Factors Related to the Presence of Anemia in Patients with Chronic Kidney Disease in Hemodialysis

Research Article

Ann Hematol Oncol. 2021; 8(1): 1326.

Factors Related to the Presence of Anemia in Patients with Chronic Kidney Disease in Hemodialysis

Lizardi Gómez LF1, Reyes Sánchez I1, Guerrero Soto J1, Rivera Antolin JE1, Muñoz Menjivar C1, Venegas Vera AV1, Camarillo Rosas C2, Patiño Ortega R3, Arenas Osuna J4, Paniagua Sierra R5 and Hernández Rivera JCH5*

1Nephrology Service, Hospital de Especialidades, Centro Médico Nacional La Raza, Mexico

2Medical Director, Hospital General de Zona No. 27, Mexico

3Medical Director, Centro de Diagnóstico ángeles (CEDIASA) Guadalupe. Mexico City, Mexico

4Health Education and Research Department, Specialties Hospital, “La Raza” National Medical Center, Mexican Institute of Sovial Security (IMSS), México

5Medical Investigation Unit in Nephologic Diseases, Hospital de Especialidades, Centro Médico Nacional Siglo XXI, IMSS, Mexico

*Corresponding author: Juan Carlos H Hernández Rivera, Medical Investigation Unit in Nephologic Diseases, UMAE Hospital de Especialidades Bernardo Sepúlveda Gutiérrez, Centro Médico Nacional Siglo XXI. IMSS, Av. Cuauhtémoc 330, Col. Doctores, Mexico City, Mexico

Received: December 30, 2020; Accepted: February 03, 2021; Published: February 10, 2021


Introduction: The prevalence of anemia in Chronic Kidney Disease (CKD) is high. However, little is known about the factors related to anemia in patients with chronic Hemodialysis (HD) in Mexico.

Material and Methods: A cross-sectional study was conducted in adult patients with CKD undergoing HD in the northern area of Mexico City treated at the Mexican Institute of Social Security. Hemoglobin (Hb) and Hematocrit (Htc) levels, as well as clinical and biochemical factors associated with anemia, were evaluated.

Results: Data was collected from 747 patients, obtaining a mean hemoglobin of 9.7 g/dl (IQR 8.4-10.9 g/dl). The group was divided into two using Hb <10.0 g/dl and >10.0 g/dl as cutoff limits. Fifty six percent of the patients had hemoglobin =10.0 g/dl. Hb level <10.0 g/dl were associated with DM (OR 1.49, IC 95% 1.06-2.10, p=0.001), hyperphosphatemia (OR 1.69, IC 95% 1.21-2.28, p=0.001), high calcium-phosphate product (OR 1.43, IC 95% 1.01-2.03, p=0.040) and iron deficiency (OR 1.95, IC 95% 1.38-2.75, p=0.001). Glomerulopathies (OR 0.44, IC 95% 0.22-0.90, p=0.026), female gender (OR 0.55, IC 95% 0.40-0.074, p=0.001) and erythropoietin administration (OR 0.57, IC 95% 0.39-0.82, p=0.002) were associated with hemoglobin ≥10 g/dl.

Conclusion: The factors associated with Hb <10.0 g/dl were mineral-bone metabolism disorders and iron deficiency. The periodic evaluation of qualityof- care indicators of HD treatment, such anemia, are necessary to detect improvement opportunities.

Keywords: Anemia; Hemodialysis; Associated factors


Anemia is one of the earliest and most frequent manifestations of Chronic Kidney Disease (CKD).

CKD anemia is of multifactorial origin [1,2]. However, the immediate cause is the inadequate production of endogenous Erythropoietin (EPO) due to atrophy or injury to the renal peritubular cells responsible for its synthesis that, consequently, decreases the production of erythrocytes, promotes the apoptosis of erythroid progenitors and lessens the proliferation and differentiation of proerythroblasts and normoblasts [3]. Iron is another important factor related to the development of anemia; iron deficiency in CKD is frequent and reduces the synthesis of hemoglobin. Iron deficiency is a consequence of insufficient intestinal absorption associated to a chronic inflammatory state. On the other hand, gastrointestinal losses and during Hemodialysis (HD) can contribute significantly [4].

