ASN's Mission

To create a world without kidney diseases, the ASN Alliance for Kidney Health elevates care by educating and informing, driving breakthroughs and innovation, and advocating for policies that create transformative changes in kidney medicine throughout the world.

learn more

Contact ASN

1401 H St, NW, Ste 900, Washington, DC 20005

email@asn-online.org

202-640-4660

The Latest on Twitter

Kidney Week

Abstract: TH-PO681

Association of Iron Therapy With Incidence of 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
  • Paul, Shejuti, The University of Tennessee Health Science Center, Memphis, Tennessee, United States
  • Sumida, Keiichi, The University of Tennessee Health Science Center, Memphis, Tennessee, United States
  • Thomas, Fridtjof, The University of Tennessee Health Science Center, Memphis, Tennessee, United States
  • Surbhi, Satya, The University of Tennessee Health Science Center, Memphis, Tennessee, United States
  • Naser, Abu Mohd, The University of Memphis, Memphis, Tennessee, United States
  • Streja, Elani, University of California Irvine, Irvine, California, United States
  • Rhee, Connie, University of California Irvine, Irvine, California, United States
  • Kalantar-Zadeh, Kamyar, University of California Irvine, Irvine, California, United States
  • Kovesdy, Csaba P., The University of Tennessee Health Science Center, Memphis, Tennessee, United States
Background

Iron replacement therapy (IRT) is effective in treating iron deficiency, but there are concerns about its effects on kidney function due to the impact of oral iron on the gut microbiome and to the oxidative stress caused by intravenous iron. We aimed to investigate the association of IRT with the incidence of new onset chronic kidney disease.

Methods

We identified 210,209 patients with normal eGFR and no albuminuria (N=51,448 on IRT and N=158,761 not on IRT) from 2004-2018 in a large national cohort of US Veterans. Of the patients receiving IRT, 48,946 (95%) received oral iron only, 63 (0.1%) received intravenous iron only, and 2,439 (4.7%) received both modalities. We used clinical trial emulation methods including propensity score (PS) matching to examine the association of IRT with the incidence of eGFR <60 ml/min/1.73m2 and with incident urine albumin creatinine ratio (UACR) >30 mg/gm (both defined as two values at least 90 days apart) using competing risk regression.

Results

In the PS matched cohort of 64,446 patients (32,223 on IRT and 32,223 not on IRT) characteristics were well matched. The overall mean (SD) age was 66±13 years, 92% were male, 74% were white, and the baseline eGFR, hemoglobin and ferritin levels were 86±16 ml/min/1.73m2, 12±1.6 g/dL and 76 (25th-75th pctl 26-188) µg/L, respectively. There were 10,078 cases of incident eGFR <60 (event rate 37/1000PY; 95% CI 37-38) and 7,632 cases of incident albuminuria (28/1000PY; 95% CI 27-28) over a median follow up of 3.0 years. IRT was associated with a higher risk of incident eGFR <60 (subhazard ratio, 1.23; 95% CI 1.19-1.28) and a higher risk of albuminuria (1.12; 1.07-1.18). (Table)

Conclusion

In this large national cohort of patients with normal kidney function, IRT was associated with modestly higher risks of incident CKD and albuminuria.

Association of Iron Replacement Therapy with Incidence of CKD
 Incident eGFR <60 ml/min/1.73m2Incident UACR >30 mg/gm
Event rate per 1000PY (95%CI)Subhazard ratio (95%CI)P valueEvent rate per 1000PY (95%CI)Hazard ratio (95%CI)P value
No Iron therapy (N=32,223)34 (33,35)Reference<0.00126 (25, 27)Reference<0.001
Iron therapy (N=32,223)41 (40,42)1.23 (1.19, 1.28)29 (28, 30)1.12 (1.07, 1.18)

Funding

  • Veterans Affairs Support