Prevalence and Causes of Anemia in Hospitalized Patients: Impact on Diseases Outcome

Hemoglobin levels and cognitive trajectory: unveiling prognostic insights in post-stroke geriatric cohort

PURPOSE

Evidence is scarce regarding the association between anemia and alterations in cognitive level among hospitalized older patients. We aimed to evaluate the associations between baseline hemoglobin (Hb) levels and changes in cognitive level in patients undergoing rehabilitation after stroke.

METHODS

A retrospective cohort study was conducted, encompassing consecutively hospitalized post-stroke patients. Data on serum Hb levels were extracted from medical records, specifically tests conducted within 24 hours of admission. Primary outcomes included discharge scores for cognitive function assessed by the cognitive domain of the Functional Independence Measure (FIM-cognition) and the corresponding change in FIM-cognition during hospitalization. Another outcome measure was the length of hospital stay. Multivariate linear regression analyses were employed to assess the association between Hb levels at admission and the designated outcomes, adjusting for potential confounding factors.

RESULTS

Data from 955 patients (mean age 73.2 years; 53.6% men) were included in the analysis. The median Hb level at admission was 13.3 [11.9, 14.5] g/dL. After fully adjusting for confounding factors, the baseline Hb level was significantly and positively associated with FIM-cognition at discharge (β = 0.045, p = 0.025) and its gain (β = 0.073, p = 0.025). Further, the baseline Hb level was independently and negatively associated with length of hospital stay (β = -0.013, p = 0.026).

CONCLUSION

Elevated baseline Hb levels are correlated with preserved cognitive level and shorter hospital stays in post-stroke patients. Evaluating anemia at the outset serves as a crucial prognostic indicator.

Exploring the effects of post operative hyperoxic intermittent stimuli on reticulocyte levels in cancer patients: a randomized controlled study

BACKGROUND

Anemia is common among hospitalized critically ill and surgical oncological patients. The rising incidence of cancer and aggressive treatments has increased the demand for blood products, further strained by a dwindling donor pool. The normobaric oxygen paradox (NOP) has emerged as a potential avenue to increase EPO levels. While some studies support its efficacy, research remains limited in clinical settings. This study aims to assess the effectiveness of a NOP protocol in stimulating erythropoiesis, as measured by changes in reticulocyte counts, in cancer patients undergoing abdominal surgeries.

METHODS

This is a post hoc analysis of a prospective, single-center, controlled, randomized study. A total of 49 patients undergoing abdominal surgery were analyzed at the Institut Jules Bordet. Adult patients admitted to the intensive care unit (ICU) for at least 24 h were enrolled, excluding those with severe renal insufficiency or who received transfusions during the study period. Participants were randomized into two groups: a normobaric oxygen paradox (OXY) group who received 60% oxygen for 2 h on days 1, 3, and 5 post-surgery and a control (CTR) group who received standard care. Data on baseline characteristics, surgical details, and laboratory parameters were collected. Statistical analysis included descriptive statistics, chi-square tests, t-tests, Mann-Whitney tests, and linear and logistic regression.

RESULTS

The final analysis included 33 patients (median age 62 [IQR 58-66], 28 (84.8%) males, with no withdrawals or deaths during the study period. No significant differences were observed in baseline surgical characteristics or perioperative outcomes between the two groups. In the OXY group (n = 16), there was a significant rise (p = 0.0237) in the percentage of reticulocyte levels in comparison to the CTR group (n = 17), with median values of 36.1% (IQR 20.3-57.8) versus - 5.3% (IQR - 19.2-57.8), respectively. The increases in hemoglobin and hematocrit levels did not significantly differ between the groups when compared to their baselines' values.

CONCLUSIONS

This study provides preliminary evidence supporting the potential of normobaric oxygen therapy in stimulating erythropoiesis in cancer patients undergoing abdominal surgeries. While the OXY group resulted in increased reticulocyte counts, further research with larger sample sizes and multi-center trials is warranted to confirm these findings.

TRIAL REGISTRATION

The study was retrospectively registered under NCT number 06321874 on The 10th of April 2024.

Patient Blood Management as an Emerging Concept in Quality: The Role of Nurses

BACKGROUND

Transfusion of blood components has long been considered lifesaving therapy. While blood transfusion may be clinically indicated as a treatment option for some patients, the benefits of transfusion in asymptomatic, hemodynamically stable patients are questionable.

