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1.
J Am Acad Dermatol ; 90(4): 731-738, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38043592

RESUMEN

BACKGROUND: Immunosuppression is a known risk factor for the development of cutaneous squamous cell carcinoma (CSCC), especially in solid organ transplant recipients and chronic lymphocytic leukemia. However, this risk is less well defined in autoimmune and inflammatory conditions. OBJECTIVE: Assess the impact that disease-type, duration of immunosuppression, and systemic medications have on CSCC accrual rates, defined as the number of CSCCs a patient develops per year, in autoimmune and inflammatory conditions. METHODS: Retrospective review of 94 immunosuppressed (rheumatoid arthritis: 31[33.0%], inflammatory bowel disease: 17[18.1%], psoriasis: 11[11.7%], autoimmune other (AO): 24[25.5%], inflammatory other: 21[22.3%]) and 188 immunocompetent controls to identify all primary, invasive CSCCs diagnosed from 2010 to 2020. RESULTS: Immunosuppressed patients had higher CSCC accrual rates than immunocompetent controls (0.44 ± 0.36): total cohort (0.82 ± 0.95, P < .01), rheumatoid arthritis (0.88 ± 1.10, P < .01), inflammatory bowel disease (0.94 ± 0.88, P < .01), psoriasis (1.06 ± 1.58, P < .01), AO (0.72 ± 0.56, P < .01), and inflammatory other (0.72 ± 0.61, P < .01). There was an association between increased tumor accrual rates and exposure to systemic medications including, immunomodulators, tumor necrosis factor-alpha inhibitors, non-tumor necrosis factor inhibitor biologics, and corticosteroids, but not with number of systemic medication class exposures or duration of immunosuppression. LIMITATIONS: Retrospective, singlecenter study. CONCLUSION: Patients with autoimmune and inflammatory conditions accrue CSCCs at higher rates than immunocompetent patients.


Asunto(s)
Artritis Reumatoide , Carcinoma de Células Escamosas , Enfermedades Inflamatorias del Intestino , Psoriasis , Neoplasias Cutáneas , Humanos , Carcinoma de Células Escamosas/patología , Estudios Retrospectivos , Neoplasias Cutáneas/patología , Psoriasis/tratamiento farmacológico , Psoriasis/epidemiología , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/epidemiología
2.
J Am Acad Dermatol ; 90(3): 545-551, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37949119

RESUMEN

BACKGROUND: Metastatic basal cell carcinoma (mBCC) is rare and there are limited data regarding patient and tumor risk factors, optimal treatments, and disease prognosis. OBJECTIVE: To assess patient and tumor characteristics, therapeutics, and outcomes of mBCC stratified by location of metastasis. METHODS: Retrospective cohort study of 53 patients with mBCC treated at 4 large academic centers in Boston, Massachusetts; Philadelphia, Pennsylvania; and Cleveland, Ohio between January 1, 2005 and December 31, 2021. RESULTS: A total of 53 patients with mBCC were identified across 4 centers, 22 (42%) of whom had mBCC with spread limited to lymph nodes and 31 (58%) patients with distant organ spread (with or without lymph node involvement). Overall, half (n = 11) of patients with nodal metastasis achieved complete remission of disease, compared with just 1 (3%) patient with distant metastasis. The 5-year survival for nodal and distant metastatic patients was 89.3% and 61.0%, respectively. LIMITATIONS: Small sample size due to disease rarity. CONCLUSIONS AND RELEVANCE: Patients with nodal disease are more likely to have disease remission whereas patients with distant metastasis are more likely to have persistent disease and die from their disease. However, 5-year survival rates exceed 50%, even for stage IV disease.


