The association of cadmium and lead exposures with red cell distribution width

• Published in: PloS one 2021-01, Vol.16 (1), p.e0245173
• Main Authors: Peters, Junenette L, Perry, Melissa J, McNeely, Eileen, Wright, Robert O, Heiger-Bernays, Wendy, Weuve, Jennifer
• Format: Article
• Language: English
• Subjects: Alcohol use; Anemia; Biology and Life Sciences; Blood; Blood cells; Body mass; Body mass index; Body size; Bone marrow; Cadmium; Carrying capacity; Chronology; Cotinine; Editing; Environmental health; Epidemiology; Erythrocytes; Erythropoiesis; Ethnicity; Exposure; Funding; Health aspects; Heavy metals; Hemoglobin; Iron; Laboratories; Lead; Lead content; Lead poisoning; Medicine and Health Sciences; Metals; Minority & ethnic groups; Mortality; Occupational health; Oxidative stress; Oxygen; Physical Sciences; Physiological aspects; Poverty; Public health; Regression analysis; Regression models; Reticulocytes; Reviews; Severe acute respiratory syndrome coronavirus 2; Social Sciences; Statistical analysis; Variables
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0245173

Elevated red blood cell distribution width (RDW), traditionally an indicator of anemia, has now been recognized as a risk marker for cardiovascular disease incidence and mortality. Experimental and acute exposure studies suggest that cadmium and lead individually affect red blood cell production; however, associations between environmental exposures and RDW have not been explored. We evaluated relationships of environmental cadmium and lead exposures to RDW. We used data from 24,607 participants aged ≥20 years in the National Health and Nutrition Examination Survey (2003-2016) with information on blood concentrations of cadmium and lead, RDW and socio-demographic factors. In models adjusted for age, sex, race/ethnicity, education, poverty income ratio, BMI, alcohol consumption, smoking status and serum cotinine, RDW was increasingly elevated across progressively higher quartiles of blood cadmium concentration. A doubling of cadmium concentration was associated with 0.16 higher RDW (95% CI: 0.14, 0.18) and a doubling of lead concentration with 0.04 higher RDW (95% CI: 0.01, 0.06). Also, higher cadmium and lead concentrations were associated with increased odds of high RDW (RDW>14.8%). The associations were more pronounced in women and those with low-to-normal mean corpuscular volume (MCV) and held even after controlling for iron, folate or vitamin B12 deficiencies. In analysis including both metals, cadmium remained associated with RDW, whereas the corresponding association for lead was substantially attenuated. In this general population sample, blood cadmium and lead exposures were positively associated with RDW. The associations may indicate hemolytic or erythropoietic mechanisms by which exposure increases mortality risk.