Kidney Week

Abstract: TH-PO916

Association of Hemoglobin Level with Mortality and Its Effect Modifiers in Patients Undergoing Maintenance Hemodialysis: A Nationwide Cohort Study

Session Information

• Anemia and Iron Metabolism
  October 24, 2024 | Location: Exhibit Hall, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Anemia and Iron Metabolism

• 200 Anemia and Iron Metabolism

Authors

• Kosugi, Takaaki, Department of Nephrology, Nara Medical University, Kashihara, Nara, Japan

Takaaki Kosugi, MD, PhD

• Hasegawa, Takeshi, Institute of Clinical Epidemiology, Showa University, Tokyo, Japan

Takeshi Hasegawa, MD, PhD, MPH

• Imaizumi, Takahiro, Department of Advanced Medicine, Nagoya University Hospital, Nagoya, Japan

Takahiro Imaizumi, MD, PhD

• Nishiwaki, Hiroki, Division of Nephrology, Department of Medicine, Showa University Fujigaoka Hospital, Yokohama, Japan

Hiroki Nishiwaki, MD, PhD, MPH

• Honda, Hirokazu, Division of Nephrology, Department of Medicine, School of Medicine, Showa University, Tokyo, Japan

Hirokazu Honda, MD, PhD

• Ito, Yasuhiko, Department of Nephrology and Rheumatology, Aichi Medical University, Nagakute, Japan

Yasuhiko Ito, MD, PhD

• Tsuruya, Kazuhiko, Department of Nephrology, Nara Medical University, Kashihara, Nara, Japan

Kazuhiko Tsuruya, MD, PhD

• Abe, Masanori, Division of Nephrology, Hypertension and Endocrinology, Department of Internal Medicine, Nihon University School of Medicine, Tokyo, Japan

Masanori Abe, MD, PhD

• Hanafusa, Norio, Department of Blood Purification, Tokyo Women's Medical University, Tokyo, Japan

Norio Hanafusa, MD, PhD

• Kuragano, Takahiro, Division of Kidney and Dialysis, Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya, Japan

Takahiro Kuragano, PhD

Background

The optimal range of hemoglobin (Hb) levels in patients on hemodialysis (HD) remains controversial. This study aimed to investigate the association between Hb levels and mortality in patients on HD, and to explore the potential factors modifying this association using the latest nationwide database in Japan.

Methods

This observational study utilized a nationwide database from the Japanese Renal Data Registry spanning from 2019 to 2021. This study included 265,779 patients who underwent HD thrice a week. The exposure of interest was the Hb level, which was categorized into six groups: <9.0, 9.0–9.9, 10.0–10.9, 11.0–11.9, 12.0–12.9, and ≥13.0 g/dL. The primary outcome was all-cause mortality. A multivariable Cox regression analysis was performed. The nonlinear relationship between Hb levels and outcomes was investigated using restricted cubic spline analysis. Subgroup analysis was performed to explore the potential factors modifying the association between Hb levels and all-cause mortality. Missing values were imputed using multiple imputations by chained equations.

Results

During a median follow-up period of 24 months, 45,734 patients died. Compared to the reference Hb category of 10–10.9 g/dL, the risk of all-cause mortality was higher in the Hb categories of <9.0, 9.0–9.9, and ≥13 g/dL with the adjusted hazard ratios (95% confidence intervals) of 1.24 (1.20–1.29), 1.09 (1.06–1.12), and 1.19 (1.14–1.25), respectively. Restricted cubic spline analysis also showed a U-shaped relationship between Hb level and mortality. The subgroup analysis indicated that the Hb category of 12.0–12.9 g/dL was associated with increased mortality risk in patients on dialysis for ≥10 years and those with a history of cerebral infarction.

Conclusion

Hb levels of <10.0 and ≥13.0 g/dL were significantly associated with an increased risk of mortality compared with an Hb level of 10.0–10.9 g/dL in patients undergoing HD. An Hb level of ≥12.0 g/dL was also associated with an increased risk in patients on dialysis for ≥10 years and those with a history of cerebral infarction.