Incident anaemia in older adults with heart failure: rate, aetiology, and association with outcomes

AIMS

Limited data exist on the epidemiology, evaluation, and prognosis of otherwise unexplained anaemia of the elderly in heart failure (HF). Thus, we aimed to determine the incidence of anaemia, to characterize diagnostic testing patterns for potentially reversible causes of anaemia, and to evaluate the independent association between incident anaemia and long-term morbidity and mortality.

METHODS AND RESULTS

Within the Cardiovascular Research Network (CVRN), we identified adults age ≥65 years with diagnosed HF between 2005 and 2012 and no anaemia at entry. Incident anaemia was defined using World Health Organization (WHO) haemoglobin thresholds (<13.0 g/dL in men; <12.0 g/dL in women). All-cause death and hospitalizations for HF and any cause were identified from electronic health records. Among 38 826 older HF patients, 22 163 (57.1%) developed incident anaemia over a median (interquartile range) follow-up of 2.9 (1.2-5.6) years. The crude rate [95% confidence interval (CI)] per 100 person-years of incident anaemia was 26.4 (95% CI 26.0-26.7) and was higher for preserved ejection fraction (EF) [29.2 (95% CI 28.6-29.8)] compared with borderline EF [26.5 (95% CI 25.4-27.7)] or reduced EF [26.6 (95% CI 25.8-27.4)]. Iron indices, vitamin B12 level, and thyroid testing were performed in 20.9%, 14.9%, and 40.2% of patients, respectively. Reduced iron stores, vitamin B12 deficiency, and/or hypothyroidism were present in 29.7%, 3.2%, and 18.6% of tested patients, respectively. In multivariable analyses, incident anaemia was associated with excess mortality [hazard ratio (HR) 2.14, 95% CI 2.07-2.22] as well as hospitalization for HF (HR 1.80, 95% CI 1.72-1.88) and any cause (HR 1.77, 95% CI 1.72-1.83).

CONCLUSION

Among older adults with HF, incident anaemia is common and independently associated with substantially increased risks of morbidity and mortality. Additional research is necessary to clarify the value of routine evaluation and treatment of potentially reversible causes of anaemia.

Lessons From the Testosterone Trials

The Testosterone Trials (TTrials) were a coordinated set of seven placebo-controlled, double-blind trials in 788 men with a mean age of 72 years to determine the efficacy of increasing the testosterone levels of older men with low testosterone. Testosterone treatment increased the median testosterone level from unequivocally low at baseline to midnormal for young men after 3 months and maintained that level until month 12. In the Sexual Function Trial, testosterone increased sexual activity, sexual desire, and erectile function. In the Physical Function Trial, testosterone did not increase the distance walked in 6 minutes in men whose walk speed was slow; however, in all TTrial participants, testosterone did increase the distance walked. In the Vitality Trial, testosterone did not increase energy but slightly improved mood and depressive symptoms. In the Cognitive Function Trial, testosterone did not improve cognitive function. In the Anemia Trial, testosterone increased hemoglobin in both men who had anemia of a known cause and in men with unexplained anemia. In the Bone Trial, testosterone increased volumetric bone mineral density and the estimated strength of the spine and hip. In the Cardiovascular Trial, testosterone increased the coronary artery noncalcified plaque volume as assessed using computed tomographic angiography. Although testosterone was not associated with more cardiovascular or prostate adverse events than placebo, a trial of a much larger number of men for a much longer period would be necessary to determine whether testosterone increases cardiovascular or prostate risk.

Functional Cardiac Recovery and Hematologic Response to Chemotherapy in Patients With Light-Chain Amyloidosis (from the Stanford University Amyloidosis Registry)

