Prevalence, Correlates, and Outcomes of Absolute and Functional Iron Deficiency Anemia in Peritoneal Dialysis: A...

Iron deficiency anemia (IDA) correlates with an increased risk of adverse cardiovascular outcomes and mortality in chronic kidney disease. Its prevalence and prognostic implications in peritoneal dialysis (PD) populations remain underexplored.

This single-center cohort included 2,121 PD patients (2009-2023) followed until 2024 and stratified by iron deficiency (ID) status: non-ID anemia, absolute IDA (transferrin saturation [TSAT] <20% + ferritin <100 ng/mL), functional IDA (FID, TSAT <20% + ferritin 100-500 ng/mL), and high-risk FID (TSAT <20% + ferritin >500 ng/mL). Multivariable logistic regression and Cox models were employed.

The cohort (59.5% male; mean age 45.2 ± 14.3 years) demonstrated 72.4% anemia prevalence, comprising non-ID anemia (29.7%), absolute IDA (22.9%), functional IDA (16.4%), and high-risk FID (3.4%). Independent anemia associated factors included female sex (odds ratio [OR] = 1.29), reduced estimated glomerular filtration rate (OR = 0.93), hypoalbuminemia (OR = 2.19), and elevated high-sensitivity C-reactive protein (OR = 1.68). During a median follow-up of 1,389 ± 941 days, 425 patients (20.0%) died, including 220 (10.4%) from cardiovascular events. High-risk FID independently predicted all-cause mortality (hazard ratio= 1.94, P= .005) and cardiovascular mortality (hazard ratio= 1.98, P= .037) after full adjustment.

Functional IDA with ferritin >500 ng/mL exhibits distinct clinical features and is strongly related to high mortality in PD patients, underscoring urgent need for targeted therapeutic strategies.