P0953 - Prevalence and Risk Factors of NAFLD, High-Risk NASH, and Fibrosis Among Lean US Adults

Markos Kalligeros, MD¹, Stephanos Vassilopoulos, MD², Athanasios Vassilopoulos, MD², Fadi Shehadeh, MSc³, Ingrid Lazaridou, MD², Eleftherios Mylonakis, MD, PhD³, Kittichai Promrat, MD², Jack R. Wands, MD^2
1Warren Alpert Medical School of Brown University, Providence, RI; ²Brown University, Providence, RI; ³Houston Methodist, Houston, TX

Introduction: Non-alcoholic fatty liver disease (NAFLD) is a growing public health concern worldwide. Early detection and management of modifiable risk factors are critical to mitigating its impact. This study aimed to investigate the prevalence and risk factors of NAFLD, high risk non-alcoholic steatohepatitis (NASH), and fibrosis among lean adults in the United States.

Methods: We used the latest National Health and Nutrition Examination Survey (NHANES) dataset from 2017-2020. Participants who were adults (≥18 years), have completed a transient elastography (TE) exam, and had BMI data were eligible for inclusion. We excluded individuals with BMI < 18.5 and >25kg/m2 (or >23 kg/m2 for Asians), those with heavy alcohol use ( >2 drinks/day for men, >1 for women), positive hepatitis C RNA or B surface antigen, and exposure to steatogenic drugs. Using controlled attenuation parameter (CAP) scores of ≥285 dB/m, we assessed the age-adjusted prevalence of lean NAFLD. To determine the age-adjusted prevalence of high-risk NASH and significant fibrosis, we used the FibroScan-AST (FAST) score (cut-offs 0.35) and vibration-controlled transient elastography (LSM ≥8kPa), respectively. Multivariate logistic regression was used to identify potential risk factors.

Results: From the 15,560 NHANES participants (2017-2020), 1,628 adults, classified as lean, were eligible for our analysis (Table 1). The age-adjusted prevalence of NAFLD among lean adults was found to be 6.30% (95% CI: 3.84-10.16%), with higher prevalence in adults aged 40 and above, and in certain ethnic groups (Fig.1). The prevalence of high-risk NASH (FAST > 0.35), was 1.29% (95% CI: 0.70-2.34%) among lean adults, higher in males, individuals over 60, and those with diabetes or hypertension. Significant fibrosis (LSM ≥8kPa) was prevalent in 4.35% (95% CI: 2.73-6.89%) of lean adults, and more common among older adults, NH Whites, and males. Older age, hypertension, diabetes, and dyslipidemia were associated with lean NAFLD. Hypertension was the only predictor of high-risk NASH (cut-off of 0.35) among lean adults. Additionally, lean adults with significant fibrosis (LSM ≥8.0 kPa) were more likely to be aged 60 years and over, and less likely to be of Asian descent.

Discussion: These findings suggest that the prevalence of NAFLD is of concern among lean individuals, particularly those aged 40 and older with metabolic comorbidities, while a targeted approach to screening and risk stratification for hepatic fibrosis upon lean NAFLD diagnosis is warranted.




Disclosures:


Markos Kalligeros, MD¹, Stephanos Vassilopoulos, MD², Athanasios Vassilopoulos, MD², Fadi Shehadeh, MSc³, Ingrid Lazaridou, MD², Eleftherios Mylonakis, MD, PhD³, Kittichai Promrat, MD², Jack R. Wands, MD². P0953 - Prevalence and Risk Factors of NAFLD, High-Risk NASH, and Fibrosis Among Lean US Adults, ACG 2023 Annual Scientific Meeting Abstracts. Vancouver, BC, Canada: American College of Gastroenterology.