Biochemical markers of liver damage in patients with non-alcoholic fatty liver disease

Introduction

Excessive fat buildup in hepatocytes without heavy alcohol use characterizes a range of liver diseases known as Non-Alcoholic Fatty Liver Disease (NAFLD). Included in this category are various hepatic abnormalities, such as simple steatosis, non-alcoholic steatohepatitis (NASH), and fibrosis, cirrhosis, and hepatocellular cancer [1,2] . North American Fatty Liver Disease (NAFLD) affects about 25-30% of the adult population globally, making it the most common chronic liver disease. This is due to the worldwide growth in obesity, type 2 diabetes mellitus, and metabolic syndrome [3][4][5] . Multiple factors, including insulin resistance, oxidative stress, dyslipidemia, and inflammatory pathways, contribute to the complicated pathophysiology of non-alcoholic fatty liver disease (NAFLD). The lack of symptoms in the early stages of NAFLD makes it difficult to diagnose until serious liver damage has already taken place. Therefore, in order to detect and track the evolution of the disease early on, it is critical to identify trustworthy noninvasive indicators for liver injury [6,7] . Common biochemical indicators used to evaluate liver function and injury include alanine aminotransferase (ALT), aspartate aminotransferase (AST), gama-glutamyl transferase (GGT), and alkaline phosphatase (ALP). The AST/ALT ratio can shed light on the severity of the condition, and ALT is thought to be the most sensitive indicator of hepatic inflammation in NAFLD. Hepatobiliary dysfunction and oxidative stress linked to NASH may also be indicated by elevated GGT and ALP values [8][9][10] . The most accurate way to diagnose and stage NAFLD is with a liver biopsy, however this invasive procedure is impractical for everyday use. As a result, biochemical indicators are just as important in clinical practice as imaging techniques such as ultrasonography [11] . The purpose of this research is to examine the relationship between NAFLD biochemical markers and clinical factors including glycemic status, body mass index (BMI), and lipid profile in individuals with a diagnosis of the disease. This might be useful for identifying patients at risk of illness development early on and developing better non-invasive diagnostic methods.

Material and Methods

This cross-sectional observational study was undertaken in the department of Biochemistry, Madha Medical College and Research Institute, located in Kovur, Mangadu, Thandalam, Chennai, Tamil Nadu, India, from March 2016 to February 2017. Sixty adult patients diagnosed with Non-Alcoholic Fatty Liver Disease (NAFLD) were enrolled in the study following the acquisition of informed permission. Patients were chosen based on ultrasonographic indications of hepatic steatosis and clinical assessment. Biochemical analyses were conducted to evaluate liver function and metabolic parameters.

Inclusion Criteria

 Adult patients aged between 18 and 65 years.  Diagnosed with NAFLD by abdominal ultrasound showing evidence of hepatic steatosis.  No history of significant alcohol consumption  Willing to provide informed consent Exclusion Criteria:  Patients with known history of viral hepatitis (HBV, HCV), autoimmune hepatitis, or other chronic liver diseases.  Significant alcohol intake above defined thresholds.  Patients with a history of hepatotoxic drug use.  Individuals with diagnosed malignancies, chronic kidney disease  Pregnant or lactating women.

Data Collection and Biochemical Analysis:

The following information was recorded: patient's demographics, medical history, and anthropometric measurements (height, weight, body mass index). Liver Function Tests (LFTs) including ALT, AST, ALP, GGT, total bilirubin, and direct bilirubin were assessed using blood samples obtained after an overnight fast. Lipide profile: Triglycerides, HDL, LDL, and total cholesterol. Blood glucose levels and hemoglobin A1C levels during fasting. Traditional automated biochemical analyzers were used for every research. Another metric was the AST/ALT ratio.

Statistical Analysis:

Utilizing SPSS software, the data were examined. Mean±Standard Deviation (SD) was used to express continuous data, whereas percentages were used for categorical variables. Clinical characteristics (such as body mass index and lipid profile) and biochemical markers were examined for correlations using Pearson's correlation coefficient. Statistical significance was determined by a pvalue less than 0.05.

