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1.
Sci Adv ; 10(13): eadm8825, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38552010

RESUMEN

Effective thermal management of electronic devices encounters substantial challenges owing to the notable power densities involved. Here, we propose layered MoS2 phononic crystals (PnCs) that can effectively reduce thermal conductivity (κ) with relatively small disruption of electrical conductivity (σ), offering a potential thermal management solution for nanoelectronics. These layered PnCs exhibit remarkable efficiency in reducing κ, surpassing that of Si and SiC PnCs with similar periodicity by ~100-fold. Specifically, in suspended MoS2 PnCs, we measure an exceptionally low κ down to 0.1 watts per meter kelvin, below the amorphous limit while preserving the crystalline structure. These findings are supported by molecular dynamics simulations that account for the film thickness, porosity, and temperature. We demonstrate the approach efficiency by fabricating suspended heat-routing structures that effectively confine and guide heat flow in prespecified directions. This study underpins the immense potential of layered materials as directional heat spreaders, thermal insulators, and active components for thermoelectric devices.

2.
Curr Oncol ; 30(7): 6559-6574, 2023 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-37504341

RESUMEN

Lorlatinib is the only targeted therapy approved in Canada to treat patients with anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer (NSCLC) whose tumor has progressed despite treatment with second-generation ALK tyrosine kinase inhibitor (TKI), a patient population with high unmet need and lack of publicly reimbursed targeted treatments in Canada. We prospectively examined the real-world effectiveness and impact of lorlatinib on quality-of-life in 59 lorlatinib-treated patients, characterized as: median age of 62.0 years; 47.5% were female; 32.2% had central nervous system metastases; 50.8% had 2+ prior ALK TKI lines; and alectinib was the most common ALK TKI (72.9%) administered before lorlatinib, including 44.1% who received first-line alectinib. With a median follow-up of 15.3 months (IQR: 6.2-19.2), median time-to-treatment discontinuation of lorlatinib was 15.3 months (95% CI: 7.9-not reached), with 54.2% (95% CI: 40.8-65.9%) of patients without treatment discontinuation at 12 months. At baseline, the mean health utility score (HUS) was 0.744 (SD: 0.200). At 3 months, patients receiving lorlatinib demonstrated a 0.069 (95% CI: 0.020-0.118; p = 0.007) average HUS increase over baseline; HUS was maintained at 6 and 12 months. Thus, patients with ALK-positive NSCLC post second-generation ALK TKI remained on lorlatinib for a meaningful duration of time while their quality-of-life was preserved.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Femenino , Humanos , Masculino , Persona de Mediana Edad , Quinasa de Linfoma Anaplásico/antagonistas & inhibidores , Canadá , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Lactamas Macrocíclicas/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Tirosina Quinasas , Calidad de Vida
3.
Curr Oncol ; 30(5): 4663-4676, 2023 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-37232810

RESUMEN

BACKGROUND: Many patients with advanced follicular lymphoma (FL) and marginal zone lymphoma (MZL) relapse after first-line chemotherapy. OBJECTIVE: To examine healthcare resource utilization (HCRU) and cost, treatment patterns, progression, and survival of patients with FL and MZL who relapse after first-line treatment, in Ontario, Canada. METHODS: A retrospective, administrative data study identified patients with relapsed FL and MZL (1 January 2005-31 December 2018). Patients were followed for up to three years post relapse to assess HCRU, healthcare costs, time to next treatment (TTNT), and overall survival (OS), stratified by first- and second-line treatment. RESULTS: The study identified 285 FL and 68 MZL cases who relapsed after first-line treatment. Average duration of first-line treatment was 12.4 and 13.4 months for FL and MZL patients, respectively. Drug (35.9%) and cancer clinic costs (28.1%) were major contributors to higher costs in year 1. Three-year OS was 83.9% after FL and 74.2% after MZL relapse. No statistically significant differences were observed in TTNT and OS between patients with FL who received R-CHOP/R-CVP/BR in the first line only versus both the first- and second- line. A total of 31% of FL and 34% of MZL patients progressed to third-line treatment within three years of initial relapse. CONCLUSION: Relapsing and remitting nature of FL and MZL in a subset of patients results in substantial burden to patients and the healthcare system.


