Kidney Week

Abstract: TH-PO682

Association of Parenteral vs. Oral Iron Therapy With Incident CKD

Session Information

• Anemia and Iron Metabolism
  November 03, 2022 | Location: Exhibit Hall, Orange County Convention Center‚ West Building
  Abstract Time: 10:00 AM - 12:00 PM

Category: Anemia and Iron Metabolism

• 200 Anemia and Iron Metabolism

Authors

• Shrestha, Prabin, The University of Tennessee Health Science Center, Memphis, Tennessee, United States

Prabin Shrestha,

• Paul, Shejuti, The University of Tennessee Health Science Center, Memphis, Tennessee, United States

Shejuti Paul,

• Sumida, Keiichi, The University of Tennessee Health Science Center, Memphis, Tennessee, United States

Keiichi Sumida,

• Thomas, Fridtjof, The University of Tennessee Health Science Center, Memphis, Tennessee, United States

Fridtjof Thomas,

• Surbhi, Satya, The University of Tennessee Health Science Center, Memphis, Tennessee, United States

Satya Surbhi,

• Naser, Abu Mohd, The University of Memphis, Memphis, Tennessee, United States

Abu Mohd Naser,

• Streja, Elani, University of California Irvine, Irvine, California, United States

Elani Streja,

• Rhee, Connie, University of California Irvine, Irvine, California, United States

Connie Rhee,

• Kalantar-Zadeh, Kamyar, University of California Irvine, Irvine, California, United States

Kamyar Kalantar-Zadeh,

• Kovesdy, Csaba P., VA Memphis Medical Center, Memphis, Tennessee, United States

Csaba P. Kovesdy,

Background

Parenteral (IV) iron is effective in treating iron deficiency, but there are concerns about its potential nephrotoxicity. However, little is known about the long-term comparative renal safety of oral vs IV iron in patients with normal kidney function. We aimed to investigate the association of oral vs IV iron with the incidence of new onset chronic kidney disease (CKD).

Methods

We identified 94,931 incident new users of iron replacement therapy (N=91,945 on oral and 2,986 on IV iron) from 2004-2018 in a large national cohort of US Veterans. We used clinical trial emulation methods including propensity score (PS) matching to account for differences in key baseline characteristics and limited the cohort to patients with eGFR >60 ml/mi/1.73m² and urine albumin creatinine ratio (UACR) <30 mg/g. We examined the association of oral vs IV iron with the incidence of eGFR <60 ml/min/1.73m² and UACR >30 mg/g (both defined as two values at least 90 days apart) using competing risk regression.

Results

In the PS matched cohort there were 1,029 patients on oral and 1,043 on IV iron with eGFR ≥60 ml/min/1.73m² and UACR <30 mg/g at baseline. Their characteristics were well balanced, with an overall mean (SD) age of 66±12 years, 92% male, 75% white, and baseline eGFR, hemoglobin and ferritin levels of 90±18 ml/min/1.73m², 9.7±1.8 g/dL and 34 (25^th-75^th pctl: 11-190) µg/L, respectively. There were 370 cases of incident GFR <60 (event rate 58/1000PY; 95% CI 53-65) and 251 cases of incident albuminuria (39/1000PY; 95% CI 34-44) over a median follow-up of 1.8 years. IV (vs oral) iron therapy was associated with similar risk of incident eGFR <60 (subhazard ratio (95%CI): 1.12 (0.91-1.37), p=0.27) and incident albuminuria (1.01 (0.79-1.29), p=0.9) (Table).

Conclusion

In this large national cohort of patients with baseline normal kidney function and no proteinuria, IV iron therapy was not associated with higher risk of incident CKD when compared to oral iron.

Association of Parenteral vs. Oral Iron Therapy with Risk of Incident Chronic Kidney Disease

Funding

• Veterans Affairs Support