Sofia P¹, Karthick Velavan S^2*, Jerold Bose D C³, Balaselvi T⁴

¹Assistant Professor, ^2,3,4Postgraduates, Department of General Medicine, Kanyakumari Medical college, Kanyakumari, Tamil Nadu, INDIA.

Email: skarthickvelavan12@gmail.com

DISCUSSION

Fatty liver is a very common incidental finding which is usually neglected. But now it needs to be given special attention as it is considered to be a forerunner of many diseases especially coronary artery disease. A large number of various studies conducted across the world have shown that NAFLD is associated with obesity, diabetes, insulin resistance and dyslipidemia which are factors which in association with fatty liver make a person vulnerable to develop cardio vascular diseases. Thus these individuals have a lesser life span when compared with those without the above mentioned risk factors. In this study the diagnosis of NAFLD was made based on the ultra-sonographic evaluation of the abdomen. Due to ethical reasons the gold standard test of liver biopsy was not done in the study group. But still USG has a sensitivity of 80% and specificity of 99%.^1,2 The prevalence of NAFLD among patients with diabetes in India is reported to be between 12.5% to 87.5%.^3,4,5 “A study by Mohan et al showed the prevalence of NAFLD to be 54.5%, which was significantly higher in patients with diabetes”.⁵ “Prashanth et al found a high prevalence of NAFLD and NASH in type 2 diabetics, which increased with multiple components of the metabolic syndrome”. “A study conducted by Shobha Luxmi et al showed a 60.8% prevalence of NAFLD among patients with diabetes”39. In this study the prevalence was found to be 65% among patients with diabetes which correlated with the above-mentioned studies. Most of the previous studies conducted in India have shown a higher prevalence of NAFLD among males than in females⁶. This study also showed a higher prevalence of 78.1% among males than the prevalence of 58.8% among the females. The average age of the patients with NAFLD was 54.35 yrs. “Previous studies have shown that the prevalence of fatty liver increases with age and majority of cases occur between 40 and 60 years”^5,7 In our study also the prevalence of NAFLD was high between 41-60 yrs. The average duration of diabetes was found to be around 6.5 years in both the cases and controls. There was no 71 significant correlation between the duration of diabetes and prevalence of NAFLD. p value = 0.668. On analyzing the anthropometry of the population, 58% of the total study population were obese, 27% were overweight and only 15% had a normal BMI. The mean BMI of the patients with fatty liver was found to be 26.32. Their mean waist circumference was 95.2 cm which was higher than the ethnic specific cut off by the IDF. About 82.76% of patients with obesity and 71.95% of them with truncal obesity were found to have fatty liver for which there was significant correlation as compared to previous studies41. Obesity was defined as BMI ≥25 and if overweight individuals were also included in this category the significance might increase further. Fatty liver was prevalent in about 78.18% of the patients who had hypertension and there was significant statistical correlation for this. About 88% of the study population had inadequate glycemic control among which 71.59% had NAFLD which may be considered as an indicator of insulin resistance in these patients. Inadequate glycemic control also had a significant correlation with the prevalence of NAFLD.72 p <0.05. Only fasting and post prandial blood sugar levels were estimated and HBA1C levels were not evaluated. Dyslipidemia was prevalent in about 78% of the study group of which 78.36% had NAFLD. Based on the above statistical evidence since most of the patients had poor glycemic control, hypertension and dyslipidemia it is possible to arrive at a conclusion that patients with these comorbid conditions are at a higher risk of developing NAFLD. Regarding lipid profile low HDL, elevated total cholesterol, LDL and triglycerides were seen in 42%, 62%, 55% and 67% respectively. Among these low HDL, elevated total cholesterol and triglycerides had a statistically significant correlation with the prevalence of NAFLD. Elevated LDL did not correlate with prevalence of NAFLD. About 78.95% of patients with hypertriglyceridemia were found to have NAFLD (p<0.001) with the mean Triglycerides level being 185.72. This was consistent with findings reported in previous studies conducted by Angulo et al42, Donnelly et al43 and Sharabi et al44.73 About 60% of the fatty liver subjects had low HDL levels and the mean HDL was 45.37 and there was a significant negative correlation with the prevalence of NAFLD. Thus like in other previous studies this study also showed that fatty liver negatively correlated with plasma HDL levels^8,9,10. Around 64.62% of fatty liver subjects had high total cholesterol levels and the mean was 210.15 in them. There was a