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The objective of this study is to develop and evaluate natural language processing (NLP) and machine learning models to predict infant feeding status from clinical notes in the Epic electronic health records system. The primary outcome was the classification of infant feeding status from clinical notes using Medical Subject Headings (MeSH) terms. Annotation of notes was completed using TeamTat to uniquely classify clinical notes according to infant feeding status. We trained 6 machine learning models to classify infant feeding status: logistic regression, random forest, XGBoost gradient descent, k-nearest neighbors, and support-vector classifier. Model comparison was evaluated based on overall accuracy, precision, recall, and F1 score. Our modeling corpus included an even number of clinical notes that was a balanced sample across each class. We manually reviewed 999 notes that represented 746 mother-infant dyads with a mean gestational age of 38.9 weeks and a mean maternal age of 26.6 years. The most frequent feeding status classification present for this study was exclusive breastfeeding [n = 183 (18.3%)], followed by exclusive formula bottle feeding [n = 146 (14.6%)], and exclusive feeding of expressed mother's milk [n = 102 (10.2%)], with mixed feeding being the least frequent [n = 23 (2.3%)]. Our final analysis evaluated the classification of clinical notes as breast, formula/bottle, and missing. The machine learning models were trained on these three classes after performing balancing and down sampling. The XGBoost model outperformed all others by achieving an accuracy of 90.1%, a macro-averaged precision of 90.3%, a macro-averaged recall of 90.1%, and a macro-averaged F1 score of 90.1%. Our results demonstrate that natural language processing can be applied to clinical notes stored in the electronic health records to classify infant feeding status. Early identification of breastfeeding status using NLP on unstructured electronic health records data can be used to inform precision public health interventions focused on improving lactation support for postpartum patients.
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Aprendizaje Automático , Procesamiento de Lenguaje Natural , Femenino , Humanos , Lactante , Programas Informáticos , Registros Electrónicos de Salud , MadresRESUMEN
INTRODUCTION: Wilson's disease (WD) is associated with a variety of movement disorders and progressive neurological dysfunction. The aim of this study was to correlate baseline brain magnetic resonance imaging (MRI) features with clinical phenotype and long-term outcomes in chronically treated WD patients. METHODS: Patients were retrospectively selected from an institutional database. Two experienced neuroradiologists reviewed baseline brain MRI. Functional assessment was performed using the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) scale, and disease severity was classified using the Global Assessment Scale for Wilson's Disease (GASWD). RESULTS: Of 27 patients selected, 14 were female (51.9%), with a mean (standard deviation [SD]) age at onset of 19.5 (7.1) years. Neurological symptoms developed in 22 patients (81.5%), with hyperkinetic symptoms being the most common (70.4%). Baseline brain MRI showed abnormal findings in 18 cases (66.7%), including T2 hyperintensities in 59.3% and atrophy in 29.6%. After a mean (SD) follow-up of 20.9 (11.0) years, WD patients had a mean score of 19.2 (10.2) on WHODAS 2.0 and 6.4 (5.7) on GASWD. The presence of hyperkinetic symptoms correlated with putaminal T2 hyperintensities (p = 0.003), putaminal T2 hypointensities (p = 0.009), and mesencephalic T2 hyperintensities (p = 0.009). Increased functional disability was associated with brain atrophy (p = 0.007), diffusion abnormalities (p = 0.013), and burden of T2 hyperintensities (p = 0.002). A stepwise regression model identified atrophy as a predictor of increased WHODAS 2.0 (p = 0.023) and GASWD (p = 0.007) scores. CONCLUSIONS: Atrophy and, to a lesser extent, deep T2 hyperintensity are associated with functional disability and disease severity in long-term follow-up of WD patients.