Asunto(s)
Carcinoma Basocelular , Neoplasias Cutáneas , Humanos , Neoplasias Cutáneas/terapia , Neoplasias Cutáneas/patología , Estudios Retrospectivos , Carcinoma Basocelular/patología , Pronóstico , Ganglios Linfáticos/patología , Factores de Riesgo , Philadelphia
3.
Thorax ; 78(10): 1011-1018, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37451864

RESUMEN

INTRODUCTION: People with cystic fibrosis (CF) are often on multiple long-term treatments, including mucoactive nebulisers. In the UK, the most common mucoactive nebuliser is dornase alfa (DNase). A common therapeutic approach for people already on DNase is to add hypertonic saline (HS). The effects of DNase and HS used alone have been studied in randomised trials, but their effects in combination have not. This study investigates whether, for people already prescribed DNase, adding HS has additional benefit for lung function or use of intravenous antibiotics. METHODS: Using UK CF Registry data from 2007 to 2018, we emulated a target trial. We included people aged 6 years and over who were prescribed DNase without HS for 2 years. We investigated the effects of combinations of DNase and HS over 5 years of follow-up. Inverse-probability-of-treatment weighting was used to control confounding. The period predated triple combination CF transmembrane conductance regulator modulators in routine care. RESULTS: 4498 individuals were included. At baseline, average age and forced expiratory volume in 1 s (FEV1%) predicted were 21.1 years and 69.7 respectively. During first year of follow-up, 3799 individuals were prescribed DNase alone; 426 added HS; 57 switched to HS alone and 216 were prescribed neither. We found no evidence that adding HS improved FEV1% at 1-5 years, or use of intravenous antibiotics at 1-4 years, compared with DNase alone. CONCLUSION: For individuals with CF prescribed DNase, we found no evidence that adding HS had an effect on FEV1% or prescription of intravenous antibiotics. Our study illustrates the emulated target trial approach using CF Registry data.


Asunto(s)
Fibrosis Quística , Humanos , Fibrosis Quística/tratamiento farmacológico , Datos de Salud Recolectados Rutinariamente , Nebulizadores y Vaporizadores , Administración por Inhalación , Volumen Espiratorio Forzado , Solución Salina Hipertónica/uso terapéutico
4.
Perfusion ; 38(8): 1568-1576, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-36036658

RESUMEN

BACKGROUND: Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) flows are titrated to achieve adequate perfusion while attempting to ideally maintain arterial pulse pressure (PP). We assessed risk in patients with low PP defined as <10 mmHg within the first 2 days of support. METHODS: Demographics, haemodynamics, echocardiographic and radiological findings were recorded retrospectively in cases conducted between 2014 and 2016. Outcomes were hospital mortality, requirement for renal replacement therapy (RRT) and severe pulmonary oedema (PO). RESULTS: Of 101 patients, 66.3% were male, mean age was 56 (range 18-71 years), mean duration of support was 6.3 days ± 4.1 days, 37.6% died prior to hospital discharge, 39.6% needed RRT and 11.9% had severe PO. Areas under the receiver operating curves of PP at 48 h for hospital mortality, RRT and severe PO were (respectively): 0.69 (95% CI 0.58-0.80, p = .001), 0.64 (95% CI 0.50-0.77, p = .044), 0.69 (95% CI 0.55-0.82, p = .009). The odds ratio for mortality, RRT, severe PO for those with low PP were (respectively) 2.8 (95% CI 1.01-7.5, p = .04), 3.1 (95% CI 1.11-8.40, p = .026), 7.6 (95% CI 2.06-27.89, p = .001). Central venous pressure, mean arterial pressure were not predictive. CONCLUSION: PP during the first 2 days of support is predictive of clinically important outcomes in patients supported with VA-ECMO.


Asunto(s)
Oxigenación por Membrana Extracorpórea , Enfermedades Renales , Edema Pulmonar , Humanos , Masculino , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Femenino , Presión Sanguínea , Oxigenación por Membrana Extracorpórea/efectos adversos , Edema Pulmonar/etiología , Edema Pulmonar/terapia , Estudios Retrospectivos , Alta del Paciente , Diálisis Renal , Hospitales
5.
Thorax ; 77(9): 873-881, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-34556554

