Gallstones (GS), commonly known as solid substances formed from cholesterol and bile pigments within the gallbladder, are linked to obesity and represent a significant public health concern. A recent study conducted using data from the National Health and Nutrition Examination Survey (NHANES) sheds light on the connection between relative fat mass (RFM) and the prevalence of gallstones, emphasizing RFM's predictive abilities compared to traditional measures like body mass index (BMI).
Published on March 17, 2025, the study analyzed data collected between 2017 and March 2020, incorporating 7978 adults aged 20 years and older, of whom 828 reported having gallstones. The researchers aimed to evaluate the relationship between RFM—an indicator reflecting fat distribution and composition—and the risk factors associated with gallstones, including the age at which individuals undergo their first surgery for this condition.
The study findings revealed compelling outcomes. For every 1-unit increase in RFM, there was a corresponding 9% increase in the prevalence of gallstones, with the calculated odds ratio being 1.09 (95% confidence interval: 1.07 – 1.11). Notably, the threshold for RFM impacting gallstone prevalence was identified as 40.99, indicating the significance of managing abdominal obesity.
Further subgroup analyses illustrated variations based on demographic groups. Specifically, men experienced a 6% increase (odds ratio: 1.06, 95% CI: 1.02, 1.09) for every unit rise in RFM, whereas women experienced an increase of 11% (odds ratio: 1.11, 95% CI: 1.09, 1.13). Among participants with diabetes, each unit increase of RFM correlated with a 6% increase (odds ratio: 1.06, 95% CI: 1.02, 1.11) whereas non-diabetic participants had a 10% increase (odds ratio: 1.10, 95% CI: 1.08, 1.12), emphasizing the intersection of obesity and chronic conditions.
RFM emerged as a stronger predictor for gallstone risk with a predictive value of 69.66% (95% CI: 67.78 – 71.53), surpassing the predictive capability of BMI and waist circumference which stood at 63.96% and 63.99% respectively. These statistics highlight the importance of utilizing RFM as a more sensitive measure for assessing obesity-related health risks, particularly for gallstones.
The study also recorded associations concerning the age patients underwent their first gallstone surgery. It suggested each 1-unit increase in RFM led to patients being 0.45 years younger at the time of surgery, adjusting to 0.19 years when covariates were accounted for—indicating the potential impetus for earlier surgical intervention linked to higher RFM levels. The threshold for RFM affecting age at surgery was documented at 30.99.
Gallstones are more prevalent among populations grappling with obesity, particularly when abdominal fat is involved. While various risk factors contribute to gallstone development—such as dietary habits, genetic predispositions, and metabolic health—the current study cements RFM as a significant indicator of risk tied to increased fat mass.
The research found substantial support for the hypothesis; RFM is not only linked with gallstone prevalence but stands as a formidable tool for predicting risk, implying it could complement traditional metrics like BMI for improved health screening. The authors of the article concluded by emphasizing the necessity for prospective studies to explore RFM's efficacy across diverse populations, which could help refine preventative measures for gallstone disease.
This investigation reaffirms the multifaceted relationship between obesity metrics and the onset of gallbladder conditions, supporting the case for adopting more comprehensive obesity assessments to curtail the growing public health issue of gallstones.
