracy of aspartate aminotransferase to platelet ratio index and fibrosis-4 index for detecting liver fibrosis in adult patients with chronic hepatitis B virus infection: A systemic review and meta-analysis. Hepatology. 2015;61: 292-302. https://doi.org/10.1002/hep.27382

16.    Castera L, Pinzani M. Biopsy and non-invasive methods for the diagnosis of liver fibrosis: does it take two to tango? Gut. 2010;59(7):861-866. https://doi.org/10.1136/gut.2010.214650

17.    EASL recommendations on treatment of hepatitis C 2016. European Association for the Study of the Liver. J Hepatol. 2017;66:153–194. https://doi.org/10.1016/j.jhep. 2016.09.001

18.    Amernia B, Moosavy SH, Banookh F, Zoghi G. FIB-4, APRI, and AST/ALT ratio compared to FibroScan for the assessment of hepatic fibrosis in patients with non-alcoholic fatty liver disease in Bandar Abbas, Iran. BMC Gastroenterol. 2021;21(1):453. https://doi.org/10.1186/s12876-021-02038-3 

19.    Moosavy SH, Eftekhar E, Davoodian P, Nejatizadeh A, Shadman M, Zare S, et al., AST/ALT ratio, APRI, and FIB-4 compared to FibroScan for the assessment of liver fibrosis in patients with chronic hepatitis B in Bandar Abbas, Hormozgan, Iran. BMC Gastroenterol. 2023;23(1):145. https://doi.org/10.1186/s12876-023-02780-w 

20.    Ikram H, Jaffar SR, Hayat A, Khattak M, Majeed N, Naeem A. Fibroscan Compared to Aspartate Aminotransferase to Platelet Ratio Index (APRI) and Aspartate Aminotransferase to Alanine Aminotransferase Ratio (AST to ALT) in the Assessment of Liver Fibrosis in Patients with Non-Alcoholic Fatty Liver Disease in a Tertiary Care Hospital. Pak Armed Forces Med J. 2022; 72(2): 676-680. https://doi.org/ 10.51253/pafmj.v72i2.7152

21.    Alam M.S, Kalam S.T, Khan M.I, Ahmed J, Saha R, Kamrul-Hasan ABM. Comparison of FIB-4, APRI and AST/ALT ratio with FibroScan in patients with NAFLD and type 2 diabetes: a single-center study from Bangladesh. Egypt Liver Journal2025;15, 38. https://doi.org/10.1186/s43066-025-00442-y.