[High frequency of anemia in COPD patients admitted in a tertiary hospital]

Anemia in chronic obstructive pulmonary disease: A systematic review

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is a type of obstructive lung disease that is characterized by poor airflow and airway inflammation. It is estimated that the global prevalence of COPD is about 13.1%. Anemia is associated with increased morbidity and hospitalization duration. In this systematic review, we investigate the association between all types of anemia and COPD progression.

METHODS

We systematically searched electronic databases, including Scopus, Medline/PubMed, EMBASE, Web of Sciences (WOS), and Cochrane Library, using the following mesh-standardized keywords: (((anemia∗ OR anaemia∗) OR "chronic anemia disease" [Mesh] OR "CAD" OR "iron deficiency anemia" OR" IDA" OR) AND ("COPD" [Mesh] OR "chronic obstructive pulmonary disease")) until February 2022.

RESULTS

Overall of 11,158 studies were included. Ultimately, 59 studies were included in the analysis. The most apparent findings from the analysis were that exacerbation of COPD, increased hospitalization, and increased long-term mortality were associated with anemia. Further analysis showed that iron deficiency (ID) is a common finding in COPD and is accompanied by an increase in the systolic pulmonary artery pressure.

CONCLUSION

Despite the comfortable control of anemia, the absence of treatment can be life-threatening in patients with COPD. Our systematic results showed significant homogeneity between studies on the increased mortality rate in anemic COPD, increased hospitalization, and decreased quality of life.

The Paradigm Shift from Polycythemia to Anemia in COPD: The Critical Role of the Renin-Angiotensin System Inhibitors

INTRODUCTION

Although polycythemia has been considered a common adverse event in COPD, anemia is reported more often and has gained more importance than polycythemia over the last thirty years.

AREAS COVERED

Factors considered to be associated with the development of anemia in COPD have included: Aging and kidney dysfunction with erythropoietin deficiency and bone marrow suppression due to uremic toxins; heart failure (HF), which is often encountered in COPD and is accompanied by anemia in one third of the cases; Low-grade chronic inflammation, which can directly suppresses the bone marrow and diminish iron absorption and utilization via increased hepcidin levels; long-term oxygen therapy (LTOT), which ameliorates chronic hypoxia, and most important, RAS inhibitors, which are widely used for the co-morbidities associated with COPD (hypertension, HF, CKD, diabetes) and have previously been shown to lower hematocrit values or cause anemia in various clinical conditions.

EXPERT OPINION

Introduction of LTOT in COPD and especially the established use of RAS inhibitors form the basis for the shift from polycythemia to anemia in COPD. Interestingly, when the SGLT2 inhibitors are introduced for cardiorenal protection in COPD, one could anticipate correction of anemia or even reemergence of polycythemia, since this new class of drugs can augment erythropoietin secretion and increase hematocrit values.

Management of the COPD Patient with Comorbidities: An Experts Recommendation Document

Background

Chronic obstructive pulmonary disease (COPD) is associated with multiple comorbidities, which impact negatively on patients and are often underdiagnosed, thus lacking a proper management due to the absence of clear guidelines.

Purpose

To elaborate expert recommendations aimed to help healthcare professionals to provide the right care for treating COPD patients with comorbidities.

Methods

A modified RAND-UCLA appropriateness method consisting of nominal groups to draw up consensus recommendations (6 Spanish experts) and 2-Delphi rounds to validate them (23 Spanish experts) was performed.

Results

A panel of Spanish internal medicine experts reached consensus on 73 recommendations and 81 conclusions on the clinical consequences of the presence of comorbidities. In general, the experts reached consensus on the issues raised with regard to cardiovascular comorbidity and metabolic disorders. Consensus was reached on the use of selective serotonin reuptake inhibitors in cases of depression and the usefulness of referring patients with anxiety to respiratory rehabilitation programmes. The results also showed consensus on the usefulness of investigating the quality of sleep, the treatment of pain with opioids and the evaluation of osteoporosis by lateral chest radiography.

Conclusion

This study provides conclusions and recommendations that are intended to improve the management of the complexity of patients with COPD and important comorbidities, usually excluded from clinical trials.

