Waist Size Proves Key to Assessing Liver Health

Introduction

Metabolic dysfunction-associated steatotic liver disease (MASLD) has become a prevalent liver condition affecting roughly one in three adults worldwide. Its progression to more severe liver disorders such as metabolic dysfunction-associated steatohepatitis (MASH) and increased liver stiffness, which can signal fibrosis, poses significant health risks. While body mass index (BMI) is commonly used to estimate fat mass, it does not adequately reflect fat distribution, particularly visceral fat linked to liver disease. This article reviews recent research highlighting waist circumference as the most reliable predictor of MASLD risk and its complications across diverse adult populations, including those with diabetes and multiple metabolic disorders.

Methodology

Researchers conducted a comprehensive analysis of survey data collected from 2017 to 2023 involving 11,579 adults with detailed liver health assessments and anthropometric measurements. The study examined multiple body composition markers, including height, weight, waist circumference, hip circumference, body adiposity index, BMI, body roundness index, fat mass, waist-to-hip ratio, waist-to-height ratio, waist-adjusted BMI, and weight-adjusted waist index. MASLD was diagnosed based on a controlled attenuation parameter (CAP) of at least 275 dB/m with metabolic dysfunction. MASH was identified using a FibroScan aspartate aminotransferase score of 0.35 or higher, and increased liver stiffness was defined by liver stiffness measurements equal to or exceeding 8 kPa.

Key Findings

Among the participants (median age 51 years; 47% men), 40.9% had MASLD, 6.5% were diagnosed with MASH, and 9.9% showed increased liver stiffness. Waist circumference emerged as the strongest predictor for MASLD, surpassing BMI and waist-to-height ratio, with an area under the curve (AUC) of 0.82. It also predicted increased liver stiffness (AUC 0.75) and MASH (AUC 0.73) more effectively than other body composition indices. These trends remained consistent in subgroups with diabetes and multiple metabolic comorbidities.

Sex-stratified analysis revealed that waist circumference-based markers, including body roundness index and waist-to-height ratio, were the top predictors in both men and women, with waist circumference alone closely following. The relationship between waist circumference and MASLD risk was nonlinear, showing risk stabilization slightly above 100 cm. In contrast, MASH risk increased linearly across all waist sizes, while elevated liver stiffness risk rose sharply only beyond a waist circumference of 100 cm.

Clinical Implications

The findings underscore the importance of waist circumference measurement in clinical practice as a simple, non-invasive, and effective tool to identify individuals at risk for MASLD, MASH, and liver fibrosis. The authors recommend prioritizing waist circumference assessments, especially for patients who do not present overt obesity but may still have significant visceral fat accumulation.

Conclusion

Waist circumference is a critical metric for assessing metabolic liver health risk, outperforming traditional measures like BMI. Its use can facilitate early detection and intervention in MASLD and its more severe forms, potentially improving patient outcomes. Health professionals are encouraged to incorporate waist circumference monitoring into routine evaluations for adults at risk of metabolic liver diseases.

Reference

van Kleef LA, Michel M, Savas M, Pustjens J, van de Laar R, Koehler E, van Rossum EFC, Janssen HLA, Schattenberg JM, Brouwer WP. A comparison of the predictive value of 12 body composition markers for MASLD, at-risk MASH and increased liver stiffness in a general population setting. Am J Gastroenterol. 2025 Jul 23. doi: 10.14309/ajg.0000000000003657. Epub ahead of print. PMID: 40699281.