Cardiac involvement is common in patients with light-chain (AL) amyloidosis and portends a poor prognosis, although little is known about the changes in cardiac mechanics after chemotherapy. We sought to explore the relation between amyloidosis staging and baseline cardiac mechanics and to investigate short-term changes in cardiac mechanics after chemotherapy. We identified 41 consecutive patients from the Stanford Amyloid Center who had echocardiograms and free light-chain values before and after chemotherapy, along with 40 age- and gender-matched controls. Echocardiographic assessment included left ventricular global longitudinal strain, E/e' ratio, and left atrial (LA) stiffness. Hematologic response to chemotherapy was defined as ≥50% reduction in the difference between the involved and the uninvolved free light chain (dFLC). The mean age was 66.9 ± 8.4 years and 66% were men. Before chemotherapy, global longitudinal strain, E/e' ratio, and LA stiffness were impaired in patients with amyloidosis compared with controls, and the severity of impairment worsened with advanced staging. After chemotherapy, hematologic response was observed in 30 (73%) patients. There was a significant association between the change in dFLC and cardiac function (E/e' ratio: r = -0.43, p = 0.01; LA stiffness: r = -0.35, p = 0.05). There was no significant improvement in cardiac mechanics in patients without a hematologic response to chemotherapy. In conclusion, amyloidosis stage correlated with noninvasive measurements of cardiac mechanics, and improvement in dFLC correlated with cardiac improvement on short-term follow-up echocardiography.

Outcomes after heart transplantation for amyloid cardiomyopathy in the modern era

We conducted a review of patients undergoing heart transplantation (HT) at our institution for amyloid cardiomyopathy (ACM) between 2008 and 2013. Complete follow-up was available for all patients. Nineteen patients with ACM underwent HT during the study period, accounting for 9.4% of all HT performed at our institution during this period. Amyloid subtype was light chain (AL) in 9 patients and transthyretin (ATTR) in 10 (2 wild-type, 7 familial, 1 unknown). Eight of nine patients with AL amyloidosis began chemotherapy prior to HT, six have resumed chemotherapy since HT, and five have undergone autologous stem cell transplantation. Most recent free light chain levels in AL patients decreased by a median of 85% from peak values. Only one patient developed recurrent graft amyloidosis, occurring at 3.5 years post-HT and asymptomatic. After a median follow-up of 380 days, 17 (89.5%) patients are alive. To our knowledge, this is the largest single-center series reported of ACM patients undergoing HT in the modern era. Our results suggest that acceptable outcomes following HT can be achieved in the short-to-intermediate term and that this is a feasible option for end-stage ACM with careful patient selection and aggressive control of amyloidogenic light chains in AL patients.

Multiplicative interaction between mean corpuscular volume and red cell distribution width in predicting mortality of elderly patients with and without anemia

Recent studies have shown that an elevated red cell distribution width (RDW) is an important predictor of adverse outcomes. However, the strength of this biomarker has not been tested in a large outpatient elderly population. Also since increased RDW can be due to a variety of etiologies, additional biomarkers are needed to refine the prognostic value of this variable. We assembled a cohort of 36,226 elderly (≥65yo) patients seen at an outpatient facility within the Einstein/Montefiore system from January 1st 1997 to May 1st 2008 who also had a complete blood count performed within 3 months of the initial visit. With a maximum follow-up of 10 years, we found that an elevated RDW (>16.6) was associated with increased risk of mortality in both non-anemic (HR = 3.66, p < 0.05) and anemic patients (HR = 1.87, p < 0.05). The effect of RDW on mortality is significantly increased in non-anemic patients with macrocytosis (HR = 5.22, p < 0.05) compared to those with normocytosis (HR = 3.86, p < 0.05) and microcytosis (HR = 2.46, p < 0.05). When comparing non-anemic patients with both an elevated RDW and macrocytosis to those with neither, we observed an elevated HR of 7.76 (higher than expected in an additive model). This multiplicative interaction was not observed in anemic patients (HR = 2.23). Lastly, we constructed Kaplan-Meier curves for each RDW/MCV subgroup and found worsened survival for those with macrocytosis and an elevated RDW in both anemia and non-anemic patients. Based on our results, the addition of MCV appears to improve the prognostic value of RDW as a predictor of overall survival in elderly patients.

