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"Li, Angie"
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Improving Prediction of Survival for Extremely Premature Infants Born at 23 to 29 Weeks Gestational Age in the Neonatal Intensive Care Unit: Development and Evaluation of Machine Learning Models
Infants born at extremely preterm gestational ages are typically admitted to the neonatal intensive care unit (NICU) after initial resuscitation. The subsequent hospital course can be highly variable, and despite counseling aided by available risk calculators, there are significant challenges with shared decision-making regarding life support and transition to end-of-life care. Improving predictive models can help providers and families navigate these unique challenges.
Machine learning methods have previously demonstrated added predictive value for determining intensive care unit outcomes, and their use allows consideration of a greater number of factors that potentially influence newborn outcomes, such as maternal characteristics. Machine learning-based models were analyzed for their ability to predict the survival of extremely preterm neonates at initial admission.
Maternal and newborn information was extracted from the health records of infants born between 23 and 29 weeks of gestation in the Medical Information Mart for Intensive Care III (MIMIC-III) critical care database. Applicable machine learning models predicting survival during the initial NICU admission were developed and compared. The same type of model was also examined using only features that would be available prepartum for the purpose of survival prediction prior to an anticipated preterm birth. Features most correlated with the predicted outcome were determined when possible for each model.
Of included patients, 37 of 459 (8.1%) expired. The resulting random forest model showed higher predictive performance than the frequently used Score for Neonatal Acute Physiology With Perinatal Extension II (SNAPPE-II) NICU model when considering extremely preterm infants of very low birth weight. Several other machine learning models were found to have good performance but did not show a statistically significant difference from previously available models in this study. Feature importance varied by model, and those of greater importance included gestational age; birth weight; initial oxygenation level; elements of the APGAR (appearance, pulse, grimace, activity, and respiration) score; and amount of blood pressure support. Important prepartum features also included maternal age, steroid administration, and the presence of pregnancy complications.
Machine learning methods have the potential to provide robust prediction of survival in the context of extremely preterm births and allow for consideration of additional factors such as maternal clinical and socioeconomic information. Evaluation of larger, more diverse data sets may provide additional clarity on comparative performance.
Journal Article
Normalization of ADC does not improve correlation with overall survival in patients with high-grade glioma (HGG)
Mixed reports leave uncertainty about whether normalization of apparent diffusion coefficient (ADC) to a within-subject white matter reference is necessary for assessment of tumor cellularity. We tested whether normalization improves the previously reported correlation of resection margin ADC with 15-month overall survival (OS) in HGG patients. Spin-echo echo-planar DWI was retrieved from 3 T MRI acquired between maximal resection and radiation in 37 adults with new-onset HGG (25 glioblastoma; 12 anaplastic astrocytoma). ADC maps were produced with the FSL DTIFIT tool (Oxford Centre for Functional MRI). 3 neuroradiologists manually selected regions of interest (ROI) in normal appearing white matter (NAWM) and in non-enhancing tumor (NT) < 2 cm from the margin of residual enhancing tumor or resection cavity. Normalized ADC (nADC) was computed as the ratio of absolute NT ADC to NAWM ADC. Reproducibility of nADC and absolute ADC among the readers’ ROI was assessed using intra-class correlation coefficient (ICC) and within-subject coefficient of variation (wCV). Correlations of ADC and nADC with OS were compared using receiver operating characteristics (ROC) analysis. A p value 0.05 was considered statistically significant. Both mean ADC and nADC differed significantly between patients subgrouped by 15-month OS (p = 0.0014 and 0.0073 respectively). wCV and ICC among the readers were similar for absolute and normalized ADC. In ROC analysis of correlation with OS, nADC did not perform significantly better than absolute ADC. Normalization does not significantly improve the correlation of absolute ADC with OS in HGG, suggesting that normalization is not necessary for clinical or research ADC analysis in HGG patients.
Journal Article
EGFR Mutation Testing of non-squamous NSCLC: Impact and Uptake during Implementation of Testing Guidelines in a Population-Based Registry Cohort from Northern New Zealand
Background
Since 2013, clinical practice guidelines recommend
EGFR
mutation testing of non-squamous NSCLC to select advanced-stage patients for first-line treatment using EGFR-TKIs.
Objective
We aimed to determine population-based trends in the real-world uptake and impact in routine practice of these recently updated testing guidelines.
Patients and Methods
A population-based observational study was conducted of notifications to the New Zealand Cancer Registry of patients eligible for
EGFR
testing diagnosed in northern New Zealand between January 2010 and April 2014. The main study variable was
EGFR
mutation testing. Main outcome measures (overall survival and dispensing of EGFR-TKIs) were extracted from prospectively archived electronic databases until October 2015.
Results
The population-based cohort of 1857 patients had an average age of 70 years. Most had adenocarcinoma and metastatic disease at diagnosis.
EGFR
testing was undertaken in 500 patients (27%) with mutations detected in 109 patients (22%).