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Encéfalo , Degeneración Hepatolenticular , Imagen por Resonancia Magnética , Fenotipo , Humanos , Femenino , Degeneración Hepatolenticular/diagnóstico por imagen , Degeneración Hepatolenticular/fisiopatología , Degeneración Hepatolenticular/patología , Masculino , Adulto Joven , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Encéfalo/fisiopatología , Adulto , Estudios Retrospectivos , Adolescente , Neuroimagen/métodos , Índice de Severidad de la Enfermedad , Evaluación de la Discapacidad , Niño , Estudios de Seguimiento , Atrofia/patologíaRESUMEN
Epidemiological data demonstrate that bovine whole milk is often substituted for human milk during the first 12 months of life and may be associated with adverse infant outcomes. The objective of this study is to interrogate the human and bovine milk metabolome at 2 weeks of life to identify unique metabolites that may impact infant health outcomes. Human milk (n = 10) was collected at 2 weeks postpartum from normal-weight mothers (pre-pregnant BMI < 25 kg/m2) that vaginally delivered term infants and were exclusively breastfeeding their infant for at least 2 months. Similarly, bovine milk (n = 10) was collected 2 weeks postpartum from normal-weight primiparous Holstein dairy cows. Untargeted data were acquired on all milk samples using high-resolution liquid chromatography-high-resolution tandem mass spectrometry (HR LC-MS/MS). MS data pre-processing from feature calling to metabolite annotation was performed using MS-DIAL and MS-FLO. Our results revealed that more than 80% of the milk metabolome is shared between human and bovine milk samples during early lactation. Unbiased analysis of identified metabolites revealed that nearly 80% of milk metabolites may contribute to microbial metabolism and microbe-host interactions. Collectively, these results highlight untargeted metabolomics as a potential strategy to identify unique and shared metabolites in bovine and human milk that may relate to and impact infant health outcomes.
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Lactancia Materna , Espectrometría de Masas en Tándem , Animales , Femenino , Lactante , Embarazo , Humanos , Bovinos , Cromatografía Liquida , Lactancia , Leche Humana , MetabolómicaRESUMEN
Background and Objectives: The RFC1 spectrum has become considerably expanded as multisystemic features beyond the triad of cerebellar ataxia, neuropathy, and vestibular areflexia syndrome (CANVAS) have started to be unveiled, although many still require clinical replication. Here, we aimed to clinically characterize a cohort of RFC1-positive patients by addressing both classic and multisystemic features. In a second part of this study, we prospectively assessed small nerve fibers (SNF) and autonomic function in a subset of these RFC1-related patients. Methods: We retrospectively enrolled 67 RFC1-positive patients from multiple neurologic centers in Portugal. All patients underwent full neurologic and vestibular evaluation, as well as neuroimaging and neurophysiologic studies. For SNF and autonomic testing (n = 15), we performed skin biopsies, quantitative sensory testing, sudoscan, sympathetic skin response, heart rate deep breathing, and tilt test. Results: Multisystemic features beyond CANVAS were present in 82% of the patients, mainly chronic cough (66%) and dysautonomia (43%). Other features included motor neuron (MN) affection and motor neuropathy (18%), hyperkinetic movement disorders (16%), sleep apnea (6%), REM and non-REM sleep disorders (5%), and cranial neuropathy (5%). Ten patients reported an inverse association between cough and ataxia severity. A very severe epidermal denervation was found in skin biopsies of all patients. Autonomic dysfunction comprised cardiovascular (67%), cardiovagal (54%), and/or sudomotor (50%) systems. Discussion: The presence of MN involvement, motor neuropathy, small fiber neuropathy, or extrapyramidal signs should not preclude RFC1 testing in cases of sensory neuronopathy. Indeed, the RFC1 spectrum can overlap not only with multiple system atrophy but also with hereditary motor and sensory neuropathy, hereditary sensory and autonomic neuropathy, and feeding dystonia phenotypes. Some clinical-paraclinical dissociations can pose diagnostic challenges, namely large and small fiber neuropathy and sudomotor dysfunction which are usually subclinical.
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Mitochondrial diseases are the most common inherited inborn error of metabolism resulting in deficient ATP generation, due to failure in homeostasis and proper bioenergetics. The most frequent mitochondrial disease manifestation in children is Leigh syndrome (LS), encompassing clinical, neuroradiological, biochemical, and molecular features. It typically affects infants but occurs anytime in life. Considering recent updates, LS clinical presentation has been stretched, and is now named LS spectrum (LSS), including classical LS and Leigh-like presentations. Apart from clinical diagnosis challenges, the molecular characterization also progressed from Sanger techniques to NGS (next-generation sequencing), encompassing analysis of nuclear (nDNA) and mitochondrial DNA (mtDNA). This upgrade resumed steps and favored diagnosis. Hereby, our paper presents molecular and clinical data on a Portuguese cohort of 40 positive cases of LSS. A total of 28 patients presented mutation in mtDNA and 12 in nDNA, with novel mutations identified in a heterogeneous group of genes. The present results contribute to the better knowledge of the molecular basis of LS and expand the clinical spectrum associated with this syndrome.
