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Abstract: TH-PO263

The Association of the Difference in Hemoglobin Levels Before and After Hemodialysis with the Risk of 1-Year Mortality in Patients Undergoing Hemodialysis: Results from the Japanese Renal Data Registry

Session Information

Category: Anemia and Iron Metabolism

  • 202 Anemia and Iron Metabolism: Clinical


  • Nishiwaki, Hiroki, Showa University Fujigaoka Hospital, Yokohama, Japan
  • Hasegawa, Takeshi, Showa University Fujigaoka Hospital, Yokohama, Japan
  • Hamano, Takayuki, Osaka University Graduate School of Medicine, Suita, OSAKA-FU, Japan
  • Masakane, Ikuto, Honcho-Yabuki Clinic, Yamagata, Japan

Group or Team Name

  • The Japanese Society for Dialysis Therapy, Committee of Renal Data Registry

Few clinical studies have directly examined the associations of hemoglobin (Hb) levels after hemodialysis (HD) and of the difference in Hb levels before and after HD (ΔHb) with patient outcomes. The present study aimed to determine ΔHb and post-HD Hb levels with nationwide data and to examine their associations with all-cause mortality in patients undergoing HD.


Study Design: Retrospective cohort study
Setting and Participants: This study is based on data from 2008 and 2009 recorded in the Japanese Renal Data Registry.
Exposures: The ΔHb and the absolute post-HD Hb value.
Outcomes: 1-year mortality
Analytical Approach: The ΔHb and post-HD Hb level as categorical variables using Cox regression for 1-year mortality, adjusting for potential confounders.


Eligible patients were 38,636 patients. The median ΔHb was 1.0 g/dl (first quartile, 0.4 g/dl; third quartile, 1.5 g/dl), and the median post-HD Hb level was 11.3 g/dl 1.0 g/dl (first quartile, 10.3 g/dl; third quartile, 12.4 g/dl). The median pre-HD Hb level was 10.4 g/dl (first quartile, 9.6 g/dl; third quartile, 11.1 g/dl). The risk of mortality was lower with a ΔHb of 0 to 1.0 g/dl (adjusted hazard ratio [aHR], 0.82; 95% confidence interval [CI], 0.74–0.92) or > 1.0 g/dl (aHR, 0.62; 95% CI, 0.55–0.70) than with a ΔHb < 0 g/dl. The risk for mortality was also lower with a post-HD Hb of 10 to 11 g/dl (aHR, 0.79; 95% CI, 0.71–0.89), 11 to 12 g/dl (aHR, 0.72; 95% CI, 0.64–0.80), or > 12 g/dl (aHR, 0.71; 95% CI, 0.64–0.80) than with a post-HD Hb < 10 g/dl.


Both a low ΔHb and a low post-HD Hb level were associated with a higher risk of 1-year mortality.