RESUMEN

BACKGROUND: Cystic fibrosis (CF) is a life-threatening genetic disease, affecting around 10 500 people in the UK. Precision medicines have been developed to treat specific CF-gene mutations. The newest, elexacaftor/tezacaftor/ivacaftor (ELEX/TEZ/IVA), has been found to be highly effective in randomised controlled trials (RCTs) and became available to a large proportion of UK CF patients in 2020. Understanding the potential health economic impacts of ELEX/TEZ/IVA is vital to planning service provision. METHODS: We combined observational UK CF Registry data with RCT results to project the impact of ELEX/TEZ/IVA on total days of intravenous (IV) antibiotic treatment at a population level. Registry data from 2015 to 2017 were used to develop prediction models for IV days over a 1-year period using several predictors, and to estimate 1-year population total IV days based on standards of care pre-ELEX/TEZ/IVA. We considered two approaches to imposing the impact of ELEX/TEZ/IVA on projected outcomes using effect estimates from RCTs: approach 1 based on effect estimates on FEV1% and approach 2 based on effect estimates on exacerbation rate. RESULTS: ELEX/TEZ/IVA is expected to result in significant reductions in population-level requirements for IV antibiotics of 16.1% (~17 800 days) using approach 1 and 43.6% (~39 500 days) using approach 2. The two approaches require different assumptions. Increased understanding of the mechanisms through which ELEX/TEZ/IVA acts on these outcomes would enable further refinements to our projections. CONCLUSIONS: This work contributes to increased understanding of the changing healthcare needs of people with CF and illustrates how Registry data can be used in combination with RCT evidence to estimate population-level treatment impacts.


Asunto(s)
Fibrosis Quística , Aminofenoles/uso terapéutico , Antibacterianos/uso terapéutico , Benzodioxoles/uso terapéutico , Fibrosis Quística/tratamiento farmacológico , Fibrosis Quística/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Humanos , Mutación , Estudios Observacionales como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Sistema de Registros
6.
Artif Organs ; 46(1): 50-56, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34580890

RESUMEN

BACKGROUND: BiVACOR is a novel total artificial heart (TAH) utilizing a single centrifugal magnetically levitated rotor with the ability to modulate pulsatile flow. The device has been successfully tested in a bovine model. We undertook a multicenter anatomical and virtual fitting study of the BiVACOR in patients undergoing heart transplantation. METHODS: 10 patients were recruited across two heart transplant centers. A sterilized 1:1 titanium model of the device was inserted into the patient's chest post heart explant, prior to implantation of the donor heart. Measurements were recorded in situ. The device was then removed. Following this, retrospective 3D reconstructions were created from computed tomography chest scans to simulate a virtual fitting. RESULTS: Mean age was 53 years (range 38-67). Mean BMI was 28 (range 20-37). Heart failure etiology was varied-with ischemic cardiomyopathy being the most common. Mean spine-to-sternum distance at the tenth thoracic vertebrae (T10) was 14 cm (range 11-18). Mean aorta to aortic Port distance was 0.2 cm (range 0-0.5). Mean pulmonary artery to pulmonary artery port distance was 4.2 cm (range 1-7). The device fitted suitably in all patients without gross distortion to the geometry between native vessel/chamber and port. CONCLUSIONS: This study described the anatomical and virtual fitting of the BiVACOR TAH. The device fit well within the chest cavities of all 10 patients, who represented a variety of body morphologies and heart failure etiology.


Asunto(s)
Corazón Artificial , Corazón/anatomía & histología , Adulto , Anciano , Femenino , Corazón/diagnóstico por imagen , Insuficiencia Cardíaca/cirugía , Trasplante de Corazón , Humanos , Masculino , Persona de Mediana Edad , Tórax/anatomía & histología , Tórax/diagnóstico por imagen , Tomografía Computarizada por Rayos X
7.
BMC Geriatr ; 22(1): 783, 2022 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-36203156

