The Correlation Analysis Between Obesity And Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease(NAFLD)is a clinical syndrome with main characteristics of diffuse hepatocellular bullae fatty change,caused by other specific damage factors except alcohol,and can be diagnosed by liver ultrasound.NAFLD has already become the most important cause of chronic liver disease,and had intertwined relationship with glucose and lipid metabolism disorder,diabetes,cardiovascular disease and metabolism related tumor.As the primary cause of chronic liver disease and abnormal liver enzymes in the western developed countries,NAFLD also became the second liver disease in China.The results from a Shanghai study showed that the prevalence of NAFLD is 15.4%in the general adults.Among the persons over 40 years,the prevalence of NAFLD is 51%?83%.Moreover,among obese patients,the prevalence of NAFLD is 47%?90%.In the present study,we analyzed the associations between obesity and NAFLD in healthy people.The main results are as follows:ObjectiveThe aim of the present study was to explore the prevalence and risk factors of nonalcoholic fatty liver disease in healthy people.Moreover,the associations between obesity and NAFLD were thoroughly investigated.Methods2970 people who were recruited from Annual health examination population from January 2013 to December 2013 in our study.The individuals with viral hepatitis,drug-induced hepatitis or autoimmune hepatitis were excluded.Additionally,the participants with excess alcohol consumption(the history of drinking or The amounnt of alcohol or ethanol:male?140g/week,female>70g/week)BMI<18.5kg/m2,severe infection,tumor,hyperthyroidism,hypothyroidism and Cushing disease were also excluded.All of participants were asked to provide informed consent.Demographic characteristics were collected with trained interviewer.According to the Chinese adult overweight and obesity prevention and control guidelines:BMI?24.0kg/m2 was defined as obesity or overweight;According to the standardisation of Asian announced by WHO:waist hip ratio?0.9(male)or>0.8(female)was defined as obesity?Age was divided based on the median.The diagnosis of NAFLD was based on the findings of hepatic ultrasound examination with a 3.5-MHz transducer(SoNoliNE Versa Plus,SIEMENS,Germany).According to the "Chinese Guideline on Diagnosis and Treatment of NAFLD",NAFLD was diagnosed based on the presence of at least 2 of the following 3 abnormal findings:diffuse increased echogenicity of liver relative to kidney,ultrasound beam attenuation,and poor visualization of intrahepatic structures.The ultrasonography was carried out by experienced radiologists who were blinded to the laboratory values of the examinees.Definition of nonalcoholic fatty liver disease and judgement of severity:according to the corresponding references,we defined Fatty liver B ultrasonic examination standard:The following three abdominal sonographic findings,a diagnosis of diffuse fatty liver:1)the area near field echo diffuse enhancement("bright liver"),the echo is stronger than the kidney;2)intrahepatic duct structure display is not clear;3)liver echo far field gradually weak.The database was established and checked by Epidata3.0 software.All statistical analyses were conducted using SAS 9.2 software.All tests were two-sided and differences were considered statistically significant if P values were<0.05.Data were expressed as the mean ? standard deviation(SD),median or percentage as suitable.Comparisons between groups were analyzed by t-test or Mann-Whitney U-test for measurement data and Chi-square test for enumeration data.Multivariate analyses using logistic regression,calculate OR and 95%CI.Result1.Among 2970 participants,514 persons were diagnosed as nonalcoholic fatty liver disease,including 1262 males(51.41%)and 75 females(14.56%)(P<0.001).After the adjustment of confounding factor,the prevalence of NAFLD in males is higher than those in female(P=0.040).There is no significant difference of NAFLD prevalence among different age groups.Of the participants with overweight/obesity,the prevalence of NAFLD was significant higher than those in the persons with<24 24.0kg/m2 of BMI(P<0.001).The prevalence of NAFLD was much higher in the group with high level of TC,high TG,low HDL,or high LDL,respectively.Additionally,the person with NAFLD had the higher levels of UA,PLT and CRE.2.Among 1337 NAFLD participants,331 persons were abnormal of liver function,including 313 males(24.80%)and 18 females(24.00%).The incidence of liver dysfunction in lower age was higher than higher age(P<0.001).Additionally,the incidence of liver dysfunction in the central obesity population was 25.77%and in the population with normal WHR was 21.69%.There is statistically significant difference between two groups(P=0.017).Moreover,the incidence of liver dysfunction in the population with abnormal level of TC,TG and LDL of liver dysfunction were higher than those in normal group.Among population with NAFLD,the people with liver dysfunction had higher level of UA than the participants with normal liver function(P=0.003).Conclusion1.The prevalence of nonalcoholic fatty liver disease in males is much higher than those in females.Overweight/obesity,central obesity or dyslipidemia had higher prevalence of NAFLD.2.In the population with NAFLD,the incidence of liver dysfunction in lower age group was higher than those in higher age group.Additionally,central obesity population and the population with abnormal level of TC,TG and LDL had a higher incidence of liver dysfunction.