The Red Cell Distribution Width Ratio is Positively Associated with Non-Alcoholic Fatty Liver Disease: A Cross-Sectional Study Using NHANES Data

Introduction: The global incidence of non-alcoholic fatty liver disease (NAFLD) is increasing, imposing a great public health concern. It remains unclear how hemoglobin and the red blood cell distribution width ratio (HRR) relate to NAFLD; therefore, this investigation aimed to elucidate the association between the HRR and NAFLD. Methods: This cross-sectional study analyzed data from the National Health and Nutrition Examination Survey (NHANES) conducted between 2005 and 2018, involving 2,720 participants. The relationship between the HRR and the likelihood of NAFLD was evaluated using weighted logistic regression, restricted cubic spline curves, and subgroup analyses. The XGBoost model was utilized to forecast the risk of NAFLD and explore its potential mechanisms. Results: Among the 2,720 participants, 281 had NAFLD. After adjusting for age, race, smoking habits, hypertension presence, and diabetes diagnosis, the odds ratio (OR) for patients with NAFLD having an elevated HRR was calculated at 1.283, revealing the HRR as an independent risk factor for NAFLD. Further quartile analyses showed that an increased HRR correlated with a heightened risk of developing NAFLD. The XGBoost model corroborated the significance of the HRR in NAFLD progression. Subgroup analyses revealed correlations between the HRR and sex, race, body mass index, hypertension diagnosis, diabetes status, educational attainment, and family poverty income ratio. Additionally, a heightened HRR was linked to an elevated red blood cell count and high levels of cholesterol, low-density lipoprotein cholesterol, alanine aminotransferase, and total bilirubin, while being associated with a reducedblood urea nitrogen level. Conclusion: The results of this study indicate that the HRR is a crucial risk factor for NAFLD, which could be valuable in clinical settings. Future large-scale prospective studies are warranted to deepen the understanding of the relationship and mechanisms connecting HRR and NAFLD, potentially aiding in early diagnosis and tailored treatment strategies for NAFLD.