Asunto(s)
Linfoma de Células B de la Zona Marginal , Linfoma Folicular , Humanos , Linfoma Folicular/tratamiento farmacológico , Linfoma Folicular/epidemiología , Ontario/epidemiología , Estudios Retrospectivos , Recurrencia Local de Neoplasia/epidemiología , Linfoma de Células B de la Zona Marginal/tratamiento farmacológico , Linfoma de Células B de la Zona Marginal/epidemiología , Linfoma de Células B de la Zona Marginal/patología , Costo de Enfermedad
4.
Phys Rev Lett ; 130(10): 106903, 2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36962028

RESUMEN

Nanophononics has the potential for information transfer, in an analogous manner to its photonic and electronic counterparts. The adoption of phononic systems has been limited, due to difficulties associated with the generation, manipulation, and detection of phonons, especially at GHz frequencies. Existing techniques often require piezoelectric materials with an external radiofrequency excitation that are not readily integrated into existing CMOS infrastructures, while nonpiezoelectric demonstrations have been inefficient. In this Letter, we explore the optomechanical generation of coherent phonons in a suspended 2D silicon phononic crystal cavity with a guided mode around 6.8 GHz. By incorporating an air-slot into this cavity, we turn the phononic waveguide into an optomechanical platform that exploits localized photonic modes resulting from inherent fabrication imperfections for the transduction of mechanics. Such a platform exhibits very fine control of phonons using light, and is capable of coherent self-sustained phonon generation around 6.8 GHz, operating at room temperature. The ability to generate high frequency coherent mechanical vibrations within such a simple 2D CMOS-compatible system could be a first step towards the development of sources in phononic circuitry and the coherent manipulation of other solid-state properties.

5.
Polymers (Basel) ; 15(3)2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36771835

RESUMEN

The thermal imaging of surfaces with microscale spatial resolution over micro-sized areas remains a challenging and time-consuming task. Surface thermal imaging is a very important characterization tool in mechanical engineering, microelectronics, chemical process engineering, optics, microfluidics, and biochemistry processing, among others. Within the realm of electronic circuits, this technique has significant potential for investigating hot spots, power densities, and monitoring heat distributions in complementary metal-oxide-semiconductor (CMOS) platforms. We present a new technique for remote non-invasive, contactless thermal field mapping using synchrotron radiation-based Fourier-transform infrared microspectroscopy. We demonstrate a spatial resolution better than 10 um over areas on the order of 12,000 um2 measured in a polymeric thin film on top of CaF2 substrates. Thermal images were obtained from infrared spectra of poly(methyl methacrylate) thin films heated with a wire. The temperature dependence of the collected infrared spectra was analyzed via linear regression and machine learning algorithms, namely random forest and k-nearest neighbor algorithms. This approach speeds up signal analysis and allows for the generation of hyperspectral temperature maps. The results here highlight the potential of infrared absorbance to serve as a remote method for the quantitative determination of heat distribution, thermal properties, and the existence of hot spots, with implications in CMOS technologies and other electronic devices.

6.
Nanoscale ; 14(37): 13428-13451, 2022 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-36082529

RESUMEN

Phonons play a key role in the physical properties of materials, and have long been a topic of study in physics. While the effects of phonons had historically been considered to be a hindrance, modern research has shown that phonons can be exploited due to their ability to couple to other excitations and consequently affect the thermal, dielectric, and electronic properties of solid state systems, greatly motivating the engineering of phononic structures. Advances in nanofabrication have allowed for structuring and phonon confinement even down to the nanoscale, drastically changing material properties. Despite developments in fabricating such nanoscale devices, the proper manipulation and characterization of phonons continues to be challenging. However, a fundamental understanding of these processes could enable the realization of key applications in diverse fields such as topological phononics, information technologies, sensing, and quantum electrodynamics, especially when integrated with existing electronic and photonic devices. Here, we highlight seven of the available methods for the excitation and detection of acoustic phonons and vibrations in solid materials, as well as advantages, disadvantages, and additional considerations related to their application. We then provide perspectives towards open challenges in nanophononics and how the additional understanding granted by these techniques could serve to enable the next generation of phononic technological applications.

