# The Relationship of the Red Cell Distribution Width-to-Albumin Ratio and Other Inflammatory Markers With Cataracts: An Analysis of the NHANES Population

## TL;DR

This study shows that a blood test measuring red cell distribution width-to-albumin ratio can help predict cataract risk, especially in older adults.

## Contribution

RAR is shown to be a better predictor of cataracts than other inflammatory markers like neutrophil-to-lymphocyte ratio.

## Key findings

- Higher RAR levels are positively linked to increased cataract risk with an inverted U-shaped relationship.
- RAR has a better predictive ability (AUC 0.601) compared to other inflammatory markers for cataracts.
- An RAR threshold of >3.025 may identify high-risk individuals aged ≥50 years.

## Abstract

This study aimed to explore the relationship between the ratio of red cell distribution width to albumin (RAR) and cataract risk.

We analyzed 13,031 participants from the National Health and Nutrition Examination Survey 1999–2008. The RAR was evaluated as a composite marker of systemic inflammation and nutritional status. Multivariable logistic regression and receiver operating characteristic analysis were used to assess the association and discriminative ability of the RAR compared with other inflammatory markers.

The findings indicated a positive link between higher RAR levels and the risk of cataracts, with a nonlinear relationship exhibiting an inverted U shape. Individuals in the higher quartiles of the RAR were observed to have a significantly greater risk of cataracts compared with those in the lower quartiles. The area under the curve for the RAR in predicting cataracts was determined to be 0.601, suggesting a greater predictive capability compared with other inflammatory markers, including the neutrophil-to-lymphocyte ratio and the Systemic Immune Inflammation Index.

A higher RAR is significantly associated with moderate-to-severe cataracts. An RAR threshold of >3.025 may serve as a practical metric for identifying high-risk individuals, particularly among those aged ≥50 years.

As a routine and cost-effective marker of inflammation and nutrition, the red cell distribution width-to-albumin ratio offers a practical tool to support cataract risk stratification and early identification in primary care settings.