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Background:  The perception of nonalcoholic fatty liver disease (NAFLD) as an infrequent and benign condition is swiftly altering in developing countries as there has been an upsurge in non alcoholic fatty liver disease in Asia-Pacific region. NAFLD develops across all age groups and societies and is recognized to occur in 14%–30% of the common population.  The foremost risk factors for NAFLD such as central obesity, diabetes mellitus, insulin resistance, dyslipidemia, hypertension, hypertriglyceridemia are currently predominant and puts a very large population at risk of evolving hepatic steatosis in the coming decades . Material and Methods:  It was a hospital based case control study carried out in the Department of Biochemistry of Manipal Teaching Hospital, Pokhara, Nepal between 1 st January 2010 and 31 st Dec 2010. The variables collected were age, gender, fasting blood glucose, total cholesterol, low density lipoproteins, triglycerides, high density lipoproteins, very low density lipoproteins, aspartate transaminase, alanine transaminase . Results:  Of the 200 patients of non alcoholic fatty liver disease patients   with diabetes mellitus, all  the variables except triglycerides shows insignificant disparity in relation to gender. The perceptible difference was observed in mean values of triglycerides for cases of NALFD between diabetes (218.25 ± SD 73.68) and non diabetic subjects (177.54 ± SD73.45) (p=.0001). The mean values of HDL did not illustrate much difference in cases of NALFD with diabetes (41.54 ± SD2.13) and non diabetic subjects (44.24 ± SD2.05). Conclusion:  Public health initiatives are undoubtedly of the essence to halt or turn around the global 'diabesity' pandemic, the causal basis of NAFLD. Management of patients with NAFLD should be aimed at treating metabolic risk factors such as hyperglycemia and hypertriglyceridemia . Successful lifestyle adaptation with increased exercise and decreased food intake is able to remove the accumulation of liver fat and can reverse insulin resistance. Key words: Hepatic steatosis; Diabetes mellitus; Risk factors; Nepal. DOI: http://dx.doi.org/10.3126/nje.v1i2.5135 Nepal Journal of Epidemiology 2011;1 (2):51-56


Background
The perception of nonalcoholic fatty liver disease (NAFLD) as an infrequent and benign condition is swiftly altering in developing countries as there has been an upsurge in non alcoholic fatty liver disease in Asia-Pacific region.NAFLD transpires across all age groups and societies and is recognized to occur in 14%-30% of the common population 1 .The foremost risk factors for NAFLD such as central obesity, diabetes mellitus, insulin resistance dyslipidemia, hypertension and hypertriglyceridemia currently prevail and puts a very large population at risk of evolving and progression of hepatic steatosis in the coming decades.
Pathogenetic insight of NAFLD include overnutrition, insulin resistance (IR) and genetic aspects 2 .NAFLD and type 2 diabetes mellitus recurrently coincide as both contribute to the pathogenic abnormalities of excess adiposity and insulin resistance 3 .Roughly 70% of persons with non insulin dependent diabetes mellitus have a fatty liver and the disease trails a more aggressive course with necro-inflammation and fibrosis in diabetes 4   .Non-insulindependent diabetes mellitus is a multifaceted metabolic disorder that involves numerous biochemical abnormalities, a heterogeneous clinical picture, and a polygenic genetic module.The pathophysiologic state of non insulin dependent diabetes mellitus encompasses increased basal hepatic glucose production, decreased insulin-mediated glucose consumption in target tissues and reformed pancreatic function with decreased beta cell function and enhanced glucagon secretion.In non-insulin dependent diabetes mellitus, there is compromised autophosphorylation-kinase activity of insulin receptors when sequestered from adipocytes, liver, erythrocytes and skeletal muscles, leading to insulin resistance 5 .Insulin resistance plays a vital role in NAFLD pathogenesis.Insulin resistance is often allied with chronic low-grade inflammation, and several mediators released from immune cells and adipocytes may lead to hepatocellular injury and liver disease progression .The objective of our study was concerned primarily to correlate foremost risk factors involved in the pathogenesis of hepatic steatosis, in order to prevent the succession of complications in Pokhara valley.  .The transaminases (AST and ALT) were estimated by liqui uv test 13.All these laboratory parameters were analysed using Human reagent kits and with the help of semi autoanalyser (Human, Germany).Analysis was done using descriptive statistics and testing of hypothesis.The data was analyzed using Excel 2003, R 2.8.0 Statistical Package for the Social Sciences (SPSS) for Windows Version 16.0 (SPSS Inc; Chicago, IL, USA) and the EPI Info 3.5.1 Windows Version.The Chi-square test was used to examine the association between different variables.Z-test was used to compare the significance difference between two variables.A p-value of < 0.05 (twotailed) was used to establish statistical significance.