EGFR
testing increased during the period of study from <5% to 67% of patients (
P
< 0.0001). Full uptake of testing by all eligible patients was limited by a lack of availability of specimens for testing and variable testing referral practices. The proportion of patients treated with EGFR-TKIs decreased during the same time period, both among untested patients (from 12.2% to 2.8% (
P
< 0.0001)) and in the population as a whole (from 13.7% to 10.6% (
P
< 0.05)).
EGFR
testing was associated with prolonged overall survival (Adjusted HR = 0.76 (95% CI, 0.65–0.89) Log-rank
P
< 0.0001) due at least in part to the much longer overall survival achieved by mutation-positive patients, of whom 79% received EGFR-TKIs. Compared to untested EGFR-TKI-treated patients, mutation-positive EGFR-TKI-treated patients received EGFR-TKIs for longer, and survived longer both from the start of EGFR-TKI treatment and date of their diagnosis.
Conclusions
In this real world setting, high uptake of
EGFR
testing was achieved and associated with major changes in EGFR-TKI prescribing and improved health outcomes. Modifiable factors determined testing uptake.
Study registration ACTRN12615000998549.
Journal Article
China high melt index HDPE up on strong demand
China's import prices for high density polyethylene (HDPE) high MI (melt index) injection surged on the back of tight spot supply and strong demand. Supply of cargoes from India and Iran has tightened amid lockdowns implemented to contain the pandemic and this may continue until June. Industry sources said HDPE high MI injection is used in the manufacture of N95 masks, which is in high demand. It can be also used to make a composite fibre, along with polypropylene fibre, for sanitary towels, nappies and toiletries. The quantity of HDPE high MI injection used in N95 masks, however, is negligible in terms of impacting the overall market.
Trade Publication Article
Economic concerns hit China polyolefins
Pessimism prevails in the China polyolefins market amid weakening supply-demand fundamentals, after circuit breakers were triggered four times in the US stock markets in March and Brent crude tumbled to an 18-year low. The crude crash has been rippling through the world's financial markets, raising concerns about a global economic recession. The pain is being felt in the polyolefins market, albeit only slightly for now. On Mar 23, linear low density polyethylene prices in east China were assessed at yuan (CNY) 6,250-6,600/tonne, down by 1.53% from the last weekly assessment ended Mar 20, while polypropylene yarn prices were at CNY6,450-6,700/tonne, shedding 2.2%, ICIS assessments showed.
Trade Publication Article
Iran, Korea PE, PP to China to fall
Polyolefins supply to China from Iran and South Korea, which are both struggling with rising confirmed cases of coronavirus infection, may decline. China's imports of Iranian polyethylene in 2019 stood at 2.56m tonnes; while it took in 1.21m tonnes of the same material from South Korea, official data showed. For polypropylene, China took in 1.07m tonnes from South Korea, accounting for about 21% of its total imports of the material last year, according to China Customs data. Since Feb 23, Iran's neighbours, including Turkey, Pakistan, Armenia and Afghanistan, have decided to close their borders with Tehran or suspend traffic to and from the country, news agency Al Jazeera reported.
Trade Publication Article
China may re-open for US polyolefins
China's arbitrage window for US polyolefin imports may reopen on the tariffs exemptions announced by the country's state council, although its impact on the market may be felt in the long term only. Domestic firms in China that intend to purchase and import relevant listed US goods can submit an exemption application after 2 March. Once approved, China will not impose any additional tariffs against the Section 301 trade measure for a period of one year--though there are certain conditions on volume and monthly imports. High density polyethylene, linear low density PE and polypropylene homopolymers are included in the list, with all three subject to an additional 27.5% tariff. China will purchase and import from the US at least $18.5 billion in 2020 and $33.9 billion in 2021 of energy products.
Trade Publication Article
China polyolefins cut output
China's polyolefin suppliers have cut their post-holiday production due to logistics restrictions amid authorities' efforts to contain the coronavirus outbreak. Domestic inventories are high as the plants did not stop production during the Lunar New Year holiday ,with most storage now full. Some are being forced to rent warehouses as the resins could not be delivered to other provinces amid restrictions on domestic transportation and reduced manpower as the holiday was extended in various provinces.
Trade Publication Article
China plastics ban to boost demand
China's move to phase out single-use plastics over a five-year period may boost demand for virgin polyolefins in the near term, but focus will be on developing recyclable and degradable materials. New regulations to control plastic pollution were recently rolled out, banning production and sales of plastic bags that are less than 0.025mm thick, and plastic film of less than 0.01mm thick for agricultural use. Increasing the thickness of plastics bags from the wafer-thin level of 0.008-0.015mm will boost demand for virgin high density polyethylene (HDPE) film; while the same for agriculture film will lead to higher consumption of linear low density PE. China's efforts to ban the use of free ultra-thin plastic bags started in 2008, but have failed to sharply reduce product consumption as reflected by the growth in HDPE demand in recent years.
Trade Publication Article