RESUMEN

BACKGROUND: Anticholinergic medications are drugs that block cholinergic transmission, either as their primary therapeutic action or as a secondary effect. Patients with dementia may be particularly sensitive to the central effects of anticholinergic drugs. Anticholinergics also antagonise the effects of the main dementia treatment, cholinesterase inhibitors. Our study aimed to investigate anticholinergic prescribing for dementia patients in UK acute hospitals before and after admission. METHODS: We included 352 patients with dementia from 17 UK hospital sites in 2019. They were all inpatients on surgical, medical or Care of the Elderly wards. Information about each patient's medications were collected using a standardised form, and the anticholinergic drug burden of each patient was calculated with an evidence-based online calculator. Wilcoxon's rank test was used to look at the correlation between two subgroups upon admission and discharge. RESULTS: On admission to hospital, 37.8% of patients had an anticholinergic burden score ≥ 1 and 5.68% ≥3. On discharge, 43.2% of patients with an anticholinergic burden score ≥ 1 and 9.1% ≥3. The increase in scores was statistically significant (p = 0.001). Psychotropics were the most common group of anticholinergic medications prescribed at discharge. Of those patients taking cholinesterase inhibitors, 44.9% were also prescribed anticholinergic medications. CONCLUSIONS: Our cross-sectional, multicentre study found that people with dementia are commonly prescribed anticholinergic medications, even if concurrently taking cholinesterase inhibitors, and are significantly more likely to be discharged from hospital with a higher anticholinergic burden than on admission.


Asunto(s)
Inhibidores de la Colinesterasa , Demencia , Anciano , Antagonistas Colinérgicos/efectos adversos , Inhibidores de la Colinesterasa/uso terapéutico , Estudios Transversales , Demencia/inducido químicamente , Demencia/tratamiento farmacológico , Demencia/epidemiología , Hospitales , Humanos
8.
Med J Aust ; 214(1): 40-44, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33040381

RESUMEN

INTRODUCTION: Coronavirus disease 2019 (COVID-19) is a contagious disease that is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Health care workers are at risk of infection from aerosolisation of respiratory secretions, droplet and contact spread. There are a number of procedures that represent a high risk of aerosol generation during cardiothoracic surgery. It is important that adequate training, equipment and procedures are in place to reduce that risk. RECOMMENDATIONS: We provide a number of key recommendations, which reduce the risk of aerosol generation during cardiothoracic surgery and help protect patients and staff. These include general measures such as patient risk stratification, appropriate use of personal protective equipment, consideration to delay surgery in positive patients, and careful attention to theatre planning and preparation. There are also recommended procedural interventions during airway management, transoesophageal echocardiography, cardiopulmonary bypass, chest drain management and specific cardiothoracic surgical procedures. Controversies exist regarding the management of low risk patients undergoing procedures at high risk of aerosol generation, and recommendations for these patients will change depending on the regional prevalence, risk of community transmission and the potential for asymptomatic patients attending for these procedures. CHANGES IN MANAGEMENT AS A RESULT OF THIS STATEMENT: This statement reflects changes in management based on expert opinion, national guidelines and available evidence. Our knowledge with regard to COVID-19 continues to evolve and with this, guidance may change and develop. Our colleagues are urged to follow national guidelines and institutional recommendations regarding best practices to protect their patients and themselves. ENDORSED BY: Australian and New Zealand Society of Cardiac and Thoracic Surgeons and the Anaesthetic Continuing Education Cardiac Thoracic Vascular and Perfusion Special Interest Group.


Asunto(s)
Aerosoles , COVID-19/prevención & control , Control de Infecciones/métodos , Transmisión de Enfermedad Infecciosa de Paciente a Profesional/prevención & control , SARS-CoV-2 , Anestesia , Australia , COVID-19/epidemiología , COVID-19/transmisión , Procedimientos Quirúrgicos Cardíacos , Consenso , Personal de Salud/educación , Humanos , Nueva Zelanda , Sociedades Médicas , Procedimientos Quirúrgicos Torácicos
9.
Exp Physiol ; 105(11): 1960-1970, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32857874