PROBLEM

Blood component transfusion is routinely used as a default therapy when not clinically indicated, increasing the risk of poor patient outcomes, adverse events, pressures on blood supply and availability, and increased health care costs.

APPROACH

Nurses have the responsibility to advocate for patients and reduce/avoid unnecessary blood transfusion through the implementation of patient blood management (PBM). The PBM paradigm includes treatment of anemia, minimizing blood loss and bleeding, optimization of coagulation, and employing true patient-centered decision making.

CONCLUSIONS

PBM should become the standard of care with the goal of improving health care quality and patient outcomes while using the multidisciplinary team for its implementation. As advocates for their patients, nurses can play a major role in the development, implementation, and promotion of PBM.

Adverse Outcomes of Patients with Non-Ventilator-Associated Hospital-Acquired Pneumonia (nvHAP)-A Single Centre Cohort Study

Non-ventilator associated hospital-acquired pneumonia (nvHAP) is a common nosocomial infection, but little is known about the outcomes of patients with nvHAP and the risk factors for adverse outcomes. In this retrospective study conducted in a Swiss tertiary care centre, adverse outcomes like in-hospital mortality, intensive care unit (ICU) admission, and mechanical ventilation, both all-cause and nvHAP-associated, were investigated. Of 244 patients with nvHAP, 72 (30%) died, 35 (14%) deaths were attributed to nvHAP. While 36 (15%) patients acquired nvHAP on the ICU, another 173 patients were eligible for ICU-transferral, and 76 (43.9%) needed ICU-admission. Of all patients hospitalized on the ICU 58 (51.8%) needed intubation due to nvHAP. Multivariable logistic regression analysis identified lower body mass index (OR per unit increase: 0.90, 95%CI: 0.82-0.98) and lower haemoglobin on admission (OR per unit in g/l increase: 0.98, 95%CI: 0.97-1.00) as patient specific factors independently associated with nvHAP-associated mortality. Given the frequency of nvHAP adverse outcomes, hospitals should evaluate increasing nvHAP prevention efforts, especially for patients at high risk for nvHAP mortality. To what extent pneumonia prevention interventions do lower nvHAP mortality in these patients is still to be evaluated.

Low hemoglobin levels are associated with compromised muscle health: Insights from a post-stroke rehabilitation cohort

AIM

There is limited evidence concerning the association between anemia and alterations in muscle health among hospitalized older patients. We aimed to evaluate the associations between baseline hemoglobin (Hb) levels and changes in muscle function in patients undergoing rehabilitation after stroke.

METHODS

This retrospective cohort study included consecutive hospitalized post-stroke patients. Data on serum Hb level were extracted from medical records on tests performed within 24 h of admission. The main outcomes were discharge score for the skeletal muscle mass index (SMI) obtained through bioimpedance analysis and the corresponding change in SMI during hospitalization. Other outcomes were handgrip strength (HGS) at discharge and the alteration in HGS during hospitalization. Multivariate linear regression analyses were used to determine the association between Hb levels at admission and outcomes of interest, adjusted for potential confounders.

RESULTS

Data from 955 patients (mean age 73.2 years; 53.6% men) were included in the analysis. The median Hb level at admission was 13.3 [11.9, 14.5] g/dL. After fully adjusting for confounding factors, the baseline Hb level was significantly and positively associated with SMI at discharge (β = 0.046, P = 0.039) and with SMI gain (β = 0.010, P = 0.039). Further, the baseline Hb level was independently and positively associated with HGS at discharge (β = 0.058, P = 0.014) and with its change from baseline (β = 0.100, P = 0.014).

CONCLUSION

Diminished baseline Hb levels were demonstrated be correlated with compromised muscle health in patients after stroke. Evaluating anemia at the outset serves as a crucial prognostic indicator. Geriatr Gerontol Int 2024; 24: 305-311.

Prevalence and Associated Factors of Anemia Among Hospital Admitted Patients in Eastern Ethiopia

Background

Anemia is one of the most common comorbidities frequently seen in admitted patients. However, there is a scarcity of evidence regarding anemia among hospital admitted patients in Ethiopia, particularly in the Harari Region. Therefore, this study aimed to assess the prevalence and associated factors of anemia among hospital admitted patients in Eastern Ethiopia.