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Enfermedad de Leigh , Niño , Lactante , Humanos , Enfermedad de Leigh/genética , Portugal , ADN Mitocondrial/genética , Mitocondrias , Evolución BiológicaRESUMEN
Brain manganese (Mn) accumulation is a key feature in patients with acquired hepatocerebral degeneration (AHD). The role of trace elements other than Mn in AHD needs to be clarified. In this study, using inductively coupled plasma mass spectrometry, we aimed to evaluate blood levels of trace elements in patients with AHD before and after liver transplantation (LT). Trace element levels in the AHD group were also compared with those of healthy controls (blood donors, n = 51). Fifty-one AHD patients were included in the study (mean age: 59.2 ± 10.6 years; men: 72.5%). AHD patients had higher levels of Mn, Li, B, Ni, As, Sr, Mo, Cd, Sb, Tl and Pb and a higher Cu/Se ratio, and lower levels of Se and Rb. Six patients (two women; mean age 55 ± 8.7 years) underwent LT, and there was an improvement in neurological symptoms, a significant increase in the Zn, Se and Sr levels, and a decrease in the Cu/Zn and Cu/Se ratios. In summary, several trace element imbalances were identified in AHD patients. Liver transplantation resulted in the improvement of neurological manifestations and the oxidant/inflammatory status. It is possible that observed changes in trace element levels may play a role in the pathophysiology and symptomatology of AHD.
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INTRODUCTION: The diagnostic approach for adulthood parkinsonism can be challenging when atypical features hamper its classification in one of the two main parkinsonian groups: Parkinson's disease or atypical parkinsonian syndromes (APS). Atypical features are usually associated with non-sporadic neurodegenerative causes. METHODS: Retrospective analysis of patients with a working clinical diagnosis of "atypical" APS and complex parkinsonism. "Atypical" APS were classified according to the diagnostic research criteria and the "4-step diagnostic approach" (Stamelou et al. 2013). When not indicated, the final aetiological diagnosis was prospectively assessed. Brain MRI of progressive supranuclear palsy (PSP) look-alikes was reviewed by a neuroradiologist. RESULTS: Among 18 patients enrolled, ten were assigned to the "atypical" APS and eight to the complex parkinsonism group. In the "atypical" APS group, nine patients had PSP and one had corticobasal degeneration. In the PSP group the median magnetic resonance parkinsonism index was 17.1. A final aetiological diagnosis was established for 11 patients, four from the complex parkinsonism (L-2-hidroxiglutaric aciduria and DiGeorge syndrome) and seven from the "atypical" APS (Perry syndrome, postencephalitic PSP, vascular PSP, and MTP-AT6 mitochondrial disease) group. CONCLUSIONS: In this study, the identification of atypical APS features, as proposed in the "4-step diagnostic approach", successfully guided the investigation of alternative diagnoses. Distinctive non-neurodegenerative etiologies causing "atypical" atypical and complex parkinsonism were uncovered, including acquired (post-encephalitis and vascular) and genetic (MTP-AT6 mitochondrial disease mimicking PSP, described for the first time) ones. In the future, accurate clinical identification and distinction between neurodegenerative and non-neurodegenerative parkinsonism etiologies will allow for refining clinical trials.
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Enfermedad de Parkinson , Trastornos Parkinsonianos , Parálisis Supranuclear Progresiva , Humanos , Adulto , Estudios Retrospectivos , Trastornos Parkinsonianos/diagnóstico por imagen , Trastornos Parkinsonianos/genética , Enfermedad de Parkinson/diagnóstico , Parálisis Supranuclear Progresiva/diagnóstico por imagen , Parálisis Supranuclear Progresiva/genética , Depresión , Diagnóstico DiferencialRESUMEN
OBJECTIVE: To assess the feasibility and potential benefits of personalized biomarker-based text messages in prolonging lactation among parents of critically ill infants. STUDY DESIGN: Thirty-six participants were randomized to receive either daily texts with Mother's Own Milk (MOM) sodium levels or standard care. Surveys at months 1 and 3 assessed whether infants were receiving exclusive MOM feeding, any MOM feeding, and whether the parent was still lactating. Kaplan-Meier and log-rank tests were used for time-to-event analysis within and between intervention and control groups. RESULTS: Participants were predominantly on Medicaid (72%), delivered infants <1500 g, and by c-section (56%). Kaplan-Meier probabilities at month 3 suggest prolonged MOM feeding (63% [0.95CI, 0.43-0.91] vs. 41% [0.95CI, 0.21-0.67]) and lactation (63% [0.95CI, 0.42-0.95] vs. 37% [0.95CI, 0.18-0.76]) in the enhanced group compared to the control group. CONCLUSION: Personalized biomarker-based text messages are feasible and may prolong lactation and MOM feeding among parents of critically ill infants.
