Abstract
BACKGROUND: The relationship between metabolic associated fatty liver disease (MAFLD) and thyroid nodule (TN) is unknown, despite the overweight & obese individuals showed a greater risk of nonalcoholic fatty liver disease(NAFLD) and thyroid cancer compared to the normal Body mass index(BMI) individuals. This is a cross-sectional study examining the association between TN and MAFLD in healthy Chinese population undergoing simultaneous abdominal and thyroid ultrasonography. METHODS: A total of 78,077 healthy individuals with complete biochemical, thyroid and liver ultrasonography data from the Quality Control Center of Health Examination in Chongqing, China were included in the study. TNs were classified into malignancy risk levels of 5 different categories in accordance with Thyroid Imaging Reporting and Data System(TI-RADS). We investigated the association between MAFLD and TNs by binomial logistic regression analyses, and multinomial logistic regression analyses were performed to test the independence of associations between TNs or different TI-RADS categories of TNs and MAFLD.This study was designed and reported in accordance with the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guidelines to ensure transparency and completeness in reporting observational research. RESULTS: The prevalence of TN, MAFLD and combined TN with MAFLD were 30.4% (female: 36.7%, male: 26%), 26.9% (female: 13.4%, male: 36.4%) and 8.8% (female: 10.1%, male: 6.8%), respectively. The males with MAFLD had a higher risk of TN after adjustment for age, gender, blood pressure and some hepatic and renal function indicators, males with MAFLD had a higher risk of TN (OR = 1.108,95%CI: 1.054–1.165, P < 0.001)and TN of TI-RADS ≥ 4A (OR = 1.231,95%CI: 1.158–1.308, P < 0.001) compared to males without MAFLD; Furthermore, with stratification on the basis of BMI, only non-obese men with MAFLD had a higher risk of TN (OR = 1.100,95%CI: 1.016–1.191, P = 0.019) and TN of TI-RADS ≥ 4A (OR = 1.213, 95%CI: 1.099–1.340, P < 0.001). However, no statistical risk of TN or TN of TI-RADS ≥ 4A was observed in females with MAFLD. CONCLUSION: The prevalence of MAFLD and TN is high in Chinese healthy population with difference between males and females; The association between TN or TN of TI-RADS ≥ 4A and MAFLD is only observed in non-obese males.