Study Explores Fatty Liver Disease and Liver Function in US Adults
Washington D.C. – A recent study, utilizing data from the National Health and Nutrition Examination Survey (NHANES) spanning from 2003 to 2018, has shed light on the relationship between fatty liver disease and overall liver function in a diverse US population. The research, which received ethical approval from the Centers for Disease Control and Prevention (CDC) Institutional Review Board, focused on identifying and categorizing individuals with Metabolic-Associated Fatty Liver Disease (MAFLD) and assessing their liver health through the Albumin-Bilirubin (ALBI) score.
The study meticulously selected participants, excluding those with incomplete data crucial for the ALBI score or MAFLD diagnosis. To ensure data integrity and account for any missing information, researchers employed a sophisticated multiple imputation technique. This method generated five complete datasets, preserving the intricate relationships between various analytical variables.
Understanding the ALBI Score and MAFLD Classification
The ALBI score, a key metric in this study, is calculated using a formula that incorporates bilirubin and albumin levels in the blood. Lower, more negative ALBI scores indicate better liver function. The researchers adapted the traditional ALBI grading system into three tertile groups (Q1, Q2, and Q3) for more nuanced analysis within their cohort.
Metabolic-Associated Fatty Liver Disease (MAFLD) was identified using the US-FLI, a calculation that considers various physiological markers including ethnicity, age, liver enzymes (gamma-glutamyl transferase), waist circumference, insulin, and glucose levels. A US-FLI score of 30 or higher, coupled with the absence of other established causes of chronic liver disease such as viral hepatitis or significant alcohol consumption, was used to diagnose MAFLD.
Participant Demographics and Health Factors
The study participants were stratified into distinct age groups: young adults (20-39 years), middle-aged adults (40-59 years), and older adults (60 years and above). Racial and ethnic categories included non-Hispanic White, non-Hispanic Black, Mexican American, and other self-identified groups. Educational attainment was categorized into incomplete secondary education, completion of secondary education, and postsecondary education. Socioeconomic status was assessed using the poverty-income ratio (PIR), with participants divided into low-income (PIR ≤ 1.5), middle-income (1.5 < PIR ≤ 3.0), and high-income (PIR > 3.0) brackets. Tobacco exposure history was also documented, classifying individuals as lifetime nonsmokers.
Further details regarding the specific inclusion and exclusion criteria and a comprehensive flowchart illustrating the selection of the study population are provided in Figure 1. This research provides valuable insights into the prevalence and characteristics of fatty liver disease within the US population, contributing to our understanding of liver health and related risk factors.