7.
Foods ; 11(9)2022 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-35564027

RESUMEN

The substitution of extra virgin olive oil with other edible oils is the primary method for fraud in the olive-oil industry. Developing inexpensive analytical methods for confirming the quality and authenticity of olive oils is a major strategy towards combatting food fraud. Current methods used to detect such adulterations require complicated time- and resource-intensive preparation steps. In this work, a comparative study incorporating Raman and infrared spectroscopies, photoluminescence, and thermal-conductivity measurements of different sets of adulterated olive oils is presented. The potential of each characterization technique to detect traces of adulteration in extra virgin olive oils is evaluated. Concentrations of adulterant on the order of 5% can be detected in the Raman, infrared, and photoluminescence spectra. Small changes in thermal conductivity were also found for varying amounts of adulterants. While each of these techniques may individually be unable to identify impurity adulterants, the combination of these techniques together provides a holistic approach to validate the purity and authenticity of olive oils.

8.
Nano Lett ; 21(21): 9102-9107, 2021 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-34672602

RESUMEN

Engineering of the dispersion properties of a photonic crystal (PhC) opens a new paradigm for the design and function of PhC devices. Exploiting the dispersion properties of PhCs allows control over wave propagation within a PhC. We describe the design, fabrication, and experimental observation of photonic bands for 3D PhCs capable of negative refraction in the mid-infrared. Band structure and equifrequency contours were calculated to inform the design of 3D polymer-germanium core-shell PhCs, which were fabricated using two-photon lithography direct laser writing and sputtering. We successfully characterized a polymer-Ge core-shell lattice and mapped its band structure, which we then used to calculate the PhC refraction behavior. An analysis of wave propagation revealed that this 3D core-shell PhC refracts light negatively and possesses an effective negative index of refraction in the experimentally observed region. These results suggest that architected nanolattices have the potential to serve as new optical components and devices across infrared frequencies.

9.
Sci Rep ; 11(1): 5749, 2021 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-33707480

RESUMEN

Reactive oxygen species (ROS) are implicated in triggering cell signalling events and pathways to promote and maintain tumorigenicity. Chemotherapy and radiation can induce ROS to elicit cell death allows for targeting ROS pathways for effective anti-cancer therapeutics. Coenzyme Q10 is a critical cofactor in the electron transport chain with complex biological functions that extend beyond mitochondrial respiration. This study demonstrates that delivery of oxidized Coenzyme Q10 (ubidecarenone) to increase mitochondrial Q-pool is associated with an increase in ROS generation, effectuating anti-cancer effects in a pancreatic cancer model. Consequent activation of cell death was observed in vitro in pancreatic cancer cells, and both human patient-derived organoids and tumour xenografts. The study is a first to demonstrate the effectiveness of oxidized ubidecarenone in targeting mitochondrial function resulting in an anti-cancer effect. Furthermore, these findings support the clinical development of proprietary formulation, BPM31510, for treatment of cancers with high ROS burden with potential sensitivity to ubidecarenone.


Asunto(s)
Apoptosis , Mitocondrias/metabolismo , Neoplasias Pancreáticas/patología , Especies Reactivas de Oxígeno/metabolismo , Ubiquinona/análogos & derivados , Animales , Línea Celular Tumoral , Proliferación Celular , Respiración de la Célula , Supervivencia Celular , Complejo II de Transporte de Electrones/metabolismo , Glicerol-3-Fosfato Deshidrogenasa (NAD+) , Humanos , Potencial de la Membrana Mitocondrial , Ratones Desnudos , Organoides/patología , Estrés Oxidativo , Consumo de Oxígeno , Neoplasias Pancreáticas/metabolismo , Especificidad por Sustrato , Ubiquinona/metabolismo
10.
BMJ Open ; 10(7): e037485, 2020 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-32709654

