In the Journals

Anemia linked to adverse outcomes, including increased dialysis risk, for patients with kidney disease

Researchers from Denmark found the presence of anemia was associated with an increased risk for incident dialysis in patients with chronic kidney disease. In addition, for these patients and those already on dialysis, anemia increased risks for hospitalization, mortality and major adverse cardiovascular events.

“Prevalent anemia in CKD has been associated with cognitive impairment, sleep disturbances, CKD progression, cardiovascular disease and higher mortality in mostly older studies and in selected populations,” Gunnar Toft, PhD, of the department of clinical epidemiology at Aarhus University Hospital in Denmark, and colleagues wrote. “Treatment options for anemia include iron (oral and intravenous), erythropoietin stimulating agents and red blood cell transfusion to restore the cardiovascular safety of treating anemia to higher hemoglobin levels. This has resulted in a change of anemia management practices since 2011, with generally less intensive therapy and lower hemoglobin treatment targets. Following this change, high-quality longitudinal real-world data on the current impact of anemia on clinical outcomes are scare.”

To determine the clinical consequences of anemia, researchers used population-based medical databases, from which 3,594 patients on dialysis and 24,916 patients with severe CKD (defined as eGFR < 30 mL/min/1.73m2) were identified. Patients were then classified as non-anemic (12 g/dl or 13 g/dl Hgb in men and women, respectively; 14% of study population), anemia grade 1 (10 g/dl to 12 g/dl or 13 g/dl; 35% of study population), anemia grade 2 (8 g/dl to 10 g/dl; 44% of study population) or anemia grade 3 and higher (< 8 g/dl; 17% of study population).

For patients who were not on dialysis at the start of the study, researchers found the rates of incident dialysis increased with higher anemia grades compared with patients who did not have anemia (for grade 3 or higher, adjusted HR = 1.91). Adjusted HRs were also elevated with grade 3 or higher anemia for any acute hospitalization (HR = 1.74), all-cause mortality (HR = 1.82) and major adverse cardiovascular events (HR = 1.14) vs. no anemia.

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Anemia was associated with an increased risk for incident dialysis in patients with chronic kidney disease.
Source: Adobe Stock

Risks of acute hospitalization, all-cause mortality and major adverse cardiovascular events were similar for patients on dialysis with increasing anemia grade.

“The duration of severe CKD, the number of acute hospitalizations, the proportion of patients on dialysis, [and those] with low eGFR (< 15 mL/min/1.73m2) and a high comorbidity score all increased with increasing anemia grade,” the researchers wrote. “In the current setting of generally less intensive anemia therapy, the present large study emphasizes the need for awareness of the potential risk of adverse clinical events in patients with CKD and anemia, and for further exploration of the interaction between anemia and progressive disease in CKD.”– by Melissa J. Webb

Disclosures: Toft reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.

Researchers from Denmark found the presence of anemia was associated with an increased risk for incident dialysis in patients with chronic kidney disease. In addition, for these patients and those already on dialysis, anemia increased risks for hospitalization, mortality and major adverse cardiovascular events.

“Prevalent anemia in CKD has been associated with cognitive impairment, sleep disturbances, CKD progression, cardiovascular disease and higher mortality in mostly older studies and in selected populations,” Gunnar Toft, PhD, of the department of clinical epidemiology at Aarhus University Hospital in Denmark, and colleagues wrote. “Treatment options for anemia include iron (oral and intravenous), erythropoietin stimulating agents and red blood cell transfusion to restore the cardiovascular safety of treating anemia to higher hemoglobin levels. This has resulted in a change of anemia management practices since 2011, with generally less intensive therapy and lower hemoglobin treatment targets. Following this change, high-quality longitudinal real-world data on the current impact of anemia on clinical outcomes are scare.”

To determine the clinical consequences of anemia, researchers used population-based medical databases, from which 3,594 patients on dialysis and 24,916 patients with severe CKD (defined as eGFR < 30 mL/min/1.73m2) were identified. Patients were then classified as non-anemic (12 g/dl or 13 g/dl Hgb in men and women, respectively; 14% of study population), anemia grade 1 (10 g/dl to 12 g/dl or 13 g/dl; 35% of study population), anemia grade 2 (8 g/dl to 10 g/dl; 44% of study population) or anemia grade 3 and higher (< 8 g/dl; 17% of study population).

For patients who were not on dialysis at the start of the study, researchers found the rates of incident dialysis increased with higher anemia grades compared with patients who did not have anemia (for grade 3 or higher, adjusted HR = 1.91). Adjusted HRs were also elevated with grade 3 or higher anemia for any acute hospitalization (HR = 1.74), all-cause mortality (HR = 1.82) and major adverse cardiovascular events (HR = 1.14) vs. no anemia.

#
Anemia was associated with an increased risk for incident dialysis in patients with chronic kidney disease.
Source: Adobe Stock

Risks of acute hospitalization, all-cause mortality and major adverse cardiovascular events were similar for patients on dialysis with increasing anemia grade.

“The duration of severe CKD, the number of acute hospitalizations, the proportion of patients on dialysis, [and those] with low eGFR (< 15 mL/min/1.73m2) and a high comorbidity score all increased with increasing anemia grade,” the researchers wrote. “In the current setting of generally less intensive anemia therapy, the present large study emphasizes the need for awareness of the potential risk of adverse clinical events in patients with CKD and anemia, and for further exploration of the interaction between anemia and progressive disease in CKD.”– by Melissa J. Webb

Disclosures: Toft reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.