Role of Anemia in Home Oxygen Therapy in Chronic Obstructive Pulmonary Disease Patients

Anemia is a known comorbidity found in chronic obstructive pulmonary disease (COPD) patients. Hypoxemia is common and basically due to ventilation/perfusion (V/Q) mismatch in COPD. Anemia, by decreasing arterial oxygen content, may be a contributing factor for decreased delivery of oxygen to tissues. The objective of this study is to determine if anemia is a factor in qualifying COPD patients for home oxygen therapy. The study was designed as a retrospective, cross-sectional, observational chart review. Patients who were referred for home oxygen therapy evaluation were selected from the computerized patient record system. Demographic data, oxygen saturation at rest and during exercise, pulmonary function test results, hemoglobin level, medications, reason for anemia, comorbid diseases, and smoking status were recorded. The χ tests, independent sample t tests, and logistic regression were used for statistical analysis. Only 356 of total 478 patient referrals had a diagnosis of COPD over a 2-year period. Although 39 of them were excluded, 317 patients were included in the study. The overall rate of anemia was 38% in all COPD patients. Anemia was found significantly more frequent in COPD patients on home oxygen therapy (46%) than those not on home oxygen therapy (18.5%) (P < 0.0001). Mean saturation of peripheral oxygen values were significantly lower in anemic COPD patients both at rest and during exercise (P < 0.0001). Also, in COPD patients, age, Global Initiative for Chronic Obstructive Lung Disease class, smoking status, hemoglobin level, hematocrit, percent of forced expiratory volume in first second, forced expiratory volume in first second/forced vital capacity, residual volume/total lung volume, percent of carbon monoxide diffusion capacity were significantly different between home oxygen therapy and those not on home oxygen therapy (P < 0.05). Multivariate logistic regression showed that anemia remained a strong predictor for long-term oxygen therapy use in COPD patients after adjusting for other significant parameters. Anemic COPD patients are more hypoxic especially during exercise than those who are not anemic. We conclude that anemia is a contributing factor in qualifying COPD patients for home oxygen therapy.

Pulmonary and hemostatic toxicity of multi-walled carbon nanotubes and zinc oxide nanoparticles after pulmonary exposure in Bmal1 knockout mice

BACKGROUND

Pulmonary exposure to nanoparticles (NPs) may affect, in addition to pulmonary toxicity, the cardiovascular system such as procoagulant effects, vascular dysfunction and progression of atherosclerosis. However, only few studies have investigated hemostatic effects after pulmonary exposure.

METHODS

We used Bmal1 (brain and muscle ARNT-like protein-1) knockout (Bmal1(-/-)) mice which have a disturbed circadian rhythm and procoagulant phenotype, to study the pulmonary and hemostatic toxicity of multi-walled carbon nanotubes (MWCNTs) and zinc oxide (ZnO) NPs after subacute pulmonary exposure. Bmal1(-/-) and wild-type (Bmal1(+/+)) mice were exposed via oropharyngeal aspiration, once a week, during 5 consecutive weeks, to a cumulative dose of 32 or 128 μg MWCNTs or 32 or 64 μg ZnO NPs.

RESULTS

MWCNTs caused a pronounced inflammatory response in the lung with increased cell counts in the broncho-alveolar lavage and increased secretion of interleukin-1β and cytokine-induced neutrophil chemo-attractant (KC), oxidative stress (increased ratio of oxidized versus reduced glutathione and decreased total glutathione) as well as anemic and procoagulant effects as evidenced by a decreased prothrombin time with increased fibrinogen concentrations and coagulation factor (F)VII. In contrast, the ZnO NPs seemed to suppress the inflammatory (decreased neutrophils in Bmal1(-/-) mice) and oxidative response (increased total glutathione in Bmal1(-/-) mice), but were also procoagulant with a significant increase of FVIII. The procoagulant effects, as well as the significant correlations between the pulmonary endpoints (inflammation and oxidative stress) and hemostasis parameters were more pronounced in Bmal1(-/-) mice than in Bmal1(+/+) mice.

CONCLUSIONS

The Bmal1(-/-) mouse is a sensitive animal model to study the procoagulant effects of engineered NPs. The MWCNTs and ZnO NPs showed different pulmonary toxicity but both NPs induced procoagulant effects, suggesting different mechanisms of affecting hemostasis. However, the correlation analysis suggests a causal association between the observed pulmonary and procoagulant effects.

