Association between reduced hemoglobin-to-red cell distribution width ratio and elevated cardiovascular mortality in patients with diabetes: Insights from the National Health and Nutrition Examination Study, 1999-2018

Abstract

Objective: The purpose of this research was to examine the relationship between the hemoglobin-to-red blood cell distribution width ratio (HRR) and cardiovascular disease (CVD)-related mortality in people who have diabetes.

Methods: Data derived from the National Health and Nutrition Examination Survey (NHANES), between the years 1999 to 2018, were meticulously analyzed. Mortality data, encompassing events until December 31, 2019, were systematically collected. A comprehensive group comprising of 8,732 participants were subjected to scrutiny, and subsequently, classified into four distinct groups predicated upon quartiles of baseline HRR levels: Q1 (n = 2,183), Q2 (n = 2,181), Q3 (n = 2,185), and Q4 (n = 2,183). The correlation between HRR and CVD-related mortality was examined through the use of survival curves and Cox proportional hazard regression models, the latter incorporating weights as advised by NHANES.

Results: Among the 8,732 participants in the study cohort, CVD-related mortality was identified in 710 cases. The Kaplan-Meier analysis demonstrated a significant association, indicating that a decreased HRR was correlated with a reduction in survival in cases with CVD. Both univariate and multivariable Cox proportional hazard regression analyses consistently indicated that patients exhibiting a lower HRR exhibited a markedly elevated risk of CVD-related mortality in comparison to those with higher HRR. Notably, the correlation between HRR and decreasing CVD-related mortality was discerned to be non-linear.

Conclusion: In patients with diabetes, a decreased HRR was associated with an increased risk of CVD-related mortality.

Keywords: Cardiovascular disease-related mortality; NHANES; Red cell distribution width; diabetes mellitus; hemoglobin.