Enhanced macrophagic attack on beta-thalassemia major erythroid precursors

BACKGROUND AND OBJECTIVES

In beta-thalassemia major (Cooley's anemia), ferrokinetic studies show that 60-80% of erythroid precursors die in the marrow or extramedullary sites. However, study of marrow aspirates does not reveal huge numbers of dead and dying erythroid precursors. We explored this apparent discrepancy with the hypothesis that enhanced phagocytosis of thalassemic erythroid precursors was a likely explanation. Prior studies had reported on an increase in thalassemic marrow macrophages and their enhanced state of activation. Therefore this study explored the characteristics of thalassemic erythroid precursors which might lead to enhanced susceptibility to phagocytosis. We have shown that enhanced erythroid apoptosis parallels the extent of ineffective erythropoeisis in thalassemic patients, and apoptotic cells are rapidly phagocytosed. Thus, increased apoptosis and perhaps other features of thalassemic erythroid precursors might be the cause of their enhanced phagocytic removal.

DESIGN AND METHODS

Erythroid precursors were isolated from normal and beta-thalassemia major marrow, and incubated with uniform cultures of murine macrophages. The extent of phagocytosis was measured and then specific inhibitors were added to identify some of the messages effete erythroid precursors use to signal their condition to macrophages.

RESULTS

Beta-thalassemia major erythroid precursors are phagocytosed twice as effectively as normal erythroid precursors.

INTERPRETATION AND CONCLUSIONS

Experiments using inhibitors of phagocytosis showed that enhanced apoptosis is certainly responsible for part of the increased phagocytosis of thalassemic erythroid precursors. Interestingly, normal erythroid precursors are also subject to phagocytosis by qualitatively similar mechanisms.

Oxidation of hemoglobin F is associated with the aging process of neonatal red blood cells

Previously, we reported that in cord blood there is a population of very dense, surface area-depleted red blood cells (RBC). We hypothesized that oxidative damage might account for the generation of this cell population because Hb F is known to be mildly unstable in vitro. Accordingly, we examined density-separated subpopulations of neonatal red cells searching for evidence of oxidant injury to Hb in vivo. Cord or adult RBC were separated into populations of varying density and an increased amount of membrane-associated globin was found in the densest fraction of cord RBC. Solubilized ghosts from each fraction were analyzed by thiol-disulfide exchange chromatography for the presence of oxidized Hb and spectrophotometrically for the presence of membrane-bound hemichrome. About four times more oxidized Hb was found in unseparated cord RBC than in adult RBC. This difference was most evident in the densest 10-15% RBC subfractions. Membrane-bound hemichrome levels in cord cells were twice those found in adult cells. We found that in cord membrane skeletons there was 2.5 to 9 times as much globin in the dense fraction as compared to the light fraction. Membrane skeletons from dense and light adult RBC differed little from one another. We postulate that membrane (and perhaps membrane skeleton)-associated oxidized Hb is a marker for more generalized oxidative damage, which may create the population of unusually dense cells found in cord blood and ultimately shorten their life span.

The role of membrane skeletal-associated alpha-globin in the pathophysiology of beta-thalassemia

The beta-thalassemic mouse provides a useful model for testing hypotheses about the pathophysiology in human beta-thalassemia. The clinical picture of these mice and their red blood cell deformability characteristics are quite similar to those observed in human beta-thalassemia intermedia. The creation of transgenic mice that express human beta-globin (beta s) has provided an opportunity to study the effect of increasing the non-alpha-globin chain production on the thalassemic phenotype. A small increase in beta-globin production produces transgenic mice that are healthier, have almost normal hemoglobin values, and whose red blood cell deformability is increased. We quantified and characterized the membrane skeletal-associated globin in normal, transgenic thal/sickle, and thalassemic mice and showed that only alpha-globin was associated with the membrane skeleton in the pathologic red blood cells, and that the degree of rigidity as measured in the rheoscope correlated directly and closely with the amount of membrane skeletal-associated globin in these abnormal red blood cells.

Trisomy 4: an entity within acute nonlymphocytic leukemia

Trisomy 4 is a newly recognized primary chromosome change in leukemia. Five cases of acute nonlymphocytic leukemia (ANLL) are described from the United States and France. As in cases from Belgium, the only chromosome abnormality detected in the leukemic cells was trisomy 4. This was associated preferentially with ANLL of the M4 type (by FAB classification): acute myelomonocytic leukemia.