Methods

A hospital-based cross-sectional study was conducted from October 25 to December 30, 2022. Four milliliters of venous blood were collected and complete blood count was done using the DxH 800 (Beckman Coulter, Inc, Miami, FL) hematology analyzer. The data were entered in Epi-data version 4 and exported to SPSS version 26 for statistical analysis. Bivariable and multivariable logistic regression models were fitted. The level of significance was declared at a p-value of < 0.05.

Results

Of the 381 hospital admitted patients, 64.8% (95% CI = 60.01, 69.65) of the participants were anemic. Admitted patients who drank standard alcohol daily (AOR = 3.78, 95% CI = 1.71, 8.30), underweight (AOR = 9.39, 95% CI = 2.90, 30.46), and undernourished patients (AOR = 2.59, 95% CI = 1.15, 5.84), patients admitted with chronic kidney disease (AOR = 11.16, 95% CI = 4.06, 30.64), chronic liver disease (AOR = 3.20, 95% CI = 1.21, 8.47), deep vein thrombosis (AOR = 6.22, 95% CI = 1.98, 19.52), infectious disease (AOR = 9.71, 95% CI = 2.77, 34.02), and chronic non-communicable disease (AOR = 7.01, 95% CI = 1.90, 25.99) were all significantly associated with anemia.

Conclusion

Anemia was common among hospital admitted patients and should prompt the focus on admission diagnoses that are likely to play leading roles in etiology. This information indicates a need for routine screening of anemia for all admitted patients to improve their health.

Appropriateness of packed red blood cells transfusions in chronic anemic patients in the emergency department: the TRANSFUS-ED retrospective analysis

Patients suffering from chronic anemia can benefit from scheduled transfusions of packed red blood cells (PRBCs), while urgent transfusions have specific indications. These patients frequently seek medical attention in the emergency department (ED), where they can be inappropriately transfused, but research in this field is limited. This study aimed to assess the appropriateness of PRBCs transfusions in chronic anemic patients in the ED. A retrospective analysis was performed on patients who accessed the ED of the Azienda Ospedaliera di Padova (Padova, Italy) between 2016 and 2019 and received PRBCs transfusions. Patients aged ≥ 18 years old and with chronic anemia were included, while those with acute anemia or admitted to the hospital after the transfusion were excluded. Chronic anemia was defined as satisfying one of the following in the past medical history: diagnosis of chronic anemia; two or more previous blood samplings demonstrating anemia; periodic transfusions. As primary outcome, the appropriateness of transfusions was assessed according to the American Association of Blood Banks (AABB) 2016 criteria, using the recommended threshold of 7 g/dL for hemodynamically stable adults and 8 g/dL for patients with pre-existing cardiovascular disease. Out of 1153 transfusions, 344 transfusions were included in the study. According to our criteria, 139 (40.4%) patients were inappropriately transfused, resulting in a total estimated cost of 54,528.71 € in the study period. This study showed that transfusions in chronic anemic patients are recurrent events in the ED and are frequently inappropriate. A possible explanation could be the lack of a well-structured primary care network granting periodic transfusions in ambulatory centers. In the future, implementing and improving chronic anemic patients' access to transfusion services through dedicated pathways could reduce the burden on the ED and also decrease costs.

Etiology of Anemia and Risk Factors of Mortality among Hospitalized Patients: A Real-Life Retrospective Study in a Tertiary Center in Greece

Anemia is a prominent global health issue with a wide variety of causes and can be associated with decreased quality of life, increased hospitalization, and higher mortality, especially in older individuals. Therefore, studies further shedding light on the causes and the risk factors of this condition should be performed. The aim of the present study was to examine the causes of anemia in hospitalized patients in a tertiary hospital in Greece and identify risk factors related to higher mortality. In total, 846 adult patients with a diagnosis of anemia were admitted during the study period. The median age was 81 years, and 44.8% were male. The majority of patients had microcytic anemia, with the median mean corpuscular volume (MCV) being 76.3 fL and the median hemoglobin being 7.1 g/dL. Antiplatelets were used by 28.6% of patients, while 28.4% were using anticoagulants at the time of diagnosis. At least one unit of packed red blood cells (PRBCs) was transfused in 84.6% of patients, and a median of two PRBCs was used per patient. A gastroscopy was performed in 55%, and a colonoscopy was performed in 39.8% of patients in the present cohort. Anemia was considered to be multifactorial in almost half the cases, while the most commonly identified cause was iron deficiency anemia, more commonly with positive endoscopic findings. Mortality was relatively low, at 4.1%. Multivariate logistic regression analysis identified higher B12 levels and longer duration of hospital stay to be independently positively associated with mortality.