significant positive correlation with total cholesterol levels and fatty liver. P<0.001. About 53.85% of subjects with fatty liver had elevated LDL levels and the mean LDL level was 103.12 in them. But LDL levels did not have a significant correlation with the prevalence of NAFLD (p=0.45) as in previous studies. This was in concordance with the previous studies conducted by Giovanni Targer et al45 and Vijay Viswanathan et al28. About 71 % of the study population had high Non HDL-C levels. Among them, 22%, 31% and 18% had mild, moderate and severely high Non HDL-C levels. About 76.92% of patients with NAFLD had high Non HDL-C levels. More than 60% of these patients had moderate to severely high levels of Non HDL-C. There was a significant statistical correlation 74 between Non HDL-C and NAFLD. p value = 0.002. “Zelber et al has shown that Non HDL-C independently predicts new onset NAFLD46.” Our results were in concordance with the above study and the study conducted by Sangyeoup et al47. ALT levels were found to be high among 61.54% of individuals in the fatty liver group than 25.71% in the non fatty liver group. The mean ALT level was 47.41 in the fatty liver group which was higher than that of non fatty liver group. Moreover this study showed a significant correlation with high ALT levels and fatty liver (p<0.001). This was consistent with the results of various previous studies26. AST levels were found to be high among 70.77 % of individuals with fatty liver and 40 % in the non fatty liver group. Mean AST level was 44.38 in the fatty liver group. But, this study did not show significant correlation between AST levels and fatty liver (p=0.14) The presence of Metabolic Syndrome was evaluated according to IDF criteria. About 86.15% of individuals in the fatty liver group had 75 Metabolic Syndrome against 37.14% in the non fatty liver group. (Fig: 14, Table: 15) In this study, Metabolic Syndrome had a positive correlation with the prevalence of NAFLD. This was in concordance with previous study by Marchesini et al48. Regarding the prevalence of the complications of diabetes about 16%, 22%, 21% and 28% had CAD, retinopathy, neuropathy and nephropathy respectively. About 23.08% of individuals with NAFLD had Coronary Artery Disease against only 2.9% in the Non NAFLD group. There was a significant positive correlation with NAFLD and CAD (p = 0.044). This would probably be explained by the higher prevalence of dysglycemia and components of Metabolic Syndrome, which favors early onset atherosclerosis in these patients. Around 27.69% of the patients with fatty liver were found to have diabetic retinopathy against 11.43% in the non fatty liver group. But, there was no significant correlation with the prevalence of NAFLD and diabetic retinopathy (p = 0.201). About 26.15% of individuals with NAFLD were found to have developed diabetic neuropathy against only 11.43% in the non NAFLD group. This also did not show a significant 76 correlation (p = 0.244). About 29.23% of the patients with NAFLD had diabetic nephropathy against 25.71% in the non NAFLD group. This study failed to show a significant correlation between NAFLD and diabetic retinopathy. Overall, among the complications of diabetes, only Coronary Artery Disease showed a positive correlation with NAFLD. The other complications like retinopathy, neuropathy and nephropathy did not have a significant correlation with NAFLD. This was only partially consistent with the results of the study conducted by Viswanathan et al²⁸. The limitations of this study are as follows: There was a selection bias as all the participants were included from a tertiary care hospital, sex distribution was unequal with less number of male participants, other tests like anti nuclear antibody, anti smooth muscle antibody, anti mitochondrial antibody, serum ferritin were not done, the gold standard test of liver biopsy was not done due to ethical reasons and fatty liver was diagnosed only by ultrasound. Hence, the results could not be compared with the severity of NAFLD.

CONCLUSION

The prevalence of NAFLD was found to be 65% in the study population. Body Mass Index, waist circumference and uncontrolled hypertension were higher in the fatty liver group. Dyslipidemia especially hyper triglyceridemia and low HDL were strongly associated with NAFLD. Non HDL-C is considered as a better predictor of cardiovascular risk and steato hepatitis in patients with NAFLD. Hence lowering Non-HDL cholesterol has a beneficial role in the treatment. Metabolic Syndrome had a significant association with NAFLD. Diabetic complications like Coronary Artery Disease had a statistically significant correlation with NAFLD. All patients with Diabetes should be screened for NAFLD, because these patients develop diabetes related complications earlier. Early diagnosis and treatment of NAFLD can reduce cardiovascular risk in patients with diabetes

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