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The discrete Fourier transform (DFT) is the most commonly used signal processing method in modern digital sensor design for signal study and analysis. It is often implemented in hardware, such as a field programmable gate array (FPGA), using the fast Fourier transform (FFT) algorithm. The frequency resolution (i.e., frequency bin size) is determined by the number of time samples used in the DFT, when the digital sensor's bandwidth is fixed. One can vary the sensitivity of a radio frequency receiver by changing the number of time samples used in the DFT. As the number of samples increases, the frequency bin width decreases, and the digital receiver sensitivity increases. In some applications, it is useful to compute an ensemble of FFT lengths; e.g., 2P-j for j=0, 1, 2, , J, where j is defined as the spectrum level with frequency resolution 2j·Δf. Here Δf is the frequency resolution at j=0. However, calculating all of these spectra one by one using the conventional FFT method would be prohibitively time-consuming, even on a modern FPGA. This is especially true for large values of P; e.g., P≥20. The goal of this communication is to introduce a new method that can produce multi-resolution spectrum lines corresponding to sample lengths 2P-j for all J+1 levels, concurrently, while one long 2P-length FFT is being calculated. That is, the lower resolution spectra are generated naturally as by-products during the computation of the 2P-length FFT, so there is no need to perform additional calculations in order to obtain them.
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Coronavirus disease 2019 (COVID-19) infection in patients with haematological neoplasms has been associated with increased mortality; however, many studies in this patient group were reported early in the pandemic. The authors evaluated outcomes of COVID-19 infection in patients with haematological conditions following widespread vaccination, newer viral variants and increasingly effective antiviral therapies. A 4% mortality rate was found and contemporary risk factors for hospitalisation including older age, nonvaccination or partial COVID-19 vaccination status and infection with non-Omicron strain were identified.
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COVID-19 , Neoplasias Hematológicas , Hematologia , Humanos , SARS-CoV-2 , Vacinas contra COVID-19 , Neoplasias Hematológicas/terapiaRESUMO
BACKGROUND: Histologic transformation (HT) is an important event with adverse prognosis in the natural history of indolent lymphomas. There are minimal data on HT in the Australian setting. AIMS: To characterise patients with biopsy-proven HT and their outcomes identified at a tertiary Australian Hospital. METHODS: All patients with biopsy-proven HT during a 15-year period (2002-2017) were included. Clinico-pathological data were systematically collected from review of patient records. Survival estimates were assessed using the Kaplan-Meier method and compared using the log-rank test. Associations between variables and clinical outcomes were evaluated using Cox's proportional hazards model. RESULTS: A cohort of 45 patients was identified with a median age of 66 years and the majority (59%) having high-risk disease (Revised-International Prognostic Index score ≥3). R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisolone) induction was used in 69%, with an overall response rate of 82% (complete response (CR), 75%). Sixty-one percent of these induction responders received consolidation, with autologous stem cell transplant (ASCT) performed in only 17% and rituximab maintenance given to 31%. With a median follow up of 47 months (range: 4-136), the 5-year overall survival (OS) was 69% (95% CI: 52%, 81%). Chemotherapy-naivety at HT was associated with a superior rate of CR (84% vs 54%, P = 0.057) and 5-year OS (82% vs 46%, P = 0.012). Rituximab maintenance was associated with a durable progression-free survival in induction responders. CONCLUSIONS: Excellent OS was observed in this modern cohort of patients treated with rituximab-containing induction and low rate of consolidation by ASCT, particularly in those who were chemotherapy-naïve at HT.