Defining COPD-Related Comorbidities, 2004-2014

Chronic obstructive pulmonary disease (COPD) is a disease of aging in combination with genetic, environmental, and behavioral risk factors. Aging and many of these risk factors are shared with other diseases, and, as a result, it is not surprising that patients with COPD often have coexistent diseases. This review of COPD comorbidities uses a framework in which coexistent diseases are considered important comorbidities if they are more frequent, have more severe consequences, influence the progression and outcomes of COPD, or are clustered together into proposed phenotypes, supplemented by a framework in which certain comorbidities are expected to share specific pathogenic mechanisms. This review explores classic COPD comorbidities such as cardiovascular disease, cachexia and sleep apnea, but also looks at more recently described comorbidities, such as gastroesophageal reflux, osteoporosis and depression/anxiety.

Anemia and iron deficiency in COPD patients: prevalence and the effects of correction of the anemia with erythropoiesis stimulating agents and intravenous iron

BACKGROUND

Little is known about iron deficiency (ID) and anemia in Chronic Obstructive Pulmonary Disease (COPD). The purposes of this study were: (i) To study the prevalence and treatment of anemia and ID in patients hospitalized with an exacerbation of COPD. (ii) to study the hematological responses and degree of dyspnea before and after correction of anemia with subcutaneous Erythropoiesis Stimulating Agents (ESAs) and intravenous (IV) iron therapy, in ambulatory anemic patients with both COPD and chronic kidney disease.

METHODS

(i) We examined the hospital records of all patients with an acute exacerbation of COPD (AECOPD) to assess the investigation, prevalence, and treatment of anemia and ID. (ii) We treated 12 anemic COPD outpatients with the combination of ESAs and IV-iron, given once weekly for 5 weeks. One week later we measured the hematological response and the severity of dyspnea by Visual Analogue Scale (VAS).

RESULTS

(i) Anemia and iron deficiency in hospitalized COPD patients: Of 107 consecutive patients hospitalized with an AECOPD, 47 (43.9%) were found to be anemic on admission. Two (3.3%) of the 60 non-anemic patients and 18 (38.3%) of the 47 anemic patients had serum iron, percent transferrin saturation (%Tsat) and serum ferritin measured. All 18 (100%) anemic patients had ID, yet none had oral or IV iron subscribed before or during hospitalization, or at discharge. (ii) Intervention outpatient study: ID was found in 11 (91.7%) of the 12 anemic ambulatory patients. Hemoglobin (Hb), Hematocrit (Hct) and the VAS scale scores increased significantly with the ESAs and IV-iron treatment. There was a highly significant correlation between the ∆Hb and ∆VAS; rs = 0.71 p = 0.009 and between the ∆Hct and ∆VAS; rs = 0.8 p = 0.0014.

CONCLUSIONS

ID is common in COPD patients but is rarely looked for or treated. Yet correction of the ID in COPD patients with ESAs and IV iron can improve the anemia, the ID, and may improve the dyspnea.

Anaemia in chronic obstructive pulmonary disease. Does it really matter?

Chronic obstructive pulmonary disease (COPD) is one of the most prevalent chronic diseases, with an increasing rate in morbidity and mortality. In recent years, there has been a greater awareness about the clinical importance of systemic effects and other chronic conditions associated with COPD, as these significantly impact on the course of disease. The most studied extrapulmonary manifestations in COPD include the presence of concomitant cardiovascular disease, skeletal muscle wasting, osteoporosis and lung cancer. Anaemia is a recognised independent marker of mortality in several chronic diseases. Recent studies have shown that anaemia in patients with COPD may be more frequent than expected, with a prevalence ranging from 5% to 33%. Some evidence suggests that systemic inflammation may play an important pathogenic role, but anaemia in COPD is probably multifactorial and may be caused by others factors, such as concealed chronic renal failure, decreased androgenic levels, iron depletion, angiotensin-converting enzyme inhibitor treatment and exacerbations. Low levels of haemoglobin and haematocrit in COPD patients have been associated with poor clinical and functional outcomes as well as with mortality and increased healthcare costs. Despite the potential clinical benefit of successfully treating anaemia in these patients, evidence supporting the importance of its correction on the prognosis of COPD is uncertain.

Anemia in chronic obstructive pulmonary disease: a readmission prognosis factor

OBJECTIVE

The prevalence of comorbid anemia in patients with COPD ranges from 7.5% to 34%. The aim of this study is to determine if anemia is a risk factor for readmission in COPD patients.

METHODS

This study analyzed the hospital data of 289,077 adults with acute exacerbations of COPD admitted to the hospital at any public center in Spain, in 2006 and 2007. We calculated the prevalence of anemia and compared readmissions between COPD patients with and without anemia. Multiple regression analyses were carried out with the aim of determining the risk of readmission attributable to anemia, after the correction of possible confounding variables.