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Enfermedad Crítica , Lactancia , Femenino , Lactante , Humanos , Recién Nacido , Proyectos Piloto , Fenómenos Fisiológicos Nutricionales del Lactante , Lactancia Materna , Leche Humana , Madres , Padres , Biomarcadores , Unidades de Cuidado Intensivo NeonatalRESUMEN
The COVID-19 pandemic underscored the importance of vaccination to support individual health across the life-course, with vaccination playing a central strategy role in mitigating transmission and disease. This required unprecedented mobilization and coordination across all sectors to meet people where they are, enable equitable access, and build vaccination confidence. A literature search was conducted with combinations of the keywords and variations of vaccination and faith-based organizations (FBOs). Search inclusion criteria were: (1) FBO programs that supported public health emergency efforts, including vaccination efforts as the primary outcome; and (2) articles written in English language. A total of 37 articles met inclusion criteria (n = 26 focused on general public health campaigns, n = 11 focused on vaccination efforts). The findings related to public health campaigns fell into four themes: FBO's ability to (1) tailor public health campaigns; (2) mitigate barriers; (3) establish trust; and (4) disseminate and sustain efforts. The findings related to vaccine uptake efforts fell into three themes: (1) pre-pandemic influenza and HPV vaccination efforts, (2) addressing vaccine disparities in minority communities, and (3) enabling COVID-19 vaccination. This review demonstrated that FBOs have a vital role in both public health campaigns and vaccination initiatives to support high vaccine uptake and confidence.
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BACKGROUND: Estimates by the World Health Organization indicate that over 800,000 global neonatal deaths each year are attributed to deviations from recommended best practices in infant feeding. Identifying factors promoting ideal breastfeeding practices may facilitate efforts to decrease neonatal and infant death rates and progress towards achieving the Sustainable Development Goals set for 2030. Though numerous studies have identified the benefits of breastfeeding in reducing the risk of childhood undernutrition, infection and illness, and mortality in low- and middle-income countries, no studies have explored predictors of breastfeeding practices in rural eastern Ethiopia, where undernutrition is widespread. The aim of this study is to examine predictors of infant feeding practices in Haramaya, Ethiopia, using a multi-level conceptual framework. METHODS: This study uses data collected from household questionnaires during the Campylobacter Genomics and Environmental Enteric Dysfunction (CAGED) project among 102 households in the Haramaya woreda, Eastern Hararghe Zone, Eastern Ethiopia, and investigates factors influencing breastfeeding practices: early initiation, prelacteal feeding, and untimely complementary feeding. RESULTS: Nearly half (47.9%) of infants in this study were non-exclusively breastfed (n = 96). Generalized liner mixed effects models of breastfeeding practices revealed that prelacteal feeding may be a common practice in the region (43.9%, n = 98) and characterized by gender differences (p = .03). No factors evaluated were statistically significantly predictive of early initiation and untimely complementary feeding (82% and 14%, respectively). Severely food insecure mothers had more than 72% lower odds of early breastfeeding initiation, and participants who self-reported as being illiterate had 1.53 times greater odds of untimely complementary feeding (95% CI, [0.30,7.69]) followed by male children having 1.45 greater odds of being untimely complementary fed compared to female (95% CI,[0.40,5.37]). CONCLUSIONS: This study found high rates of prelacteal feeding and low prevalence of exclusive breastfeeding, with girls more likely to be exclusively breastfed. While no predictors evaluated in this multi-level framework were associated with prevalence of early initiation or complementary feeding, rates may be clinically meaningful in a region burdened by undernutrition. Findings raise questions about gendered breastfeeding norms, the under-examined role of khat consumption on infant feeding, and the complex factors that affect breastfeeding practices in this region. This information may be used to guide future research questions and inform intervention strategies.