RESUMEN

OBJECTIVES: To determine the long-term trajectories of health system use by persons with dementia as they remain in the community over time. DESIGN: Population-based cohort study using health administrative data. SETTING: Ontario, Canada from 1 April 2007 to 31 March 2014. PARTICIPANTS: 62 622 community-dwelling adults aged 65+ years with prevalent dementia on 1 April 2007 matched 1:1 to persons without dementia based on age, sex and comorbidity. MAIN OUTCOME MEASURES: Rates of health service use, long-term care placement and mortality over time. RESULTS: After 7 years, 49.0% of persons with dementia had spent time in long-term care (6.8% without) and 64.5% had died (30.0% without). Persons with dementia were more likely than those without to use home care (rate ratio (RR) 3.02, 95% CI 2.93 to 3.11) and experience hospitalisations with a discharge delay (RR 2.36, 95% CI 2.30 to 2.42). As they remained in the community, persons with dementia used home care at a growing rate (10.7%, 95% CI 10.0 to 11.3 increase per year vs 6.7%, 95% CI 4.3 to 9.0 per year among those without), but rates of acute care hospitalisation remained constant (0.6%, 95% CI -0.6 to 1.9 increase per year). CONCLUSIONS: While persons with dementia used more health services than those without dementia over time, the rate of change in use differed by service type. These results, particularly enumerating the increased intensity of home care service use, add value to capacity planning initiatives where limited budgets require balancing services.


Asunto(s)
Demencia , Servicios de Atención de Salud a Domicilio , Anciano , Estudios de Cohortes , Demencia/epidemiología , Humanos , Vida Independiente , Ontario/epidemiología
11.
JAMA Netw Open ; 3(6): e204669, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32496565

RESUMEN

Importance: Predicting chronic disease incidence for the population provides a comprehensive picture to health policy makers of their jurisdictions' overall future chronic disease burden. However, no population-based risk algorithm exists for estimating the risk of first major chronic disease. Objective: To develop and validate the Chronic Disease Population Risk Tool (CDPoRT), a population risk algorithm that predicts the 10-year incidence of the first major chronic disease in the adult population. Design, Setting, and Participants: In this cohort study, CDPoRT was developed and validated with 6 cycles of the Canadian Community Health Survey, linked to administrative data from January 2000 to December 2014. Development and internal validation (bootstrap and split sample) of CDPoRT occurred in Ontario, Canada, from June 2018 to April 2019 followed by external validation in Manitoba from May 2019 to July 2019. The study cohorts included 133 991 adults (≥20 years) representative of the Ontario and Manitoba populations who did not have a history of major chronic disease. Exposures: Predictors were routinely collected risk factors from the Canadian Community Health Survey, such as sociodemographic factors (eg, age), modifiable lifestyle risk factors (ie, alcohol consumption, cigarette smoking, unhealthy diet, and physical inactivity), and other health-related factors (eg, body mass index). Main Outcomes and Measures: Six major chronic diseases were considered, as follows: congestive heart failure, chronic obstructive pulmonary disease, diabetes, myocardial infarction, lung cancer, and stroke. Sex-specific CDPoRT algorithms were developed with a Weibull model. Model performance was evaluated with measures of overall predictive performance (eg, Brier score), discrimination (eg, Harrell C index), and calibration (eg, calibration curves). Results: The Ontario cohort (n = 118 747) was younger (mean [SD] age, 45.6 [16.1] vs 46.3 [16.4] years), had more immigrants (23 808 [20.0%] vs 1417 [10.7%]), and had a lower mean (SD) body mass index (26.9 [5.1] vs 27.7 [5.4]) than the Manitoba cohort (n = 13 244). During development, the full and parsimonious CDPoRT models had similar Brier scores (women, 0.087; men, 0.091), Harrell C index values (women, 0.779; men, 0.783), and calibration curves. A simple version consisting of cigarette smoking, age, and body mass index performed slightly worse than the other versions (eg, Brier score for women, 0.088; for men, 0.092). Internal validation showed consistent performance across models, and CDPoRT performed well during external validation. For example, the female parsimonious version had C index values for bootstrap, split sample, and external validation of 0.778, 0.776, and 0.752, respectively. Conclusions and Relevance: In this study, CDPoRT provided accurate, population-based risk estimates for the first major chronic disease.