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Transplante de Células-Tronco Hematopoéticas , Linfoma não Hodgkin , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Austrália/epidemiologia , Ciclofosfamida , Intervalo Livre de Doença , Doxorrubicina , Humanos , Recidiva Local de Neoplasia , Prednisona , Rituximab , Transplante Autólogo , VincristinaRESUMO
Recent studies have demonstrated that the immunomodulatory drugs (IMiDs) lead to the degradation of the transcription factors Ikaros and Aiolos. However, why their loss subsequently leads to multiple myeloma (MM) cell death remains unclear. Using CRISPR-Cas9 genome editing, we have deleted IKZF1/Ikaros and IKZF3/Aiolos in human MM cell lines to gain further insight into their downstream gene regulatory networks. Inactivation of either factor alone recapitulates the cell intrinsic action of the IMiDs, resulting in cell cycle arrest and induction of apoptosis. Furthermore, evaluation of the transcriptional changes resulting from their loss demonstrates striking overlap with lenalidomide treatment. This was not dependent on reduction of the IRF4-MYC "axis," as neither protein was consistently downregulated, despite cell death occurring, and overexpression of either factor failed to rescue for Ikaros loss. Importantly, Ikaros and Aiolos repress the expression of interferon-stimulated genes (ISGs), including CD38, and their loss led to the activation of an interferon-like response, contributing to MM cell death. Ikaros/Aiolos repressed CD38 expression through interaction with the nucleosome remodeling and deacetylase complex in MM. IMiD-induced loss of Ikaros or treatment with interferon resulted in an upregulation of CD38 surface expression on MM cells, priming for daratumumab-induced NK cell-mediated antibody-dependent cellular cytotoxicity. These results give further insight into the mechanism of action of the IMiDs and provide mechanistic rationale for combination with anti-CD38 monoclonal antibodies.
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Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacologia , Sistemas CRISPR-Cas , Fator de Transcrição Ikaros/genética , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , HumanosRESUMO
Antibody-secreting cells (ASCs) are critical for a functional and effective adaptive immune system. In a number of illnesses, however, these same cells contribute to the underlying disease state leading to significant morbidity and mortality. While therapeutic targeting of antibody-secreting cells has progressed significantly over the last two decades, many of these conditions remain major health problems. In this review, we will discuss current and potential therapeutic targeting of ASCs in the context of the known biology of these cells.
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Células Produtoras de Anticorpos/imunologia , Células Produtoras de Anticorpos/metabolismo , Plasmócitos/imunologia , Plasmócitos/metabolismo , Animais , Formação de Anticorpos , Células Produtoras de Anticorpos/citologia , Células Produtoras de Anticorpos/efeitos dos fármacos , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Sobrevivência Celular/genética , Sobrevivência Celular/imunologia , Suscetibilidade a Doenças , Regulação da Expressão Gênica , Humanos , Terapia de Alvo Molecular , Fenótipo , Plasmócitos/citologia , Plasmócitos/efeitos dos fármacos , Transcrição GênicaRESUMO
Iron deficiency and iron deficiency anaemia remain prevalent in Australia. The groups at highest risk are pre-menopausal women, socially disadvantaged people and those of Indigenous background. Diagnosing iron deficiency using a full blood examination and iron studies can be difficult and can be further complicated by concomitant inflammation. Results of iron studies should always be interpreted as an overall picture rather than focusing on individual parameters. In difficult clinical scenarios, soluble transferrin receptor assays can be useful. Management of iron deficiency involves identification and treatment of the cause of iron deficiency, as well as effective iron replacement. Clinicians should always take a detailed history and perform a comprehensive physical examination of a patient with iron deficiency. Patients should be monitored even if a likely cause of iron deficiency is identified. Patients who fail to respond to iron replacement or maintain iron status should be referred for further investigation, including endoscopy to exclude internal bleeding. Both enteral and parenteral iron are effective at replacing iron. For most adult patients, we recommend trialling daily oral iron (30-100 mg of elemental iron) as the first-line therapy. Safety and efficacy of intravenous iron infusions have improved with the availability of a newer formulation, ferric carboxymaltose. Patients who fail to respond to oral iron replacement can be safely managed with intravenous iron. Blood transfusion for iron deficiency anaemia should be reserved for life-threatening situations and should always be followed by appropriate iron replacement.