Causes of Moderate and Severe Anaemia in a High-HIV and TB-Prevalent Adult Population in the Eastern Cape Province, South Africa

BACKGROUND

Anaemia affects one in four adults in South Africa, with a higher prevalence in persons with HIV and tuberculosis. The aim of this study is to characterise the causes of anaemia in primary care and a district hospital setting.

METHODS

A cross-sectional study design investigated a purposive sample of adult males and non-pregnant females at two community health centres and a hospital casualty and outpatients. Fingerpick blood haemoglobin was measured with HemoCueHb201+. Those with moderate and severe anaemia underwent clinical examination and laboratory tests.

RESULTS

Of 1327 patients screened, median age was 48 years, and 63.5% were female. Of 471 (35.5%) with moderate and severe anaemia on HemoCue, 55.2% had HIV, 16.6% tuberculosis, 5.9% chronic kidney disease, 2.6% cancer, and 1.3% heart failure. Laboratory testing confirmed 227 (48.2%) with moderate and 111 (23.6%) with severe anaemia, of whom 72.3% had anaemia of inflammation, 26.5% iron-deficiency anaemia, 6.1% folate deficiency, and 2.5% vitamin B12 deficiency. Overall, 57.5% had two or more causes of anaemia. Multivariate modelling showed that patients with severe anaemia were three times more likely to have tuberculosis (OR = 3.1, 95% CI = 1.5-6.5; p-value = 0.002). Microcytosis was present in 40.5% with iron deficiency, macrocytosis in 22.2% with folate deficiency, and 33.3% with vitamin B12 deficiency. The sensitivities of the reticulocyte haemoglobin content and % hypochromic red blood cells in diagnosing iron deficiency were 34.7% and 29.7%, respectively.

CONCLUSIONS

HIV, iron deficiency, and tuberculosis were the most prevalent causes of moderate and severe anaemia. The majority had multiple causes. Iron, folate, and vitamin B12 deficiencies should be identified by biochemical testing rather than by red cell volume.

Prevalence and Associated Factors of Iron Deficiency and Iron Deficiency Anemia Among Under-5 Children: A Systematic Review and Meta-Analysis

Background. Iron deficiency anemia is a common health problem that affects children under the age of five. Children’s cognitive performance is impaired by iron deficiency, which impacts their psychomotor development. Therefore, the aim of this study was to determine the global prevalence and associated factors of iron deficiency and iron deficiency anemia among under-5 children. Methods. Relevant publications published till March 30, 2021 were identified in databases such as Medline/PubMed, Science Direct, Popline, EMBASE, African Journals Online, Scopus, and Google Scholar. The STATA version 11 software was utilized for the analysis. To determine the level of heterogeneity, I² test statistics were used. To detect publication bias, funnel plots analysis and the Egger weighted regression test were used. Results. The global pooled prevalence of iron deficiency anemia and iron deficiency was 16.42% (95% CI: 10.82, 22.01) and 17.95% (95% CI: 13.49, 22.41), respectively. Age less than 2 years (OR = 1.26; 95% CI: 1.14, 1.38) and living in a large family size (OR = 1.38; 95% CI: 1.18, 1.58) were associated with iron deficiency anemia. Children born from anemic mother, low birth weight, and do not drink iron fortified milk (OR = 1.20; 95% CI: 1.05, 1.36), (OR = 1.15; 95% CI: 1.01, 1.36) and (OR = 1.28; 95% CI: 1.10, 1.46), respectively were associated factors of iron deficiency in under-5 children. Conclusion. The prevalence of iron deficiency anemia and iron deficiency was significant across the globe, particularly in Asia and Africa. Therefore, regular screening and treatment of iron deficiency and iron deficiency anemia are required especially in high-risk children to reduce their complication.