Asunto(s)
Algoritmos , Enfermedad Crónica/epidemiología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Fumar Cigarrillos , Estudios de Cohortes , Diabetes Mellitus/epidemiología , Femenino , Predicción/métodos , Encuestas Epidemiológicas , Insuficiencia Cardíaca/epidemiología , Humanos , Incidencia , Neoplasias Pulmonares/epidemiología , Masculino , Manitoba/epidemiología , Persona de Mediana Edad , Modelos Estadísticos , Infarto del Miocardio/epidemiología , Ontario/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Medición de Riesgo/métodos , Factores de Riesgo , Accidente Cerebrovascular/epidemiología , Adulto Joven
12.
Nano Lett ; 20(5): 3513-3520, 2020 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-32338926

RESUMEN

Additive manufacturing at small scales enables advances in micro- and nanoelectromechanical systems, micro-optics, and medical devices. Materials that lend themselves to AM at the nanoscale, especially for optical applications, are limited. State-of-the-art AM processes for high-refractive-index materials typically suffer from high porosity and poor repeatability and require complex experimental procedures. We developed an AM process to fabricate complex 3D architectures out of fully dense titanium dioxide (TiO2) with a refractive index of 2.3 and nanosized critical dimensions. Transmission electron microscopy (TEM) analysis proves this material to be rutile phase of nanocrystalline TiO2, with an average grain size of 110 nm and <1% porosity. Proof-of-concept woodpile architectures with 300-600 nm beam dimensions exhibit a full photonic band gap centered at 1.8-2.9 µm, as revealed by Fourier-transform infrared spectroscopy (FTIR) and supported by plane wave expansion simulations. The developed AM process enables advances in 3D MEMS, micro-optics, and prototyping of 3D dielectric PhCs.

13.
J Am Geriatr Soc ; 68(6): 1293-1300, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32119121

RESUMEN

OBJECTIVES: The main objective of the study was to investigate annual changes in the sociodemographic characteristics, morbidity, and functional status of new nursing home residents in Ontario, Canada, between 2000 and 2015. A secondary objective was to develop and assess the quality of an algorithm for ascertaining admissions into publicly funded nursing homes in Ontario using a combination of health administrative data sources that indirectly identifies the residential status of new nursing home residents. DESIGN: Population-based serial cross-sectional study with an accompanying quality assessment study of algorithms. SETTING: Publicly funded nursing care homes in Ontario, Canada. PARTICIPANTS: The reference standard for the assessment of algorithm performance was 21 544 newly admitted nursing home residents identified from the Resident Assessment Instrument-Minimum Data Set in 2012. The selected algorithm was then used to identify serial cross-sectional cohorts of newly admitted residents between 2000 and 2015 that ranged in size between 14 651 and 23 630 residents. MEASUREMENTS: Sociodemographic characteristics, morbidity, and functional status of new residents were determined upon admission to examine patterns in the cohorts' profiles. RESULTS: The proportion of residents aged 85 years and older increased from 45.1% to 53.8% over 16 years. The proportions of individuals with seven or more chronic conditions (from 14.1% to 22.1%) and with nine or more prescription medications (from 44.9% to 64.2%) have also increased in parallel over time. Hypertension, osteoarthritis, and dementia were the most prevalent conditions captured, with the proportion of incoming residents with dementia increasing from 42.3% to 54.1% between 2000 and 2015. Newly admitted residents were more likely to have extensive physical and cognitive impairments upon admission. CONCLUSION: Admission trends show that new residents were older and had greater multimorbidity and limitations in physical functioning over time. J Am Geriatr Soc 68:1293-1300, 2020.