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Anemia Ferropriva/epidemiologia , Anemia Ferropriva/terapia , Compostos Férricos/administração & dosagem , Ferro/sangue , Maltose/análogos & derivados , Administração Oral , Anemia Ferropriva/etiologia , Austrália/epidemiologia , Transfusão de Sangue , Medula Óssea/patologia , Criança , Feminino , Compostos Férricos/efeitos adversos , Humanos , Infusões Intravenosas , Ferro/administração & dosagem , Deficiências de Ferro , Maltose/administração & dosagem , Maltose/efeitos adversos , GravidezAssuntos
COVID-19 , Mieloma Múltiplo , Pessoal de Saúde , Humanos , Mieloma Múltiplo/diagnóstico , SARS-CoV-2RESUMO
BACKGROUND: Iron-deficiency anaemia is highly prevalent among non-pregnant women of reproductive age (menstruating women) worldwide, although the prevalence is highest in lower-income settings. Iron-deficiency anaemia has been associated with a range of adverse health outcomes, which restitution of iron stores using iron supplementation has been considered likely to resolve. Although there have been many trials reporting effects of iron in non-pregnant women, these trials have never been synthesised in a systematic review. OBJECTIVES: To establish the evidence for effects of daily supplementation with iron on anaemia and iron status, as well as on physical, psychological and neurocognitive health, in menstruating women. SEARCH METHODS: In November 2015 we searched CENTRAL, Ovid MEDLINE, EMBASE, and nine other databases, as well as four digital thesis repositories. In addition, we searched the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) and reference lists of relevant reviews. SELECTION CRITERIA: We included randomised controlled trials (RCTs) and quasi-RCTs comparing daily oral iron supplementation with or without a cointervention (folic acid or vitamin C), for at least five days per week at any dose, to control or placebo using either individual- or cluster-randomisation. Inclusion criteria were menstruating women (or women aged 12 to 50 years) reporting on predefined primary (anaemia, haemoglobin concentration, iron deficiency, iron-deficiency anaemia, all-cause mortality, adverse effects, and cognitive function) or secondary (iron status measured by iron indices, physical exercise performance, psychological health, adherence, anthropometric measures, serum/plasma zinc levels, vitamin A status, and red cell folate) outcomes. DATA COLLECTION AND ANALYSIS: We used the standard methodological procedures of Cochrane. MAIN RESULTS: The search strategy identified 31,767 records; after screening, 90 full-text reports were assessed for eligibility. We included 67 trials (from 76 reports), recruiting 8506 women; the number of women included in analyses varied greatly between outcomes, with endpoint haemoglobin concentration being the outcome with the largest number of participants analysed (6861 women). Only 10 studies were considered at low overall risk of bias, with most studies presenting insufficient details about trial quality.Women receiving iron were significantly less likely to be anaemic at the end of intervention compared to women receiving control (risk ratio (RR) 0.39 (95% confidence interval (CI) 0.25 to 0.60, 10 studies, 3273 women, moderate quality evidence). Women receiving iron had a higher haemoglobin concentration at the end of intervention compared to women receiving control (mean difference (MD) 5.30, 95% CI 4.14 to 6.45, 51 studies, 6861 women, high quality evidence). Women receiving iron had a reduced risk of iron deficiency compared to women receiving control (RR 0.62, 95% CI 0.50 to 0.76, 7 studies, 1088 women, moderate quality evidence). Only one study (55 women) specifically reported iron-deficiency anaemia and no studies reported mortality. Seven trials recruiting 901 women reported on 'any side effect' and did not identify an overall increased prevalence of side effects from iron supplements (RR 2.14, 95% CI 0.94 to 4.86, low quality evidence). Five studies recruiting 521 women identified an increased prevalence of gastrointestinal side effects in women taking iron (RR 1.99, 95% CI 1.26 to 3.12, low quality evidence). Six studies recruiting 604 women identified an increased prevalence of loose stools/diarrhoea (RR 2.13, 95% CI 1.10, 4.11, high quality evidence); eight studies recruiting 1036 women identified an increased prevalence of hard stools/constipation (RR 2.07, 95% CI 1.35 to 3.17, high quality evidence). Seven studies recruiting 1190 women identified evidence of an increased prevalence of abdominal pain among women randomised to iron (RR 1.55, 95% CI 0.99 to 2.41, low quality evidence). Eight studies recruiting 1214 women did not find any evidence of an increased prevalence of nausea among women randomised to iron (RR 1.19, 95% CI 0.78 to 1.82). Evidence that iron supplementation improves cognitive performance in women is uncertain, as studies could not be meta-analysed and individual studies reported conflicting results. Iron supplementation improved maximal and submaximal exercise performance, and appears to reduce symptomatic fatigue. Although adherence could not be formally meta-analysed due to differences in reporting, there was no evident difference in adherence between women randomised to iron and control. AUTHORS' CONCLUSIONS: Daily iron supplementation effectively reduces the prevalence of anaemia and iron deficiency, raises haemoglobin and iron stores, improves exercise performance and reduces symptomatic fatigue. These benefits come at the expense of increased gastrointestinal symptomatic side effects.