PROSPERO registration number: CRD42021267060

Admission criteria for a cardiovascular short stay unit: a retrospective analysis on a pilot unit

Rapid intensive observation (RIO) units have been created to guarantee high standards of care in a sustainable health-care system. Within short stay units (SSUs), which are a subgroup of RIOs, only rapidly manageable patients should be admitted. Physicians are unable to predict the length of stay (LOS) as objective criteria to make such a prediction are missing. A retrospective observational study was carried out to identify the objective criteria for admission within a cardiovascular care-oriented SSU. Over a period of 317 days, 340 patients (age 69.4 ± 14.7 years) were admitted to a pilot SSU within our internal medicine department. The most frequent diagnoses were chest pain (45.9%), syncope (12.9%), and supraventricular arrhythmias (11.2%). The median LOS was 4 days (quartile 1:3; quartile 3:7). Predictors of LOS ≤ 96 h were age < 80, hemoglobin > 115 g/L, estimated glomerular filtration rate > 45 mL/min/1.73 m², Charlson Comorbidity Index < 3, Barthel Index > 40, diagnosis of chest pain, syncope, supraventricular arrhythmias, or acute heart failure. The HEART (history, ECG, age, risk factors, troponin) score was found to be excellent in risk stratification of patients admitted for chest pain. Blood tests and anamnestic variables can be used to predict the LOS and thus SSU admission. The HEART score may help in the classification of patients with chest pain admitted to an SSU.

The Interplay between Anticholinergic Burden and Anemia in Relation to 1-Year Mortality among Older Patients Discharged from Acute Care Hospitals

Anticholinergic burden (ACB) and anemia were found associated with an increased risk of death among older patients. Additionally, anticholinergic medications may contribute to the development of anemia. Therefore, we aimed at investigating the prognostic interplay of ACB and anemia among older patients discharged from hospital. Our series consisted of 783 patients enrolled in a multicenter observational study. The outcome of the study was 1 year mortality. ACB was assessed by an Anticholinergic Cognitive Burden score. Anemia was defined as hemoglobin < 13 g/dL in men and <12 g/dL in women. The association between study variables and mortality was investigated by Cox regression analysis. After adjusting for several potential confounders, ACB score = 2 or more was significantly associated with the outcome in anemic patients (HR = 1.93, 95%CI = 1.13–3.40), but not non anemic patients (HR = 1.51, 95%CI = 0.65–3.48). An additive prognostic interaction between ACB and anemia was observed (p = 0.02). Anemia may represent a relevant effect modifier in the association between ACB and mortality.

Acute Anemia and Myocardial Infarction

Various studies have established the prognosis of anemia in myocardial infarction (MI). Both chronic and acute anemia lead to poor outcomes in MI. Regardless, the association of anemia with MI and its management varies. In this study, the literature was analyzed to determine the association between acute anemia and MI based on the pathophysiology, outcomes, and management options. Acute anemia results in decreased blood supply and sudden hypoxia to the heart. Additionally, it exacerbates the preexisting compromised coronary blood supply in patients with MI. Thus, there is a disproportionate oxygen supply and demand ratio to the heart. It was found that anemia increases all-cause mortality in acute MI. However, it is unclear whether anemia is the direct contributor to mortality in these patients. For the management of MI, percutaneous coronary intervention (PCI) is commonly used. Increased incidence of hospital-acquired anemia (HAA) is reported in patients after PCI. However, the cause of HAA in these patients is not well established. Antiplatelet therapy in these patients is also considered to be the culprit for HAA. Nonetheless, no clear evidence is available. There is no consensus or criteria for the treatment of acute anemia in MI patients. Researchers have explored management options such as blood transfusion, erythropoietin-stimulating agent, and iron therapy. Further studies are warranted for a better understanding and management of MI in patients with anemia and vice versa.

Extremely Old Patients Hospitalized in Internal Medicine: What about Their Anemia?