RESUMEN

NEW FINDINGS: What is the central question of this study? Do highly trained male endurance athletes who develop exercise-induced arterial hypoxaemia (EIAH) demonstrate reduced peripheral chemoresponsiveness during exercise? What is the main finding and its importance? Those with the lowest arterial saturation during exercise have a smaller ventilatory response to hypercapnia during exercise. There was no significant relationship between the hyperoxic ventilatory response and EIAH. The findings suggest that peripheral chemoresponsiveness to hypercapnia during exercise could play a role in the development of EIAH. The findings improve our understanding of the mechanisms that contribute to EIAH. ABSTRACT: Exercise-induced arterial hypoxaemia (EIAH) is characterized by a decrease in arterial oxygen tension and/or saturation during whole-body exercise, which may in part result from inadequate alveolar ventilation. However, the role of peripheral chemoresponsiveness in the development of EIAH is not well established. We hypothesized that those with the most severe EIAH would have an attenuated ventilatory response to hyperoxia and hypercapnia during exercise. To evaluate this, on separate days, we measured ventilatory sensitivity to hyperoxia and separately hypercapnia at rest and during three different exercise intensities (25, 50% of V̇O2max and ventilatory threshold (∼67% of V̇O2max )) in 12 males cyclists ( V̇O2max  = 66.6 ± 4.7 ml kg-1  min-1 ). Subjects were divided into two groups based on their end-exercise arterial oxygen saturation (ear oximetry, SpO2 ): a normal oxyhaemoglobin saturation group (NOS, SpO2  = 93.4 ± 0.4%, n = 5) and a low oxyhaemoglobin saturation group (LOS, SpO2  = 89.9 ± 0.9%, n = 7). There was no difference in V̇O2max (66.4 ± 2.9 vs. 66.8 ± 6.0 ml kg-1  min-1 , respectively, P = 0.9), peak ventilation during maximal exercise (182 ± 15 vs. 197 ± 32 l min-1 , respectively, P = 0.36) or ventilatory response to hyperoxia (P = 0.98) at any exercise intensity between NOS and LOS groups. However, those in the LOS group had a significantly lower ventilatory response to hypercapnia (P = 0.004, (η2  = 0.18). There was also a significant relationship between the mean hypercapnic response and end-exercise SpO2 (r = 0.75, P = 0.009) but not between the mean hyperoxic response and end-exercise SpO2 (r = 0.21, P = 0.51). A blunted hypercapnic ventilatory response may contribute to EIAH in highly trained men due to a failure to increase ventilation sufficiently to offset exercise-induced gas exchange impairments.


Asunto(s)
Ejercicio Físico , Consumo de Oxígeno , Atletas , Ejercicio Físico/fisiología , Humanos , Hipercapnia , Hipoxia , Masculino , Oxígeno , Consumo de Oxígeno/fisiología
10.
Am J Obstet Gynecol ; 223(5): 737.e1-737.e10, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32497612

RESUMEN

BACKGROUND: Infertility is a common presentation of female genital tuberculosis in endemic areas. Female genital tuberculosis-related maternal and neonatal complications have increased in recent years after assisted reproductive technology treatments. Despite rising emigration rates to the United States, guidelines to identify those with latent tuberculosis or female genital tuberculosis in fertility centers do not exist. OBJECTIVE: This study aimed to characterize the prevalence of female genital tuberculosis in infertile patients at our academic fertility center. STUDY DESIGN: This is a prospective cohort study. All patients presenting for infertility evaluation between January 2014 and January 2017 were assessed for risk factors for latent tuberculosis. Patients at risk for latent tuberculosis underwent screening using QuantiFERON-TB Gold serum assay. QuantiFERON-TB Gold-positive patients underwent further testing for female genital tuberculosis consisting of endometrial biopsy with histopathologic examination by a clinical pathologist, polymerase chain reaction for tuberculosis, and culture for acid-fast Mycobacterium tuberculosis. RESULTS: Twenty-five of 323 infertility patients (7.7%) screened for latent tuberculosis had positive QuantiFERON-TB Gold results. A greater number of patients with a positive test result for QuantiFERON-TB Gold were foreign born than those with a negative test result for QuantiFERON-TB Gold (92% vs 29%; P<.001). Of note, the QuantiFERON-TB Gold-positive population had a higher incidence of both recurrent pregnancy loss (28% vs 7%; P=.003) and Asherman syndrome (8% vs 0.3%; P<.001). Among those with a positive test result for QuantiFERON-TB Gold, chest x-ray was abnormal in only 2 patients (8.0%). Endometrium evaluation revealed abnormalities in 2 patients (8.0%), in whom chest x-ray was normal, with 1 showing evidence of female genital tuberculosis. This was indicated by histology consistent with chronic granulomatous endometritis and positive endometrial testing for tuberculosis by polymerase chain reaction, acid-fast bacilli smear, and culture for Mycobacterium tuberculosis. CONCLUSION: Although the prevalence of female genital tuberculosis in infertile women in the United States seems to be low, this study indicates that it can be underdiagnosed without utilization of multiple diagnostic modalities including endometrial sampling. Given the potential for serious maternal and neonatal morbidity in affected patients utilizing assisted reproductive technology, we propose that all at-risk women seeking infertility care in the United States be screened for latent tuberculosis. In patients who screen positive, endometrial biopsy should be obtained for evaluation by histology, polymerase chain reaction, and culture for Mycobacterium tuberculosis to rule out female genital tuberculosis before infertility treatments are initiated.