Assuntos
Anemia Ferropriva/terapia , Suplementos Nutricionais , Deficiências de Ferro , Ferro/administração & dosagem , Menstruação/sangue , Adolescente , Adulto , Anemia Ferropriva/sangue , Suplementos Nutricionais/efeitos adversos , Feminino , Hemoglobina A , Humanos , Ferro/efeitos adversos , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como AssuntoAssuntos
Insuficiência Adrenal/induzido quimicamente , Artroplastia de Quadril/efeitos adversos , Hemorragia/induzido quimicamente , Complicações Pós-Operatórias , Embolia Pulmonar , Trombocitopenia/induzido quimicamente , Insuficiência Adrenal/diagnóstico por imagem , Idoso de 80 Anos ou mais , Feminino , Hemorragia/diagnóstico por imagem , Heparina de Baixo Peso Molecular , Humanos , Imageamento por Ressonância Magnética , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/terapia , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/etiologia , Embolia Pulmonar/terapia , Trombocitopenia/diagnóstico por imagemRESUMO
Animal and human observational studies suggest that iron deficiency impairs physical exercise performance, but findings from randomized trials on the effects of iron are equivocal. Iron deficiency and anemia are especially common in women of reproductive age (WRA). Clear evidence of benefit from iron supplementation would inform clinical and public health guidelines. Therefore, we performed a systematic review and meta-analysis to determine the effect of iron supplementation compared with control on exercise performance in WRA. We searched the Cochrane Central Register of Clinical Trials, MEDLINE, Scopus (comprising Embase and MEDLINE), WHO regional databases, and other sources in July 2013. Randomized controlled trials that measured exercise outcomes in WRA randomized to daily oral iron supplementation vs. control were eligible. Random-effects meta-analysis was used to calculate mean differences (MDs) and standardized MDs (SMDs). Risk of bias was assessed using the Cochrane risk-of-bias tool. Of 6757 titles screened, 24 eligible studies were identified, 22 of which contained extractable data. Only 3 studies were at overall low risk of bias. Iron supplementation improved both maximal exercise performance, demonstrated by an increase in maximal oxygen consumption (VO2 max) [for relative VO2 max, MD: 2.35 mL/(kg â min); 95% CI: 0.82, 3.88; P = 0.003, 18 studies; for absolute VO2 max, MD: 0.11 L/min; 95% CI: 0.03, 0.20; P = 0.01, 9 studies; for overall VO2 max, SMD: 0.37; 95% CI: 0.11, 0.62; P = 0.005, 20 studies], and submaximal exercise performance, demonstrated by a lower heart rate (MD: -4.05 beats per minute; 95% CI: -7.25, -0.85; P = 0.01, 6 studies) and proportion of VO2 max (MD: -2.68%; 95% CI: -4.94, -0.41; P = 0.02, 6 studies) required to achieve defined workloads. Daily iron supplementation significantly improves maximal and submaximal exercise performance in WRA, providing a rationale to prevent and treat iron deficiency in this group. This trial was registered with PROSPERO (http://www.crd.york.ac.uk/PROSPERO/prospero.asp) as CRD42013005166.