Selection of Subjects:
Inclusion criteria: 200 patients with Diabetes Mellitus who sought treatment for diabetes at the endocrinology unit of Medicine Department in Manipal Teaching Hospital between 1 st January 2010 and 31 st Dec 2010 were evaluated.Subjects were subsequently divided into groups of normal glucose (NG) and DM.According to the American Diabetes Association guidelines, subjects with normal fasting glucose had values below 100 mg/dL and subjects with DM were defined by fasting glucose above 126 mg/dL 14 .200 DM patients were compared with a control group of 200 healthy adults with no family history of diabetes.Healthy controls were volunteers employed at Manipal Teaching Hospital, Pokhara.Evidence of fatty liver was obtained by performing ultrasound of the abdomen.Ultrasound demonstrating diffusely increased liver echogenicity with blurring of the intrahepatic vessels and diaphragm, or bright hepatic echogenicity with poor penetration of the posterior hepatic segments and intrahepatic vessels with indication of contrast between the liver and kidney confirms the diagnosis of non alcoholic Exclusion criteria: Subjects also were excluded from the diagnosis of NAFLD when they were having extreme alcohol ingestion (women: ≥20 g/wk, men: ≥30 g/wk), positive hepatitis B surface antigen (HBsAg) or anti-hepatitis C virus antibody (anti-HCV), pregnancy, entire parental nutrition, jejuneal bypass or extensive small bowel resection, or other known liver diseases like hepatoma, as determined by history, physical examination and screenisng blood tests.Subjects who had ingested drugs known to produce fatty liver disease such as steroids, estrogens, amiodarone, tamoxifen or other chemotherapeutic agents within the previous 6 months were also excluded from our present study.

Results
Of the 200 cases of NALFD, there was the perceptible difference in mean values of triglycerides between diabetes and non diabetic subjects.Of the 200 cases of DM, the moderate difference was perceived in mean values of triglycerides with NALFD and no NALFD patients.

