Elevated red blood cell distribution width is associated with morphometric vertebral fracture in community-dwelling older adults, independent of anemia, inflammation, and nutritional status: The Korean Urban Rural Elderly (KURE) study

Abstract

Elevated red blood cell distribution width (RDW), a simple measure of red blood cell size heterogeneity, has been associated with increased mortality and morbidity in the elderly population, which might reflect systemic inflammation and malnutrition. However, whether elevated RDW is associated with prevalent morphometric vertebral fracture (VF) in older adults has not been investigated. We examined 2127 individuals (mean age 71.7 years; women 66%) from a community-based cohort. VF was defined as ≥ 25% reduction in vertebral column height using the Genant semiquantitative method. Multiple VF was defined as the presence of VF at two or more sites. The prevalence of any VF and multiple VF was 14% and 4%, respectively, increasing from the lowest to the highest RDW tertiles (12-18% and 3-6%, p for trend < 0.05 for all). RDW was positively associated with age, body mass index (BMI), malnutrition, and high-sensitivity C-reactive protein (hsCRP), whereas it was negatively associated with albumin, hemoglobin, and ferritin levels. Elevated RDW was associated with any VF [adjusted odds ratio (aOR) 1.26; p = 0.008] and multiple VF (aOR 1.36; p = 0.010) after adjustment for covariates, including age, sex, BMI, hsCRP, malnutrition, self-reported previous fracture, falls, osteoporosis, and hemoglobin and ferritin levels. The association between elevated RDW and VF remained robust in subgroups with (aOR 1.39; p = 0.048) or without anemia (aOR 1.26; p = 0.030). Elevated RDW was associated with prevalent morphometric VF in community-dwelling elderly individuals, independent of anemia, inflammation, and nutritional status.