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Lactancia Materna , Desnutrición , Lactante , Recién Nacido , Niño , Humanos , Masculino , Femenino , Etiopía/epidemiología , Fenómenos Fisiológicos Nutricionales del Lactante , MadresRESUMEN
Background: Neurological Wilson's disease (WD) presentation in the pediatric population is rare, and liver transplantation (LT) in these patients remains controversial. The aim of the present study was to assess the role of brain magnetic resonance imaging (MRI) in predicting reversion of brain lesions and neurological outcomes in pediatric WD patients after LT. Methods: Patients with confirmed WD (Leipzig score ≥4), disease onset in pediatric age (<18 years), neurological involvement, and submitted to LT were selected. Clinical records and pre- and post-LT brain MRI were evaluated. Results: Six patients met the pre-defined inclusion criteria, one of whom died shortly after LT and was excluded. The indication for LT was end-stage liver disease in two patients and neurological worsening despite optimized treatment in three patients. After LT, the neurological picture progressively improved in all patients. Pre-LT brain MRI showed T1-weighted hyperintensities in four patients, which quickly resolved afterward. T2-weighted hyperintensities were observed in four patients before LT, completely resolving in one patient, stabilizing in two, and improving in one after LT. A direct correlation could not be found between clinical and neuroradiological improvement. Progressive clinical improvement was observed even in patients with irreversible brain MRI changes. Conversely, some patients with normal MRI had only slight neurological improvement. Conclusions: The pattern of T2-weighted hyperintensities after LT was unpredictable and did not correlate with neurological outcomes, suggesting that these changes may not entail irreversible clinical damage. Therefore, brain MRI does not seem to have prognostic value for assessing clinical response to LT.
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A negativa de cobertura de tratamentos é o principal fator que leva beneficiários de planos de saúde a buscar a justiça, e o motivo central alegado pelas empresas do setor para essa recusa é o fato do tratamento pleiteado não ser contemplado no Rol de Procedimentos e Eventos em Saúde da Agência Nacional de Saúde Suplementar. Este artigo analisou a incorporação de tecnologias em saúde no Brasil, especialmente no setor de saúde suplementar, e a regulação da cobertura de tratamento para câncer pelos planos de saúde, identificando possíveis influências, bem como o sentido da atuação do Poder Judiciário na incorporação de quimioterápicos na saúde suplementar. Para tanto, utilizaram-se dois bancos de dados que, somados, contêm informações sobre todos os acórdãos (1.368), proferidos em segunda instância entre 2015 e 2019 pelo Tribunal de Justiça do Estado de São Paulo, em ações judiciais ajuizadas na Comarca da Capital que demandaram tratamentos quimioterápicos contra operadoras de planos de saúde. Foram explorados em maior detalhe os casos dos dez quimioterápicos mais demandados no escopo considerado. Os resultados do estudo mostraram que, apesar da regulação setorial da saúde suplementar determinar a cobertura de sete dos dez quimioterápicos mais demandados, isso não impediu que ela fosse, ainda assim, negada aos beneficiários. Há, portanto, indicativos de que a atuação do Poder Judiciário, que julgou favoravelmente 96,3% das demandas analisadas, cumpre uma função de enforcement da regulação setorial da incorporação de tecnologias, em contraposição à hipótese de que seria uma via ilegítima para o acesso a tecnologias não cobertas. Trata-se, a partir dessa perspectiva, de uma importante instância de garantia do direito à saúde dos beneficiários de planos privados de saúde.
Coverage denial of health treatment is the leading cause of litigations against insurers, whose main reason alleged for such refusals is the fact that the requested treatment is not included in the List of Procedures and Events in Health of the Brazilian Regulatory Agency for Private Health Insurance and Plans. This paper analyzed the incorporation of health Technologies in Brazil, especially in supplementary private health insurance, and the regulation of câncer treatment coverage by health plans, identifying possible influences and the meaning of judicial rulings over the incorporation of chemotherapy technologies in supplementary private health insurance. For this purpose, the analysis used two databases, which together contain information on all judgements (1.368) issued between 2015 and 2019 by the São Paulo State Court of Justice on lawsuits filed in the capital's judicial district that required private chemotherapy coverage. Cases of the ten most required chemotherapeutics were explored in greater detail. Results showed that, although sectorial regulation determines that seven out of the ten most required chemotherapeutics be covered by insurers, this did not prevent coverage denial from happening. This indicates that the judicial rulings, which judged favorably 96.3% of the claims, fulfil an enforcement function regarding sectorial regulation on technology incorporation, as opposed to the hypothesis that judicialization would be an illegitimate via to access non-covered health technologies. From this perspective, judicialization is an important instance of guaranteeing the right to health for private health insurance beneficiaries.