Table 1: Gender wise comparison of non alcoholic liver disease patients with diabetes mellitus cases
* Statistically significant (p<0.05)Table 1 depicts that of the 200 patients of non alcoholic fatty liver disease patients with diabetes mellitus, all the variables except triglycerides shows insignificant disparity in relation to gender.The mean values of triglycerides were more in males (224.51 ± SD76.60) when compared to females (204.17 ± SD65.06) and above the upper limit of normal reference range.3 depicts the differences in distribution of variables for cases of NALFD with DM patients and subjects with no family history of diabetes.There was significant difference in mean values of fasting blood sugar between diabetes (159.82 ± SD44.01) and non diabetic subjects (89.66 ± SD10.66) (p=.0001) for cases of NALFD.There was slight variation in mean values of total cholesterol for cases of NALFD with diabetes (203.14 ± SD43.11) and non diabetic subjects (183.43 ± SD40.66) (p=.0001).The perceptible difference was observed in mean values of triglycerides for cases of NALFD between diabetes (218.25 ± SD 73.68) and non diabetic subjects (177.54 ± SD73.45) (p=.0001).The mean values of HDL did not illustrate much difference in cases of NALFD with diabetes (41.54 ± SD2.13) and non diabetic subjects (44.24 ± SD2.05).There was mild difference for the mean values of LDL difference in cases of NALFD with diabetes (116.58±SD38.09) and non diabetic subjects (99.03 ± SD38.11) but well within normal reference range.The mean values of AST did not show much variation in non alcoholic fatty liver disease patients with (29.15 ± SD3.59) or without (25.44 ± SD3.57) diabetes mellitus.Similarly, the mean values of ALT were also in the normal reference range in cases of NALFD with diabetes and non diabetic subjects. .Of the 200 patients of non alcoholic fatty liver disease patients with diabetes mellitus, all the variables except triglycerides showed insignificant disparity in relation to gender.The mean values of triglycerides were more in males (224.51 ± SD76.60) (CI 211.47, 237.55) when compared to females (204.17 ± SD65.06) (CI 187.36, 220.97) and above the upper limit of normal reference range.The previous studies of NAFLD also indicated that men were more commonly affected than women 17 .Liver is a key site of action of insulin.Insulin resistance is a reproducible pathogenic factor in NAFLD pathogenesis and seems to be a common link between fatty liver and non insulin dependent diabetes mellitus 18   .The pathogenesis of type 2 diabetes involves both insulin resistance and defects in insulin secretion.Insulin resistance is an impairment of the physiological effects of insulin on concentration glucose.Regular glycemic control necessitates the pancreatic β cell sensing of glucose, production and liberation of insulin, binding of insulin to receptors with a subsequent commencement of a number of signaling proteins  23 .In hepatocytes, insulin resistance is related to hyperglycaemia and hyperinsulinaemia, formation of advanced glycation end-products, increased free fatty acids and their metabolites, oxidative stress and altered profiles of adipocytokines 2 .Accumulation of triglycerides could result in fatty liver because of increased uptake of free fatty acids and de novo synthesis exceeds hepatic lipid export and utilization by hepatocytes, which could potentially result from insulin resistance and alterations in lipid metabolism.The current study showed that there was the perceptible difference in mean values of triglycerides for cases of NALFD between diabetes (218.).NALFD leads to lowering of high-density lipoprotein cholesterol and formation of atherogenic small dense lowdensity lipoprotein particles leading to atherogenic plasma lipid profile and further increase the risk of cardiovascular disease 27 .There was mild variation in mean values of total cholesterol levels for cases of NALFD with diabetes (203.14 ± SD 43.11) (CI 197.05, 209.23) and non diabetic subjects (183.43 ± SD40.66) (CI 167.28, 187.81) (p=.0001).The current study demonstrates that total cholesterol and LDL levels were raised but not of much significance and well below the upper limit of reference range.Insulin also enhances cholesterol transport into arteriolar smooth muscle cells and increases endogenous lipid synthesis by these cells.Insulin also stimulates the proliferation of arteriolar smooth muscle cells, augments collagen synthesis in the vascular wall, increases the formation of and decreases the regression of lipid plaques, and stimulates the production of various growth factors which will lead to artherosclerosis 28 .Therefore, we conclude that non insulin dependent diabetes mellitus and dyslipidemia often coexist with NAFLD and the mortality due to cardiovascular risk possibly will compete with liver-related risk in dictating the final outcome.

Conclusion
Hepatic steatosis and non insulin dependent diabetes mellitus appears to be considerably allied.In addition, NALFD possibly represents an independent risk factor mainly due to atherogenic lipid profile which enhances the total cardiovascular risk further.Therefore, both hepatic steatosis and non insulin dependent diabetes mellitus

6 . 7 .
Nonalcoholic steatohepatitis(NASH), a histological subtype of NAFLD characterized by hepatocyte injury and inflammation is present in approximately 10% of patients with non-insulin diabetes mellitus and can progress to cirrhosis and liver failure.It is estimated to be the most common cause of cryptogenic cirrhosis at present Diabetes mellitus has a significant role in worsening of fibrosis.Overproduction of glucose, very low-density lipoproteins, triglycerides, Creactive protein and coagulation factors by the fatty liver may perhaps add to the excess risk of cardiovascular disease.Lack of knowledge regarding disease status, risk factors and reduced level of prior diagnosis leads to the high prevalence and mortality due to diabetes and NALFD among Nepalese population 8

Table 2 : Comparison of variables for cases of diabetes mellitus with NALFD and with no NALFD patients
) but well below the upper limit of normal reference range.The mean values of alanine and aspartate transaminases were in normal range in diabetes mellitus patients with NALFD or without NALFD.

Table 3 : Comparison of variables for cases of NALFD with DM patients and subjects with no family history of diabetes
* Statistically significant (p<0.05)Table

Table 4 : Comparison of variables for controls of NALFD with DM patients and subjects with no family history of diabetes
(called nonalcoholic steatohepatitis or NASH).NASH can progress to cirrhosis, decompensated liver disease, and hepatocellular carcinoma Nepal Journal of Epidemiology 2011;1 (2): 51-56 Copyright © 2010 INEA Published online by NepJOL-INASP 55 www.nepjol.info/index.php/NJEfibrosis