Effects of Higher Red Cell Distribution Width Among Older Adults

Study authors found a significant association between greater variability of red blood cell (RBC) size and worse prognosis in hospitalized older adults (OAs).

With red cell distribution width (RDW) already a potential marker for poorer outcomes in several aging-related conditions and diseases, researchers tested how poor prognoses could be linked to greater variability of RBC size.

Data was collected between January 2013 and December 2017 from hospitalized OAs receiving care at Sutter Health in Northern California. During hospital admission RDW was measured and categorized with 1% intervals (≤13.9, 14.0–14.9, 15.0-15.9, 16.0-16.9, 17.0-17.9 and ≥18.0%).

According to study authors, the rate of in-hospital mortality was the primary outcome and secondary outcomes included length of hospital stay in days and 30-day readmission rate.

This study included 167,292 admissions from 94,617 patients, which resulted in an overall mortality rate of 6.3%. Researchers reported the RDW value increasing was linked to the rate of in-hospital mortality gradually increasing from 2.7% for the lowest RDW category to 12.2% in the highest category (P-trend < .001).

The rate of 30-day readmission also increased from increasing RDW categories resulting in 7.4% in the lowest group vs 15.8% in the highest group, P-trend < .001) with 12.5% being the overall 30-day readmission rate after discharge.

When compared to patients with lower RDW values admitted to the hospital for the same causes, patients with the highest RDW values at admission stated in the hospital 1.5-2 times longer.

“Greater variability of RBC size is significantly associated with worse prognosis in hospitalized elderly patients, indicating higher mortality, greater risk of early re-admission, and longer hospital stay days,” concluded study authors. “Risk stratification strategies for hospitalized elderly should include RDW value.”

Reference:
Min Kim K, Nerlekar R, Tranah GJ, Browner WS, Cummings SR. Higher red cell distribution width and poorer hospitalization-related outcomes in elderly patients. J Am Geriatr Soc. Published online May 4, 2022. doi:10.1111/jgs.1789