Asunto(s)
Actividades Cotidianas/psicología , Algoritmos , Comorbilidad , Demencia/epidemiología , Casas de Salud , Admisión del Paciente/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Masculino , Ontario/epidemiología , Sector Público/economía , Factores Socioeconómicos
14.
Int J Epidemiol ; 49(1): 113-130, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31329872

RESUMEN

BACKGROUND: This study examined the incidence of a person's first diagnosis of a selected chronic disease, and the relationships between modifiable lifestyle risk factors and age to first of six chronic diseases. METHODS: Ontario respondents from 2001 to 2010 of the Canadian Community Health Survey were followed up with administrative data until 2014 for congestive heart failure, chronic obstructive respiratory disease, diabetes, lung cancer, myocardial infarction and stroke. By sex, the cumulative incidence function of age to first chronic disease was calculated for the six chronic diseases individually and compositely. The associations between modifiable lifestyle risk factors (alcohol, body mass index, smoking, diet, physical inactivity) and age to first chronic disease were estimated using cause-specific Cox proportional hazards models and Fine-Gray competing risk models. RESULTS: Diabetes was the most common disease. By age 70.5 years (2015 world life expectancy), 50.9% of females and 58.1% of males had at least one disease and few had a death free of the selected diseases (3.4% females; 5.4% males). Of the lifestyle factors, heavy smoking had the strongest association with the risk of experiencing at least one chronic disease (cause-specific hazard ratio = 3.86; 95% confidence interval = 3.46, 4.31). The lifestyle factors were modelled for each disease separately, and the associations varied by chronic disease and sex. CONCLUSIONS: We found that most individuals will have at least one of the six chronic diseases before dying. This study provides a novel approach using competing risk methods to examine the incidence of chronic diseases relative to the life course and how their incidences are associated with lifestyle behaviours.


Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Enfermedad Crónica/epidemiología , Dieta , Ejercicio Físico , Conducta Sedentaria , Fumar/efectos adversos , Adulto , Edad de Inicio , Anciano , Anciano de 80 o más Años , Consumo de Bebidas Alcohólicas/epidemiología , Índice de Masa Corporal , Enfermedades Cardiovasculares/epidemiología , Comorbilidad , Diabetes Mellitus Tipo 2/epidemiología , Femenino , Encuestas Epidemiológicas , Humanos , Incidencia , Estilo de Vida , Masculino , Persona de Mediana Edad , Obesidad/epidemiología , Ontario/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Factores de Riesgo , Fumar/epidemiología , Fumar Tabaco/efectos adversos , Fumar Tabaco/epidemiología
15.
Nat Commun ; 10(1): 4340, 2019 09 25.
Artículo en Inglés | MEDLINE | ID: mdl-31554803

RESUMEN

The coloration of some butterflies, Pachyrhynchus weevils, and many chameleons are notable examples of natural organisms employing photonic crystals to produce colorful patterns. Despite advances in nanotechnology, we still lack the ability to print arbitrary colors and shapes in all three dimensions at this microscopic length scale. Here, we introduce a heat-shrinking method to produce 3D-printed photonic crystals with a 5x reduction in lattice constants, achieving sub-100-nm features with a full range of colors. With these lattice structures as 3D color volumetric elements, we printed 3D microscopic scale objects, including the first multi-color microscopic model of the Eiffel Tower measuring only 39 µm tall with a color pixel size of 1.45 µm. The technology to print 3D structures in color at the microscopic scale promises the direct patterning and integration of spectrally selective devices, such as photonic crystal-based color filters, onto free-form optical elements and curved surfaces.