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Judicialización de la SaludRESUMEN
Background: Infants in the neonatal intensive care unit (NICU) often require feeding tubes (FT) for weeks to months. Because FTs are in near constant contact with human milk and/or formula, rapid and extensive bacterial growth is possible. Due to their immature immunologic and gastrointestinal (GI) systems, infants may be at significant health risk due to FT colonization. In adults, length of time FTs remain in place (dwell time) affects the degree of colonization and biofilm formation which is important in infants whose tubes remain in place up to 30 days. Objective: The purpose of this review was to describe and summarize the evidence regarding FT bacterial colonization in infants and identify gaps needing further investigation. Methods: Medline, CINAHL, and Embase databases were searched for clinical and/or laboratory-based observational and randomized controlled studies investigating the presence of bacteria in neonatal FTs. Results: This review of 10 studies found evidence that neonatal FTs may contain high quantities of potentially pathogenic and antibiotic resistant bacteria and longer dwell times may increase the bacterial load. Furthermore, evidence suggests FT colonization may be nosocomial in origin and contribute to adverse infant health. Feeding tubes are an unrecognized source of bacterial colonization which may increase morbidity in premature infants and thus the presence of bacteria in FTs is an important area of investigation in the nutritional care of vulnerable infants in the NICU. Implications: Further appropriately powered studies which are clinically based, use appropriate analyses, and control for potential covariates are necessary to make clinical recommendations.
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alfa-Manosidosis , Medios de Contraste , Humanos , Imagen por Resonancia Magnética , TálamoAsunto(s)
Distonía , Trastornos Distónicos , Distonía/genética , Humanos , Factor de Transcripción YY1RESUMEN
L-2-hydroxiglutaric aciduria (L2HGA) is a rare, childhood-onset, organic aciduria, with characteristic clinical (cerebellar ataxia) and neuroimaging (subcortical leukodystrophy) features. Movement disorders in this condition are usually of hyperkinetic type. Herein is reported the case of two adult siblings with recent L2HGA diagnosis, presenting with dopa-responsive parkinsonism and MRI iron deposition.
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Encefalopatías Metabólicas Innatas/complicaciones , Encéfalo/patología , Trastornos del Metabolismo del Hierro/genética , Trastornos Parkinsonianos/genética , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , LinajeRESUMEN
BACKGROUND: Mother's own milk (MOM) is well known to decrease prematurity-related morbidities, yet mothers delivering preterm infants often produce insufficient quantities of milk to provide these benefits. Although a critical need exists for research to support lactation success in this vulnerable population, development and investigation of interventions to increase available MOM for infant consumption requires consistent, valid, and reliable measures of lactation outcomes. OBJECTIVES: The aim of this study was to compare and contrast methods of measuring lactation outcomes in mothers of preterm infants and evaluate their advantages and disadvantages. METHODS: Measures of lactation outcomes were reviewed and synthesized. Insights on best practices and future research directions are provided. RESULTS: Volume of MOM produced, lactation duration, and time to onset of secretory activation are important measures of lactation success. The most valid and reliable measure of milk production is likely weighing each vial of expressed milk combined with test weighing when infants breastfeed. Measures of lactation duration should include actual days mothers lactated rather than limiting to infant consumption of MOM as a proxy for duration and include not only whether mothers are lactating at infant discharge but whether they are also lactating at other health-relevant time points during hospitalization. Although time to onset of secretory activation is an important lactation outcome, information regarding valid and reliable indicators of onset in women delivering preterm infants is limited, and investigation of such indicators is a research priority. Variables that may affect lactation outcomes, including time to initiation of expression following delivery, duration of expression sessions, expression method, time spent in skin-to-skin care, maternal demographics and comorbidities, as well as maternal intent to lactate, must be considered when researchers investigate lactation outcomes in mothers of very low birth weight infants. DISCUSSION: Consistent and valid measures of lactation outcomes are required to produce reliable results from which evidence-based practice recommendations can be developed in order to improve lactation success in this vulnerable population.