RESULTS

Of the patients with COPD, 9.8% (n = 26,899) had a diagnosis of anemia. Anemic patients were older, more likely to be female and had a greater comorbidity burden than non-anemic individuals. Multiple regression modeling revealed that multiple independent factors were associated with an increased risk of readmission in persons with COPD. Anemia was one of the greatest risks: anemic patients had a 25% higher risk of readmission than non-anemic patients (odds ratio [OR], 1.25; 95% confidence interval [CI] 1.21-1.29).

CONCLUSION

Utilizing an administrative database the authors found that anemia correlates independently with readmission in COPD patients.

LIMITATIONS

This is a retrospective cohort study and thus subject to multiple forms of bias. Although spirometric evidence of COPD was not available, our case identification methods have been previously validated and found to be accurate in recognizing COPD.

Anemia is a mortality predictor in hospitalized patients for COPD exacerbation

BACKGROUND

Anemia is a recognized prognostic factor in many chronic illnesses, but there is limited information about its impact on outcomes in patients hospitalized for acute COPD exacerbation (AECOPD).

AIM

To investigate whether anemia exerts an effect on mortality in patients admitted for AECOPD after one year of follow-up. Methods. From November 2007 to November 2009 we recruited 117 patients who required hospitalization due to an AECOPD. Clinical, functional and laboratory parameters on admission were prospectively assessed. Patients were followed up during one year. Mortality and days-to-death were collected.

RESULTS

Mean age 72 (SD ± 9); FEV₁ 37.4 (SD ± 12); mortality after 1 year was 22.2%. Mean survival: 339 days. Comparing patients who died to those who survived we found significant differences (p < 0,000) in hemoglobin (Hb) (12.4 vs 13.8 mg/dl) and hematocrit (Ht) (38 vs 41%). Anemia (Hb < 13 g.dl⁻¹) prevalence was 33%. Those who died had experienced 3.5 exacerbations in previous year vs 1.5 exacerbations in the case of the survivors (p = 0.000). Lung function and nutritional status were similar, except for percentage of muscle mass (%) (35 vs 39%; p = 0.015) and albumin (33 vs 37 mg/dl; p = 0.039). These variables were included in a Multivariate Cox Proportional Hazards Model; anemia and previous exacerbations resulted as independent factors for mortality. Mortality risk for patients with anemia was 5.9(CI: 1.9-19); for patients with > 1 exacerbation in the previous year was 5.9(CI: 1.3-26.5).

CONCLUSION

Anemia and previous exacerbations were independent predictors of mortality after one year in patients hospitalized for AECOPD.

Restless legs syndrome--theoretical roles of inflammatory and immune mechanisms

Theories for restless legs syndrome (RLS) pathogenesis include iron deficiency, dopamine dysregulation and peripheral neuropathy. Increased prevalence of small intestinal bacterial overgrowth (SIBO) in controlled studies in RLS and case reports of post-infectious RLS suggest potential roles for inflammation and immunological alterations. A literature search for all conditions associated with RLS was performed. These included secondary RLS disorders and factors that may exacerbate RLS. All of these conditions were reviewed with respect to potential pathogenesis including reports of iron deficiency, neuropathy, SIBO, inflammation and immune changes. A condition was defined as highly-associated if there was a prevalence study that utilized an appropriate control group. Small case reports were recorded but not included as definite RLS-associated conditions. Fifty four diseases, syndromes and conditions have been reported to cause and/or exacerbate RLS. Of these, 38 have been reported to have a higher prevalence than age-matched controls, 9 have adequate sized reports and have general acceptance as RLS-associated conditions and 7 have been reported in case report form. Overall, 42 of the 47 RLS-associated conditions (89%) have also been associated with inflammatory and/or immune changes. In addition, 43% have been associated with peripheral iron deficiency, 40% with peripheral neuropathy and 32% with SIBO. Most of the remaining conditions have yet to be studied for these factors. The fact that 95% of the 38 highly-associated RLS conditions are also associated with inflammatory/immune changes suggests the possibility that RLS may be mediated or affected through these mechanisms. Inflammation can be responsible for iron deficiency and hypothetically could cause central nervous system iron deficiency-induced RLS. Alternatively, an immune reaction to gastrointestinal bacteria or other antigens may hypothetically cause RLS by a direct immunological attack on the central or peripheral nervous system.