Non-alcoholic fatty liver disease among patients undergoing ultra-sonography abdomen and its associated factors in a tertiary care hospital, Kakinada

INTRODUCTION

Non-alcoholic fatty liver disease (NAFLD) is a condition defined by significant lipid accumulation (5-10%) in hepatic tissue in the absence of significant chronic alcohol consumption.¹ The majority of NAFLD patients have simple steatosis, or increased liver fat content. However, some patients also have non-alcoholic steatohepatitis (NASH), which is characterised by increasing hepatic inflammation. Up to 20% of patients also have progressive hepatic fibrosis, which may lead to cirrhosis or liver failure in the future.^2–4

Non-alcoholic fatty liver disease (NAFLD is one of the most significant causes of liver disease in the world. The worldwide prevalence of Non-alcoholic fatty liver disease (NAFLD) is about 30% and 33.07% in South-East Asia 29.7% in East Asia 33.83% in South Asia.⁵ overall pooled prevalence of NAFLD in India is 38.6% among adults and 35.4% among children.⁶ The pathogenesis is multifactorial, involving insulin resistance, visceral obesity, atherogenic dyslipidaemia, oxidative stress, and inflammation.^7–10 While simple steatosis in NAFLD does not lead to a significant increase in short-term morbidity or mortality, progression to NASH greatly raises the risks of developing cirrhosis, liver failure, and hepatocellular carcinoma.⁴ The odds of progression to advanced liver disease, including hepatic decompensation and hepatocellular carcinoma (HCC), are higher in patients with NASH than those with NAFLD.¹¹ Gender also plays a role, with NAFLD being more common in men, while women have a higher risk of advanced fibrosis.¹² NAFLD is more prevalent in older individuals, with the risk increasing as age advances. Metabolic syndrome is a significant risk factor, with 70-90% of patients with NAFLD having metabolic syndrome.¹³ Dietary factors, such as high cholesterol and saturated fats, increase the risk of NAFLD, while high fructose intake and low carbohydrate intake may also play a role. Interestingly, caffeine intake may have a protective effect.¹⁴ Finally, genetic factors, particularly the PNPLA3 gene, are known to contribute to the development of NAFLD.¹⁵ Insulin resistance and obesity are common in NAFLD patients. Many of patients with type 2 DM develops NAFLD.¹⁶ A study reported of NAFLD presence of NAFLD in individuals between the ages of 45 and 54 is a significant and independent predictor of death due to cardiovascular causes.¹⁷ An additional research study revealed that individuals with NAFLD had a 13% increase in carotid intima-media thickness and a higher incidence of plaque formation.¹⁸ A surprisingly large proportion of the general population is not aware of this silent but concerning disease.¹⁹ The MOHFW has identified the significance of NAFLD and included in the NPCDCS programme which is now renamed as NPNCD.²⁰ This study is taken up with the aim of drawing attention of NCP to this problem by assessing the magnitude of ultrasound-diagnosed NAFLD and identifying the associated factors to assess the prevalence of ultra-sonography-diagnosed NAFLD and its associated risk factors.

METHODS

Study design

This was an observational, analytical, cross-sectional study conducted at a tertiary care hospital in Kakinada, Andhra Pradesh, from June to July 2022.

Study population and setting

The study population were adult patients, either inpatient or outpatient, who were referred for ultrasound abdomen to Radiology department, Government General Hospital, Kakinada, Andhra Pradesh. The inclusion criteria were patients about 18 years of age and below 60 years. Exclusion criteria included patients with hepatobiliary diseases, malignancies, ascites, chronic drug abuse, and alcohol abuse (more than 20 g/day).

Sample size and sampling technique

The sample size was calculated to be 97, including a 10% attrition rate. The sample size was determined using the formula n=4pq/l², where the prevalence of NAFLD in hospital settings was taken as 32% based on pilot study. Total of 100 subjects were selected by using simple random sampling from the list of daily registered patients for ultrasound in the radiology department.

Study instrument and variables

A pretested validated case record form was used to collect data on age, gender, lifestyle risk factors, body mass index, waist circumference, and waist/hip ratio and ultrasound. Additionally, detailed information on cooking oil consumption, lifestyle habits, and dietary habits were obtained.

Ethical considerations

Institutional Ethics Committee approval was obtained prior to conducting the study.

Data collection

After obtaining informed consent, a pretested validated case record form was used to collect data from eligible subjects regarding their demographics, co-morbidities, diet, and anthropometry. Anthropometry measurements were BMI and waist-hip ratio. All individuals underwent an ultrasound examination by Radiologist.²¹ Additionally, detained information on cooking oil consumption, lifestyle habits, and dietary habits was obtained. The data was collected using Google Forms.

Statistical analysis

After collection, the obtained data analysed by using Microsoft Excel and SPSS software (version 21.0). Prior to performing statistical tests, the normality of continuous variables was assessed. An independent sample t-test was used for the comparison of continuous variables and Chi-square test for qualitative variables. Non-parametric tests, such as the Mann-Whitney U test, were employed when data violated the assumptions of normality. P value below 0.05 was considered as statistically significant. Ninety-five per cent confidence intervals (95% Confidence interval (CI) for the measures of association were calculated and reported.

RESULTS

The present study, conducted on 100 sample populations, found that there was a prevalence of 41% of NAFLD among the study population, with a mean age of 35.46 ±10.8 years and a mean weight of 65.5 kg. The mean BMI of the sample population was 25.79±4.89. The mean waist-hip ratio was 0.93±0.11 cm. The mean oil consumption per person was 1.1±0.49 kg per month.