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Suplementos Nutricionais , Exercício Físico/fisiologia , Ferro da Dieta/administração & dosagem , Reprodução/efeitos dos fármacos , Anemia Ferropriva/tratamento farmacológico , Anemia Ferropriva/prevenção & controle , Feminino , Humanos , Estudos Observacionais como Assunto , Consumo de Oxigênio , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Background: Indolent T cell lymphoproliferation of the gastrointestinal tract is a novel entity recently added to the 2016 WHO classification of lymphoid neoplasms. Classically, these patients demonstrate an immunophenotype consistent with T cell proliferation and can be either CD4-positive or CD8-positive but with a low Ki67 index, highlighting the indolent nature of this disease compared to its more aggressive T cell lymphoma counterparts such as enteropathy-associated T cell lymphoma and monomorphic epitheliotropic intestinal T cell lymphoma. Methods: Here, we describe one rare case of such a neoplasm under our care, initially presenting with non-specific signs and symptoms and requiring extensive investigations to diagnose. Available cases in the literature reflect a wide variety of ages and ethnicities affected, and any part of the gastrointestinal sites can be affected, which makes diagnosis difficult and prolonged; however, progression beyond lymph nodes is rare, and prognosis is otherwise favourable, particularly if CD8-positive. The optimal management of these patients remains yet to be defined, given the paucity of available cases currently. The current evidence suggests the utility of steroids, cyclosporine, radiotherapy, and a potential role for JAK inhibitors. Conclusions: Our case showed an excellent response to the initial course of steroids, with a subsequent successful transition to cyclosporine, keeping symptoms at bay with ongoing stable disease.
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BACKGROUND: Bilateral adrenal hemorrhage is a rare but often a fatal cause of primary adrenal insufficiency that can result in adrenal crisis if not identified and managed appropriately. CASE PRESENTATION: We present a case of a 27-year-old Caucasian female who was admitted to the hospital 17 days postpartum with pleuritic chest and flank pain, shortness of breath and nausea. Computed tomography imaging confirmed multiple thromboemboli including pulmonary emboli and noted bilateral bulky adrenal glands. She was managed for infection and pulmonary emboli; however, she complained of persistent headaches, nausea, and vomiting despite appropriate management. Radiology re-review found the computed tomography imaging was consistent with bilateral adrenal hemorrhage in hindsight. Subsequent endocrine evaluation with hypothalamic-pituitary-adrenal axis interrogation and adrenocorticotropic hormone (Synacthen) stimulation testing confirmed resultant primary adrenal insufficiency. She required urgent intravenous hydrocortisone and was subsequently discharged on oral adrenal replacement therapy and anticoagulation. CONCLUSIONS: Delay in identification and treatment of adrenal insufficiency can lead to catastrophic outcomes. This case highlights the challenge of diagnosing bilateral adrenal hemorrhage and resultant adrenal insufficiency as patients may not present with the classic risk factors, signs, symptoms, and electrolyte derangements.
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Hemorragia , Hidrocortisona , Humanos , Feminino , Adulto , Hemorragia/etiologia , Hidrocortisona/uso terapêutico , Hidrocortisona/administração & dosagem , Período Pós-Parto , Doenças das Glândulas Suprarrenais/complicações , Doenças das Glândulas Suprarrenais/diagnóstico , Doenças das Glândulas Suprarrenais/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/tratamento farmacológico , Insuficiência Adrenal/tratamento farmacológico , Insuficiência Adrenal/complicações , Anticoagulantes/uso terapêuticoRESUMO
Early induction response assessment with day-21 bone marrow (D21-BM) is commonly performed in patients with FLT3-mutated acute myeloid leukaemia (AML), where detection of residual leukaemia (RL; blasts ≥5%) typically results in the administration of a second induction course. However, whether D21-BM results predict for RL at the end of first induction has not been systematically assessed. This study evaluates the predictive role of D21-BM morphology in detecting RL following first induction. Between August 2018 and March 2022, all patients with FLT3-AML receiving 7+3 plus midostaurin, with D21-BM performed, were identified. Correlation between D21-BM morphology vs D21-BM ancillary flow/molecular results, as well as vs D28-BM end of first induction response, were retrospectively reviewed. Subsequently, D21-BMs were subjected to anonymised morphological re-assessments by independent haematopathologists (total in triplicate per patient). Of nine patients included in this study, three (33%) were designated to have RL at D21-BM, all of whom entered complete remission at D28-BM. Furthermore, only low-level measurable residual disease was detected in all three cases by flow or molecular methods at D21-BM, hence none proceeded to a second induction. Independent re-evaluations of these cases failed to correctly reassign D21-BM responses, yielding a final false positive rate of 33%. In summary, based on morphology alone, D21-BM assessment following 7+3 intensive induction plus midostaurin for FLT3-AML incorrectly designates RL in some patients; thus correlating with associated flow and molecular results is essential before concluding RL following first induction. Where remission status is unclear, repeat D28-BMs should be performed.