16.
CMAJ ; 191(32): E879-E885, 2019 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-31405834

RESUMEN

BACKGROUND: There is a lack of data in Canada on the longitudinal effects of adverse events that occur in hospital, specifically in the period after discharge. Our objective was to quantify the impact of adverse events on hospital length of stay, length of person-centred episodes of care (PCEs) and costs of PCEs, as well as their impact on the total health system. METHODS: We conducted a population-based, retrospective cohort study using linked health administrative databases. We included adults in Ontario who had an acute hospital admission between Apr. 1, 2015, and Mar. 31, 2016. We grouped hospital admissions into 1 of 9 episode types and used the Canadian Institute for Health Information methodology for hospital harm to measure adverse events. We specified generalized linear models to estimate the impact of hospital harm on the following: incremental length of index acute hospital admission, incremental length of the PCE, and incremental costs of the PCE. RESULTS: Out of 610 979 hospital admissions, 36 004 (5.9%) involved an occurrence of harm. The impact of harm on the incremental length of hospital stay ranged from 0.4 to 24.2 days (p < 0.001); the incremental length of the PCE ranged from 0.3 to 30.2 days (p < 0.001); and the incremental costs of the PCE ranged from $800 to $51 067 (p < 0.001). Total hospital days attributable to hospital harm amounted to 407 696, and the total attributable cost to the Ontario health system amounted to $1 088 330 376. INTERPRETATION: We found that experiencing harm in hospital significantly affects both in-hospital and post-discharge use of health services and costs of care, and constitutes an enormous expense to Ontario's publicly funded health system.


Asunto(s)
Atención Ambulatoria/economía , Costos de la Atención en Salud , Hospitalización/economía , Enfermedad Iatrogénica/economía , Adulto , Anciano , Anciano de 80 o más Años , Atención Ambulatoria/estadística & datos numéricos , Canadá , Estudios de Cohortes , Infección Hospitalaria/economía , Infección Hospitalaria/epidemiología , Episodio de Atención , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Enfermedad Iatrogénica/epidemiología , Tiempo de Internación/economía , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Ontario , Atención Dirigida al Paciente , Estudios Retrospectivos
17.
Diagn Progn Res ; 2: 4, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-31093554

RESUMEN

BACKGROUND: Prognostic models incorporating survival analysis predict the risk (i.e., probability) of experiencing a future event over a specific time period. In 2002, Royston and Parmar described a type of flexible parametric survival model called the Royston-Parmar model in Statistics in Medicine, a model which fits a restricted cubic spline to flexibly model the baseline log cumulative hazard on the proportional hazards scale. This feature permits absolute measures of effect (e.g., hazard rates) to be estimated at all time points, an important feature when using the model. The Royston-Parmar model can also incorporate time-dependent effects and be used on different scales (e.g., proportional odds, probit). These features make the Royston-Parmar model attractive for prediction, yet their current uptake for prognostic modeling is unknown. Thus, the objectives were to conduct a scoping review of how the Royston-Parmar model has been applied to prognostic models in health research, to raise awareness of the model, to identify gaps in current reporting, and to offer model building considerations and reporting suggestions for other researchers. METHODS: Five electronic databases and gray literature indexed in web sources from 2001 to 2016 were searched to identify articles for inclusion in the scoping review. Two reviewers independently screened 1429 articles, and after applying exclusion criteria through a two-step screening process, data from 12 studies were abstracted. RESULTS: Since 2001, only 12 studies were identified that used the Royston-Parmar model in some capacity for prognostic modeling, 10 of which used the model as the basis for their prognostic model. The restricted cubic spline varied across studies in the number of interior knots (range 1 to 6), and only three studies reported knot placement. Three studies provided details about the baseline function, with two studies using a figure and the third providing coefficients. However, no studies provided adequate information on their restricted cubic spline to permit others to validate or completely use the model. CONCLUSIONS: Despite the advantages of the Royston-Parmar model for prognostic models, they are not widely used in health research. Better reporting of details about the restricted cubic spline is needed, so the prognostic model can be used and validated by others. REGISTRATION: The protocol was registered with Open Science Framework (https://osf.io/r3232/).