The factors involved in CKD anemia include hyperparathyroidism, a complication secondary to phosphorus retention that decreases the response to EPO [3-6]. The deficiency of folates or vitamin B12 also contributes to the development of anemia, specifically the macrocytic type, which has a frequency of 5% approximately, a proportion that may be higher in patients in HD, suggesting loss of vitamin B12 and folic acid during the HD [7].

The Angiotensin-Converting Enzyme Inhibitors (ACEI) and the Angiotensin Receptor Blockers (ARB) often employed in patients with CKD, participate in the production of anemia by inhibiting the erythropoietic effects of angiotensin II, in addition to reducing the EPO synthesis by increasing the renal blood flow [8-10].

In CKD, anemia is an independent risk factor to myocardial injury, it favours the development and progression of left ventricle hypertrophy and heart failure [11,12], additionally, increases the number of hospitalizations contributing to a declining quality of life and higher mortality [1,13]. Previous studies have shown that hemoglobin levels <8 g/dl and hematocrit <30% are associated with twice the risk of death compared to patients with hemoglobin between 10-11 g/dl and hematocrit among 33-36%. [14,15].

On account of its high frequency, its impact on the patients’ quality of life, and mainly because it is susceptible to intervention, the control of anemia is considered a quality-of-care indicator and has been included in international studies such as Dialysis Outcomes and Prescription Patterns Study (DOPPS) as an evaluation criteria, establishing the reference values that are associated with the best clinical outcome. Only developed countries participate in these studies, nevertheless its extension to developing countries is also highly important.

In Mexico’s case, the utmost proportion of patients in HD are treated by a single social security institution, IMSS. This institution outsources HD to private organizations through specific contracts in which certain management criteria are established, including anemia control. However, regarding the patient management both HD providers and IMSS participate, the latter with specialized consultations and input supply (EPO, supplemental iron, hematology consultation and drugs related). The coordination of this joint responsibility is complex, therefore the information related to the control of anemia is insufficient.

Based on the forementioned, the goal of this study was to identify the frequency in which the optimal levels of hemoglobin and hematocrit are achieved and the factors associated to the presence of values lower than those recommended in a population of patients receiving subrogate HD (extramural) by the Mexican Institute of Social Security (IMSS).

Materials and Methods

Design: A cross-sectional study was conducted with the total current patients treated in HD units outsourced by IMSS in the northern metropolitan area of Mexico City by December 31, 2019.

Patients: We included adult patients with CKD diagnosis from any cause, with no upper age limit, of either gender, treated in subrogated HD units. We excluded patients with less than three HD sessions per week and patients with chronic or acute infectious diseases documented at the beginning of the HD program. Pregnant patients and patients with bleeding history within 3 months previous to the study, were also excluded. Patients who deceased or had bleeding episodes during the study period were eliminated.

Data collection: The last serum hemoglobin value documented at the HD unit from every patient by December 31, 2019 was registered. Patients were classified into two groups according to the levels of hemoglobin establishing as cutoff values less than 10 g/dl (regarding the fulfilment of Hb goals in CKD patients) and patients without anemia for those with hemoglobin level >10 g/dl. Mean corpuscular volume, serum iron, transferrin saturation percentage and ferritin were recorded for both groups, as well as PTH concentration, number of transfusions, treatment with ACEI o ARB, iron and EPO doses registered on the IMSS medical record.

Statistics: Data is presented as mean and standard deviation (and interquartile range) or as frequency according with the variable type and their distribution. Comparisons between groups were established with chi square and Student’s t-test for variables with normal distribution, and Mann-Whitney U for those of free distribution. Variables with differences between groups were, subsequently, included in the logistic regression multivariate analysis to identify risk factors for the presence of hemoglobin and hematocrit values <10 g/ dL y 33%, respectively. The value of p-0.05 was considered significant. The statistical package SPSS version 25 was employed.


Study population characteristics. Nine hundred and five patients were eligible, of them, 110 patients fulfilled the exclusion criteria and 48 were eliminated, therefore 747 patients were considered for the analysis. The demographic and clinical data of the 747 patients are shown on (Table 1). The most frequent etiology for CKD was diabetes mellitus (24.9% of patients) and arterial hypertension (16.3%). Primary glomerulopathies were the cause in 5.5% of patients and less than 5% were found to originate secondarily from other entities, such as preeclampsia, polycystic kidney disease and vesicoureteral reflux, while forty-eight percent of patients did not have a determined etiology.