Prevalence of nonalcoholic fatty liver disease (NAFLD) diagnosed by controlled attenuation parameter with transient elastography in subjects with and without metabolic syndrome

Abstract

Background : Non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disease worldwide. The prevalence of NAFLD in the adult ranges from 20% to 40%. Currently, controlled attenuation parameter with transient elastography (CAP-TE) is an accepted standard of diagnostic tool for grading the severity of liver steatosis and liver fibrosis with high accuracy.

Objectives : To compare the prevalence of NAFLD and to identify risk factors of significant steatosis in participants with and without metabolic syndrome (mets) by CAP-TE.

Methods We conducted a study of 161 subjects who worked at King Chulalongkorn Memorial Hospital, from March to October 2016. We collected age, sex, weight, height, waist and hip circumference, comorbidities and the medical
history of the risks of liver diseases including history of alcohol consumption, chronic viral hepatitis B and hepatitis C infection by using questionnaire. The laboratory tests including fasting plasma glucose, HDL-C, triglyceride, ALT, HBsAg, AntiHCV were conducted. CAP-TE was used to measure the degree of liver steatosis and fibrosis by experienced operator (KS). The result of liver stiffness result was reported in kPa, using the median value of 10 measurements whereas the degrees of fatty liver were reported in dB/m. The definition of NAFLD was the presence of liver fat >10%, whereas liver fat of >33% is classified as significant steatosis and >66% is classified as severe fatty liver.

Results : From 161 subjects, 99 of them (61.5%) had NAFLD. The prevalence of NAFLD in subjects with mets was significantly higher than those without mets (97% vs. 52%, P <0.001). The risk factors of significant steatosis
were BMI 25 kg/m² (OR 12.4, 95% CI 5.8 - 26.4), elevated waist circumference (OR 11.0, 95% CI 4.9 - 24.4), hypertension (OR 5.5, 95% CI 1.9 - 15.9), impaired fasting glucose (OR 3.3, 95% CI 1.4 - 7.7), high triglyceride level (OR 8.7, 95% CI 3.1 - 24.6), low level of HDL-C (OR 3.5, 95% CI 1.7 - 7.1) and presence of mets (OR 26.6, 95% CI 7.6 - 92.6). The significant risk factors from multivariate analysis were BMI  25 kg/m² (OR 3.6, 95% CI 1.3 - 9.9, P = 0.014) and high ALT (OR 1.05, 95% CI 1.00 - 1.09, P = 0.03). Additionally, the grading severity of significant fibrosis
of at least 7 kPa (>F2) of the total cohort was 3.8% and the severe fatty liver of at least 66% (>296 dB/m) was 19.3%.

Conclusion : The prevalence of NAFLD in the subjects with metabolic syndrome was significantly higher than those without metabolic syndrome. Additionally, this cohort showed a high prevalence of NAFLD (61.5%) and significant
liver fibrosis of 3.8%.