Table 1 shows the socio-demographic profile of the subjects. Out of 100 subjects, 50 were male and 50 were female, the majority were Hindu (81%), followed by Christians (16%) and Muslims (3%). In terms of age distribution, 40 subjects were between 18 and 30 years old, 35 were >30 years and 25 were above 45 years old. The highest proportion of subjects had primary education (34%), followed by secondary education (31%), illiterate (23%), and degree holders (12%). Many were engaged in daily wage and agriculture (49%), followed by housewives (27%), unemployed (12%), technicians (8%), clerks (2%), and professionals (2%).

Table 2 shows the anthropometric measurements. Out of 100 subjects 17 were obese, 35 were pre-obese, 6 were underweight, BMI was normal among 42%. High waist-hip ratio seen in 65%. Only 20% reported exercising. There was significant association between high BMI with NAFLD in the study population. There was also a significant association between waist-hip ratio and NAFLD (χ²=12.66, p<0.000). In terms of health factors, 11% had a history of diabetes and 20% had a history of hypertension.

*Statistically significant

Table 3 shows association of NAFLD with co-morbidities. The results show that there was a significant association between a history of diabetes mellitus (DM) and NAFLD (χ²=12.72, p<0.000), with a higher prevalence of NAFLD among individuals with a history of DM. There was no significant association between a history of hypertension (HTN) and NAFLD (χ²=0.837, p=0.36). The most commonly used cooking oil was sunflower oil (67%), followed by palm oil at 28%, 1% of subjects used groundnut oil while 4% used rice bran oil. In terms of consumption of non-vegetarian food, 44% reported consuming once in a week, 24% reported consuming twice a week and 21% reported consuming thrice a week. Only 3% reported not consuming any non-vegetarian food.

Table 3 shows the association between dietary habits and NAFLD in the study population. The results show that there was no significant association between the type of cooking oil and NAFLD (χ²=4.6, p=0.201). However, there was a significant association between the amount of cooking oil consumption and NAFLD (χ²=19.25, p<0.01), with a higher prevalence of NAFLD among individuals who consumed >1.24 kg/month of cooking oil. There was no significant association between non-vegetarian consumption and NAFLD (χ²=8.6, p=0.19). There was a significant association between exercise and NAFLD (χ^{^2}=13.39, p=0.000), with a higher prevalence of NAFLD among individuals who did not exercise. Table 4 variables, including BMI, waist circumference, waist-hip ratio, and oil consumption, are associated with NAFLD.

**When the expected count in some cells of a contingency Table is less than 5, continuity correction (also known as Yates’ correction), which adjusts the chi-square value to account for the discrepancy between the discrete and continuous distributions.

^*Unpaired t test; Mann-Whitney U test.

DISCUSSION

Based on the results of the study and the other studies mentioned, it is clear that various factors play a role in the development of non-alcoholic fatty liver disease (NAFLD). In particular, BMI, gender, waist-hip ratio, and lifestyle factors such as diet and exercise have been identified as significant risk factors for NAFLD.^12,13,22,23 The present analytical cross-sectional study found that there was a prevalence of 41% of NAFLD among the study population using ultrasound. A meta-analysis assessment showed a worldwide prevalence is about 30% and 33.07% in South-East Asia 29.7% in East Asia 33.83% in South Asia.⁵ Overall pooled prevalence of NAFLD in India is 38.6% among adults and 35.4% among children A prevalence rate of 49.8% was reported in coastal south India in a population-based study and Type 2 diabetes is a common condition and it regularly coexists with NAFLD and 24.3% of those with NAFLD also had diabetes.^16,24

The mean BMI of the sample population was 25.79 BMI which is considered to be in the overweight category was found to be a significant factor in this study, with a p value of 0.03. This is consistent with the findings of Anand et al, who reported a p value of <0.001 for BMI as a risk factor.²⁵ Gender, age and BMI were also found to be significant risk factors.^22,26,27

The mean waist-hip ratio was 0.93 cm. Waist-hip ratio was found to be a significant factor with a p value of 0.002 in the current study. This is consistent with the results of the study, where an increase in waist and hip ratio was identified as a risk factor for NAFLD. with a p value of 0.000.²⁸

In terms of prevalence, the study found a prevalence of 41% of NLFD among the study population, which is consistent with the prevalence reported by Georgi Kirovski and Doris Schacherer.²¹ Their study also identified lifestyle factors such as increased oil intake and sedentary lifestyle as risk factors for NAFLD, which reinforces the importance of promoting healthy behaviours to prevent and control NAFLD.²¹ Our study shows an increase in cooking oil consumption, which turns to be a significant risk factor as the mean consumption is 1.24 kg per month in the NAFLD population.

Overall, the study adds to the body of literature on the risk factors for NAFLD, with BMI, Waist hip ratio, lack of exercise, overconsumption of oil and coexisting diabetes mellitus identified as a significant factor. The findings of the study are consistent with previous studies, and underscore the importance of lifestyle factors in the prevention and management of NAFLD.²⁹

CONCLUSION

Promoting healthy behaviours to effect life style behaviour change, is critical for prevention and specific control of NAFLD. Future studies could further investigate the role of dietary and exercise interventions in the prevention and treatment of NAFLD

ACKNOWLEDGEMENTS

We would like to thank the study subjects who participated in the study and the Department of Radiology at the Government General Hospital in Kakinada.

Funding: No funding sources

Conflict of interest: None declared

Ethical approval: The study was approved by the Institutional Ethics Committee

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