18.
Diagn Progn Res ; 2: 19, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-31093567

RESUMEN

BACKGROUND: Population-based risk prediction tools exist for individual chronic diseases. From a population health perspective, studying chronic diseases together provides a comprehensive view of the burden of disease in the population. Thus, public health officials and health policymakers would benefit from a prediction tool that measures the incidence of chronic diseases compositely. This study protocol proposes the development and validation of the Chronic Disease Population Risk Tool (CDPoRT) that will predict the incidence of six chronic diseases in the population setting using multivariable modeling techniques. METHODS: CDPoRT will be built using population-based responses to the first six cycles of the Canadian Community Health Survey linked to health administrative data in Ontario and Manitoba from 2000 to 2014. Predictors including modifiable lifestyle risk factors (i.e., alcohol consumption, cigarette smoking, diet, and physical activity) will be used to predict time-to-chronic disease incidence (i.e., congestive heart failure, chronic obstructive pulmonary disease, diabetes, lung cancer, myocardial infarction, and stroke including transient ischemic heart attack). Sex-specific Royston-Parmar models will be used for model development and validation with death free of chronic disease as a competing risk. CDPoRT will be developed using an Ontario derivation cohort consisting of 47,960 females and 38,267 males with 7035 and 6220 chronic disease events, respectively. The model will be validated using split-sample validation using an Ontario validation cohort consisting of 20,325 females and 16,627 males with 2972 and 2658 chronic disease events, respectively. The model will be externally validated in the Manitoba validation cohort (i.e., geographic validation) expected to consist of 11,800 females and 9700 males with 1650 and 1550 chronic disease events, respectively. Measures of overall predictive accuracy (e.g., Nagelkerke's R 2), discrimination (e.g., Harrell's concordance statistic), and calibration (e.g., calibration plots) will be used to assess predictive performance. DISCUSSION: To the extent of our knowledge, CDPoRT will be the first population-based regression prediction model that will predict the incidence of multiple chronic diseases simultaneously at the population level.

19.
Q J Exp Psychol (Hove) ; 71(6): 1357-1366, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28398128

RESUMEN

Information about a group of similar objects can be summarized into a compressed code, known as ensemble coding. Ensemble coding of simple stimuli (e.g., groups of circles) can occur in the absence of detailed exemplar coding, suggesting dissociable processes. Here, we investigate whether a dissociation would still be apparent when coding facial identity, where individual exemplar information is much more important. We examined whether ensemble coding can occur when exemplar coding is difficult, as a result of large sets or short viewing times, or whether the two types of coding are positively associated. We found a positive association, whereby both ensemble and exemplar coding were reduced for larger groups and shorter viewing times. There was no evidence for ensemble coding in the absence of exemplar coding. At longer presentation times, there was an unexpected dissociation, where exemplar coding increased yet ensemble coding decreased, suggesting that robust information about face identity might suppress ensemble coding. Thus, for face identity, we did not find the classic dissociation-of access to ensemble information in the absence of detailed exemplar information-that has been used to support claims of distinct mechanisms for ensemble and exemplar coding.


Asunto(s)
Cara , Reconocimiento Visual de Modelos/fisiología , Reconocimiento en Psicología/fisiología , Adolescente , Adulto , Análisis de Varianza , Expresión Facial , Femenino , Humanos , Masculino , Estimulación Luminosa , Adulto Joven
20.
CMAJ Open ; 4(2): E240-8, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27398370

RESUMEN

BACKGROUND: Emergency department use may reflect poor access to primary care. Our objective was to compare rates and causes of emergency department use between adults living with and without HIV. METHODS: We conducted a population-based study involving Ontario residents living with and without HIV between Apr. 1, 2011, and Mar. 31, 2012. We frequency matched adults with HIV to 4 HIV-negative people by age, sex and census division, and used random-effects negative binomial regression to compare rates of emergency department use. We classified visits as low urgency or high urgency, and also examined visits for ambulatory care sensitive conditions. Hospital admission following an emergency department visit was a secondary outcome. RESULTS: We identified 14 534 people with HIV and 58 136 HIV-negative individuals. Rates of emergency department use were higher among people with HIV (67.3 v. 31.2 visits per 100 person-years; adjusted rate ratio 1.58, 95% confidence interval [CI] 1.51-1.65). Similar results were observed for low-urgency visits. With the exception of hypertension, visit rates for ambulatory care sensitive conditions were higher among people with HIV. People with HIV were also more likely than HIV-negative individuals to be admitted to hospital following an emergency department visit (adjusted odds ratio 1.55, 95% CI 1.43-1.69). INTERPRETATION: Compared with HIV-negative individuals, people with HIV had high rates of emergency department use, including potentially avoidable visits. These findings strongly support the need for comprehensive care for people with HIV.

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