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Medula Óssea , Leucemia Mieloide Aguda , Neoplasia Residual , Estaurosporina , Tirosina Quinase 3 Semelhante a fms , Humanos , Estaurosporina/análogos & derivados , Estaurosporina/uso terapêutico , Tirosina Quinase 3 Semelhante a fms/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Estudos Retrospectivos , Medula Óssea/patologia , Idoso , Mutação , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Indução de RemissãoRESUMO
Central nervous system (CNS) multiple myeloma (MM) is exceedingly rare and portends a dismal prognosis. While immunomodulators have contributed to the improvement in survival in MM, they appear to have limited activity against CNS MM and, paradoxically, may contribute to the evolution of resistant MM clones capable of surviving within the CNS. We undertook a retrospective analysis to characterize the features of CNS MM and outcome in 17 patients from four institutions identified between 2000 and 2011. The median age was 58 years. Patients had received a median of three prior therapies and all had been exposed to at least one of the so-called novel anti-MM agents before the diagnosis of CNS MM. The median time to CNS disease from initial diagnosis was 36 months. Cerebrospinal fluid (CSF) light chain measurements produced discrepant results to serum light chain measurements in some patients. Treatments included systemic pharmacotherapy, intrathecal (IT) chemotherapy and/or radiotherapy (RT). The median overall survival (OS) from diagnosis of CNS MM was only 4 months. OS was significantly better in patients who received IT chemotherapy (20 months vs. 2 months, respectively; P < 0.02). We conclude that the systematic evaluation of IT therapy and diagnostic utility of CSF light chain measurements in CNS MM are warranted.
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Antineoplásicos/administração & dosagem , Biomarcadores Tumorais/líquido cefalorraquidiano , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Cadeias lambda de Imunoglobulina/líquido cefalorraquidiano , Mieloma Múltiplo/tratamento farmacológico , Adulto , Idoso , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/sangue , Neoplasias do Sistema Nervoso Central/diagnóstico , Feminino , Humanos , Cadeias lambda de Imunoglobulina/sangue , Injeções Espinhais , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/radioterapia , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida , Fatores de Tempo , Resultado do TratamentoAssuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Adulto , Idoso , Bortezomib/administração & dosagem , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/patologia , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND: Anemia is an important public health and clinical problem. Observational studies have linked iron deficiency and anemia in children with many poor outcomes, including impaired cognitive development; however, iron supplementation, a widely used preventive and therapeutic strategy, is associated with adverse effects. Primary-school-aged children are at a critical stage in intellectual development, and optimization of their cognitive performance could have long-lasting individual and population benefits. In this study, we summarize the evidence for the benefits and safety of daily iron supplementation in primary-school-aged children. METHODS: We searched electronic databases (including MEDLINE and Embase) and other sources (July 2013) for randomized and quasi-randomized controlled trials involving daily iron supplementation in children aged 5-12 years. We combined the data using random effects meta-analysis. RESULTS: We identified 16 501 studies; of these, we evaluated 76 full-text papers and included 32 studies including 7089 children. Of the included studies, 31 were conducted in low- or middle-income settings. Iron supplementation improved global cognitive scores (standardized mean difference 0.50, 95% confidence interval [CI] 0.11 to 0.90, p = 0.01), intelligence quotient among anemic children (mean difference 4.55, 95% CI 0.16 to 8.94, p = 0.04) and measures of attention and concentration. Iron supplementation also improved age-adjusted height among all children and age-adjusted weight among anemic children. Iron supplementation reduced the risk of anemia by 50% and the risk of iron deficiency by 79%. Adherence in the trial settings was generally high. Safety data were limited. INTERPRETATION: Our analysis suggests that iron supplementation safely improves hematologic and nonhematologic outcomes among primary-school-aged children in low- or middle-income settings and is well-tolerated.