In western countries, about half of the hospitalized patients are anemic. Generally, these patients are old, often with multiple diseases, and anemia worsens the prognosis, finally increasing the risk of death. We describe a monocentric observational study that evaluates 249 consecutive adult patients (160 women and 89 men) with anemia admitted in the internal medicine department over five months. They represent 71.5% of all patients admitted in the study period. Demographic, historical, and clinical data, laboratory tests, duration of hospitalization, readmission at 30 days, and death were recorded. Patients were stratified by age (75-84=old, >85 years=oldest-old), anemia severity, and etiology of anemia. Anemia was found in 67.5% of old and in 77.2% of oldest-old patients. In 37% of old and 32% of oldest-old patients, anemia was mild, in 43% old and 59% of oldest-old moderate and in 20% old and 9% of oldest-old severe in agreement with WHO criteria. Moderate anemia was significantly more common in the oldest-old (p=0.01). The causes of anemia were iron deficiency in 10.6% of patients, other deficiencies in 2.8%, chronic diseases in 38.2%, hematologic neoplasms in 6.1%, multifactorial in 24.1%, and undetermined in 19.9%. The oldest-old have a higher frequency of multifactorial anemia (p=0.04), while hematologic neoplasms were more common in old patients (p=0.03). Most patients with undetermined anemia had mild/moderate forms. An anti-anemic treatment, mainly blood transfusion, was adopted in 100% of oldest-old patients and in 60% of old (p= 0.04). Anemia (and/or its treatment) was reported in the discharge letter in 19% of old and in 28.2% of oldestold patients. From a general point of view, physicians seem to disregard anemia in the context of more important pathologic conditions. In oldest-old patients, multifactorial anemia seems to be considered only "one more cause of disability." When borderline anemia occurs, even if it can represent a relevant adverse condition in frailty, it is poorly considered.

Length of hospital stay among oldest-old patients in acute geriatric ward

PURPOSE

To examine risk factors for prolonged hospital length of stay (LOS) in the oldest-old inpatients aged ≥ 90.

METHODS

This retrospective cross-sectional study was performed in acute Geriatrics Department at Kaplan Medical Center. The target population was the oldest-old inpatients aged ≥ 90 hospitalized with acute illness. In total 1536 admissions of 987 patients admitted between January 2007 and December 2010 from the emergency room were included in the study. We retrieved from the electronic hospital records the following data: demographics, admission diagnosis, comorbidities, laboratory tests, drugs, functional and cognitive status, Charlson Comorbidity Index (CCI) score and age-adjusted CCI score.

RESULTS

The risk factors for a prolonged LOS were tube-feeding, consumption of ≥ 5 drugs, non-independent functional status, diagnosis of urinary tract infection (UTI), pneumonia and malignancy on admission, and comorbidities of congestive heart failure (CHF) and hypoalbuminemia. Multiple linear regression analysis found that UTI, hypoalbuminemia, elevated troponin, pneumonia, number of drugs, malignancy, CHF and number of comorbidities explain a higher risk for a longer LOS.

CONCLUSION

Hospital LOS in the oldest-old patients in acute geriatric ward was associated with admission diagnosis and comorbidities. Awareness of the risk factors for a longer LOS might contribute to reducing hospitalization stay and its related negative consequences. Accurate prediction of prolonged LOS in this age group of patients may be more challenging and require variables that were not included in our study. Future research is warranted.

Iron in the General Population and Specificities in Older Adults: Metabolism, Causes and Consequences of Decrease or Overload, and Biological Assessment

Iron is involved in many types of metabolism, including oxygen transport in hemoglobin. Iron deficiency (ID), ie a decrease in circulating iron, can have severe consequences. We provide an update on iron metabolism and ID, highlighting the particularities in older adults (OAs). There are three iron compartments in the human body: 1) the functional compartment, which consists of heme proteins including hemoglobin, myoglobin and respiratory enzymes; 2) iron reserves (IR), which consist mainly of liver stocks and are stored as ferritin; and 3) transferrin. There are two types of ID. Absolute ID is characterized by a decrease in IR. Its main pathophysiological mechanism is bleeding, which is often digestive and can be due to neoplasia, frequent in OAs. Biological assessment shows low serum ferritin and transferrin saturation (TS) levels. Furthermore, hypochromic microcytic anemia is frequent, and the serum-soluble transferrin receptor (sTfR) level is high. Functional ID, in which IR are high or normal, is due to inflammation, which is also frequent in OAs, particularly in its chronic form. Biological assessments show high serum ferritin, normal or low TS, and normal sTfR levels. Moreover, C-reactive protein is elevated, and there is moderate non-regenerative non-macrocytic anemia. The main characteristics of iron metabolism anomalies in the elderly are the high frequency of ID (20% of ID with anemia in adults ≥85 years) and the severity of its consequences, which include cognitive impairment in case of ID or iron overload and decrease of physical activity in case of ID. In conclusion, causes of ID are frequently intertwined in OAs as a result of the polymorbidity that characterizes them. ID can have dramatic consequences, especially in frail OAs. Thus, measuring the appropriate biological markers prevents errors in the positive diagnosis of ID type, clarifies etiology, and informs treatment-related decision-making.