Results

The research involved 60 individuals who had been diagnosed with NAFLD, or Non-Alcoholic Fatty Liver Disease. Participant demographics and clinical features showed a middle-aged male preponderance with obesity and metabolic comorbidities including type 2 diabetes mellitus, hypertension, dyslipidemia, and a larger proportion of middle-aged men. High levels of liver enzymes, especially alanine aminotransferase (ALT) and aspartate aminotransferase (AST), were detected in most individuals by biochemical testing. Furthermore, glycemic control and lipid profile abnormalities were prevalent.

Discussion

The purpose of this research was to examine the relationship between metabolic parameters and biochemical indicators of liver damage in individuals suffering from Non-Alcoholic Fatty Liver Disease (NAFLD). According to the results, many people with NAFLD also had metabolic syndrome symptoms such obesity, type 2 diabetes, and dyslipidemia, as well as elevated liver enzymes (especially ALT and AST). The metabolic foundations of NAFLD are reinforced by these findings, which are in line with earlier studies [11,12] . Among our cohort, elevated ALT was the most prevalent anomaly, impacting over 70% of the patients. This is consistent with previous research, for example the work of Clark et al. (2003), which found that increased ALT levels were a sensitive indicator of hepatocellular damage in NAFLD. According to Diehl and Day (2006), our patients typically had an AST/ALT ratio below 1, which is indicative of early or moderate NAFLD. A ratio greater than 1, on the other hand, is indicative of advanced fibrosis of the liver or alcoholic liver disease [12,13] . Elevated transaminases were substantially related with obesity and a higher body mass index (BMI), lending credence to the well-established association between excess fat and liver steatosis studied by Chalasani et al., 2018 [14] . Additionally, we discovered strong positive associations between ALT and lipids, fasting glucose, and HbA1c levels. Consistent with previous research, these results show that insulin resistance and hypertriglyceridemia are key factors in NAFLD-related liver damage reported by Marchesini et al., 2003; and Targher et al., 2005 [15,16] . Consistent with other research, 45% of our subjects had increased GGT, which may point to oxidative stress and potential cholestatic involvement (Ruhl & Everhart, 2003) [17] . Mild rise in a limited subgroup of bilirubin values, albeit often within the normal range, may indicate early functional impairment in hepatobiliary excretion. Diabetes and dyslipidemia were associated with an unusually high prevalence of NAFLD. Consistent with previous research, Younossi et al. (2016) found that NAFLD is a marker of cardiovascular risk in addition to being a hepatic sign of metabolic syndrome [18] . A significant consequence of these results concerns the function of routine liver function testing in individuals who are known to have metabolic syndrome. Timely lifestyle and pharmacological changes can be made possible with the early diagnosis of liver dysfunction through biochemical indicators. This can help prevent the progression to nonalcoholic steatohepatitis (NASH) or cirrhosis. Nevertheless, there are some limitations to the study [19,20] . To start with, it couldn't be shown a cause and effect relationship because it was cross-sectional. Additionally, there were ethical and practical considerations that prevented the use of liver biopsies, which are considered the gold standard for NASH diagnosis and fibrosis staging. Results are also not applicable to a broader population due to the small sample size and absence of longitudinal followup. In spite of these caveats, the study highlights the significance of combining metabolic and hepatic evaluations and gives useful information on the biochemical profile of individuals with NAFLD in a real-world clinical context [21,22] .

Conclusion

This study shows that Non-Alcoholic Fatty Liver Disease patients had significant changes in biochemical markers like ALT, AST, and GGT. These higher enzyme levels substantially correlate with metabolic syndrome traits like obesity, insulin resistance, and dyslipidemia, emphasizing the link between metabolic health and hepatic function. Our findings suggest that routine liver enzyme monitoring in atrisk patients like those with type 2 diabetes, hypertension, or central obesity can help detect and treat NAFLD before it progresses to NASH or cirrhosis. Early biochemical testing is critical since early NAFLD is asymptomatic and reversible with lifestyle and pharmaceutical therapies. This study further emphasizes the necessity for interdisciplinary care that includes hepatology, endocrinology, and nutrition to address the complicated metabolic and hepatic elements of the condition. Further longitudinal and interventional studies with bigger populations and liver biopsy correlation are needed to confirm these biochemical markers as disease progression indicators.

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