Asunto(s)
Endometritis/epidemiología , Infertilidad Femenina/epidemiología , Tuberculosis Latente/epidemiología , Tuberculosis de los Genitales Femeninos/epidemiología , Aborto Habitual/epidemiología , Centros Médicos Académicos , Adulto , Endometritis/diagnóstico , Endometritis/microbiología , Endometritis/patología , Endometrio/microbiología , Endometrio/patología , Femenino , Clínicas de Fertilidad , Ginatresia/epidemiología , Humanos , Incidencia , Ensayos de Liberación de Interferón gamma , Tuberculosis Latente/diagnóstico , Tamizaje Masivo , Mycobacterium tuberculosis/genética , Reacción en Cadena de la Polimerasa , Estudios Prospectivos , Tuberculosis de los Genitales Femeninos/diagnóstico , Estados Unidos/epidemiología , Adulto Joven
11.
BMC Med Res Methodol ; 20(1): 132, 2020 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-32460872

RESUMEN

BACKGROUND: Propensity scores are widely used to deal with confounding bias in medical research. An incorrectly specified propensity score model may lead to residual confounding bias; therefore it is essential to use diagnostics to assess propensity scores in a propensity score analysis. The current use of propensity score diagnostics in the medical literature is unknown. The objectives of this study are to (1) assess the use of propensity score diagnostics in medical studies published in high-ranking journals, and (2) assess whether the use of propensity score diagnostics differs between studies (a) in different research areas and (b) using different propensity score methods. METHODS: A PubMed search identified studies published in high-impact journals between Jan 1st 2014 and Dec 31st 2016 using propensity scores to answer an applied medical question. From each study we extracted information regarding how propensity scores were assessed and which propensity score method was used. Research area was defined using the journal categories from the Journal Citations Report. RESULTS: A total of 894 papers were included in the review. Of these, 187 (20.9%) failed to report whether the propensity score had been assessed. Commonly reported diagnostics were p-values from hypothesis tests (36.6%) and the standardised mean difference (34.6%). Statistical tests provided marginally stronger evidence for a difference in diagnostic use between studies in different research areas (p = 0.033) than studies using different propensity score methods (p = 0.061). CONCLUSIONS: The use of diagnostics in the propensity score medical literature is far from optimal, with different diagnostics preferred in different areas of medicine. The propensity score literature may improve with focused efforts to change practice in areas where suboptimal practice is most common.