Unexpected hearing loss in high-risk infants

Eleven high-risk infants who had normal auditory brainstem responses at the time of discharge from the neonatal intensive care unit were found on follow-up between 13 and 48 months later to have significant sensorineural hearing loss. All 11 infants were the products of high-risk pregnancies and deliveries. Birth weights ranged from 890 to 3,700 g, but seven had birth weights of more than 1,500 g. Gestational ages ranged from 28 to 42 weeks. The length of hospitalization ranged from 45 to 167 days. All of the infants had respiratory distress, requiring prolonged mechanical ventilation with resultant chronic lung disease. All of the infants had received pancuronium, morphine, ampicillin, and gentamicin, and ten had also received furosemide and chlorothiazide. Other frequent clinical complications included abnormal CNS findings during the neonatal intensive care unit stay (ten infants), acidosis (pH less than 7.25) on the initial blood gas test (eight infants), and persistent fetal circulation in all seven infants with birth weights greater than 1,500 g. Developmentally, eight of nine children tested between 12 and 36 months of age were normal in all respects other than the hearing loss and the related language impairment. We conclude that infants who have been very ill in the newborn period, including term infants, may remain at risk for development of significant sensorineural hearing loss even though they have passed an initial auditory brainstem responses screening test in the newborn period.

Identification of the hereditary pyropoikilocytosis carrier state

We evaluated the hematologic, rheologic, and biochemical features of erythrocytes obtained from 10 relatives of a 5-yr-old black female with hereditary pyropoikilocytosis (HPP) and severe hemolytic anemia. Erythrocyte morphology was normal in the father and five other relatives, but ghost mechanical fragility and drug-induced red cell endocytosis were increased, as was the percentage of spectrin dimers noted on 3.2% nondenaturing PAGE of spectrin extracts. Identical changes were also noted in the mother and her sister, whose erythrocytes were elliptocytic and exhibited morphological changes upon heating to 45 degrees-48 degrees C (normal 49 degrees). The two other family members were normal in every respect. SDS-PAGE analysis of membrane proteins demonstrated diminished amounts of spectrin in HPP erythrocytes, but was normal in other family members. A diffuse band (mol wt 575,000-665,000), composed entirely of spectrin, was apparent adjacent to the dimer region on nondenaturing PAGE of spectrin extracts from the propositus, mother, and aunt. In this family, HPP appears to have resulted from compound heterozygosity for two distinct genetic abnormalities (reflected by the differences between elliptocytic and nonelliptocytic carriers). Although the membrane abnormalities in carriers did not result in hemolytic anemia, they were of sufficient magnitude to allow the detection of the carrier state.

The myeloproliferative disorders. Correlation between clinical evolution and alterations of granulopoiesis

Patients with myeloproliferative disorders were prospectively studied by in vitro agar-gel marrow culture technics to evaluate factors involved in the evolution of abnormal granulopoiesis. Marrow granulocytic colony-forming capacity was determined in 78 patients with chronic myeloid leukemia, subacute myeloid leukemia, preleukemia, Di Guglielmo's syndrome, polycythemia vera or essential thrombocythemia. A wide range of marrow colony-forming capacity values was noted early in disease courses; however, in 26 of 33 patients decreased colony-forming capacity was associated with disease transformation into acute myeloid leukemia or other clinically aggressive stages. An increased proportion of abnormally light buoyant density (less than 1.062 g/cm3) colony-forming cells was present in the marrow and peripheral blood of 15 of 16 patients with chronic myeloid leukemia, subacute myeloid leukemia, preleukemia or essential thrombocythemia; in seven of eight patients with greater than 35 per cent abnormally light colony-forming cells their disease subsequently underwent transformation. Elevated levels of urinary colony-stimulating factor output were noted in 17 of 31 patients, and in 10 of 12 patients whose disease subsequently underwent acute transformation within 10 months of study. In six of seven patients who simultaneously had an increased urinary output of colony-stimulating factor and low colony-forming capacity in marrow, transformation occurred within 10 months. These findings indicate that progressive abnormalities of both marrow clonal growth patterns and levels of possible humoral regulatory substances develop during evolution of these diseases. In contrast, patients with idiopathic sideroblastic ineffective erythropoiesis had normal values for marrow colony-forming capacity, proportion of light density colony-forming cells and urinary colony-stimulating factor output, and in none has their disease transformed into acute myeloid leukemia. These in vitro studies appear useful for clinical staging, evaluating prognosis and categorizing patients with myeloproliferative disorders.