Asunto(s)
Publicaciones Periódicas como Asunto , Sesgo , Humanos , Puntaje de Propensión , Publicaciones , Proyectos de Investigación
12.
Stat Med ; 38(26): 5120-5132, 2019 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-31512265

RESUMEN

Overcoming bias due to confounding and missing data is challenging when analyzing observational data. Propensity scores are commonly used to account for the first problem and multiple imputation for the latter. Unfortunately, it is not known how best to proceed when both techniques are required. We investigate whether two different approaches to combining propensity scores and multiple imputation (Across and Within) lead to differences in the accuracy or precision of exposure effect estimates. Both approaches start by imputing missing values multiple times. Propensity scores are then estimated for each resulting dataset. Using the Across approach, the mean propensity score across imputations for each subject is used in a single subsequent analysis. Alternatively, the Within approach uses propensity scores individually to obtain exposure effect estimates in each imputation, which are combined to produce an overall estimate. These approaches were compared in a series of Monte Carlo simulations and applied to data from the British Society for Rheumatology Biologics Register. Results indicated that the Within approach produced unbiased estimates with appropriate confidence intervals, whereas the Across approach produced biased results and unrealistic confidence intervals. Researchers are encouraged to implement the Within approach when conducting propensity score analyses with incomplete data.


Asunto(s)
Sesgo , Puntaje de Propensión , Algoritmos , Intervalos de Confianza , Interpretación Estadística de Datos , Modelos Estadísticos , Método de Montecarlo , Estudios Observacionales como Asunto/estadística & datos numéricos
16.
Clin Obstet Gynecol ; 62(2): 238-256, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30994481

RESUMEN

Anti-Müllerian hormone (AMH) has become one of the most informative biochemical markers of the ovary and is considered the earliest and most sensitive marker of reproductive aging. The accuracy of AMH in predicting ovarian response to controlled ovarian stimulation has led to AMH-based prognostication counseling and individualization of assisted reproductive technology (ART) stimulation protocols to optimize ovarian response and minimize hyperstimulation risks. Although AMH is considered a good predictor of quantitative ART outcomes, its correlation with qualitative ART outcomes is still controversial. The aim of this review is to provide an updated overview of the clinical utility of AMH in predicting ART outcomes.


Asunto(s)
Hormona Antimülleriana/sangre , Técnicas Reproductivas Asistidas , Aborto Espontáneo/sangre , Biomarcadores/sangre , Relación Dosis-Respuesta a Droga , Embrión de Mamíferos , Femenino , Gonadotropinas/administración & dosificación , Humanos , Nacimiento Vivo , Oocitos/citología , Síndrome de Hiperestimulación Ovárica/sangre , Síndrome de Hiperestimulación Ovárica/diagnóstico , Reserva Ovárica , Inducción de la Ovulación , Embarazo
20.
Eur J Public Health ; 27(suppl_2): 107-111, 2017 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-28402410

RESUMEN

Background: Engaging in regular physical activity has a beneficial impact on both physical health and on subjective health indicators. The aims of this study were (i) to assess the association between physical activity levels and self-reported health status in European adolescents and (ii) to identify any differences in the distribution of adolescents reporting good health between active and inactive subjects across urban areas. The study sample comprised 13 783 15-year olds from 21 urban areas across Europe who participated in the European Urban Health Indicators System Part 2 youth survey in 2010/11. Data collected on physical activity levels, self-rated health status and covariates including gender, BMI, socioeconomic status and sedentary behaviour were analyzed in a multivariable logistic regression model. High levels of physical activity (OR: 1.607, 95% CI: 1.245-2.074, P < 0.001) were associated with self-rated 'good health' across the cohort as a whole. All cities except Iasi showed a positive association between high levels of physical activity and good health. This was significant in four cases: Amsterdam, Cardiff, Greater Manchester and Merseyside ( P = 0.035, 0.016, 0.010 and 0.049, respectively). Only 13.3% of the cohort met the current WHO physical activity level recommendations. High levels of physical activity are positively associated with self-rated 'good health' status in European adolescents. Alarming levels of physical inactivity make it a priority to encourage greater engagement in physical activity. Promotion of physical activity should be specifically tailored to each urban area.


Asunto(s)
Ejercicio Físico , Estado de Salud , Adolescente , Salud del Adolescente/estadística & datos numéricos , Europa (Continente)/epidemiología , Femenino , Humanos , Masculino , Autoinforme , Factores Socioeconómicos , Encuestas y Cuestionarios
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