164 results on '"Seyed Ehsan Saffari"'
Search Results
2. Long-term outcomes of subthalamic nucleus deep brain stimulation for Parkinson’s disease in Singapore
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Yi Zhan Cai, Yilong Zheng, Wei Li, Seyed Ehsan Saffari, Hwee Lan Ng, Angela Zhan, Zheyu Xu, Kay Yaw Tay, Wing Lok Au, Wai Hoe Ng, Louis Chew Seng Tan, Kai Rui Wan, and Shermyn Neo
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Medicine - Abstract
Introduction: Subthalamic nucleus deep brain stimulation (STN-DBS) is a proven treatment modality for Parkinson’s disease (PD), reducing dyskinesia and time spent in the “OFF” state. This study evaluates the long-term outcomes of STN-DBS in PD patients up to 10 years post-surgery in Singapore. Method: We conducted a retrospective review of Movement Disorders Society-Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) scores, activities of daily living (ADLs), disease milestones, dopaminergic drug prescriptions, and adverse events in patients before and after STN-DBS surgery. Results: A total of 94 PD patients who underwent bilateral STN-DBS were included. STN-DBS reduced time in the “OFF” state by 36.9% at 1 year (P=0.034) and 40.9% at 5 years (P=0.006). Time with dyskinesia did not significantly change. Levodopa equivalent daily dose was reduced by 35.1% by 5 years (P less than 0.001). MDS-UPDRS-II and III scores increased from 5 years post-DBS by 40.5% and 35.4%, respectively. Independence in ADLs decreased, though not significantly. The prevalence of frequent falls increased at 5 years. Surgery- and device-related adverse events were uncommon and generally mild. Conclusion: STN-DBS provides sustained relief from motor complications and reduced medication requirements in PD patients in Singapore. This study highlights STN-DBS as an effective treatment option, significantly enhancing the quality of life for those with PD.
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- 2024
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3. The influence of pain catastrophizing on pain and function after knee arthroplasty in knee osteoarthritis
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Diana Chan, Seyed Ehsan Saffari, Steven Bak Siew Wong, Seng Jin Yeo, Vikki Wylde, Julian Thumboo, and Ying-Ying Leung
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Knee osteoarthritis ,Knee arthroplasty ,Pain catastrophizing ,Pain ,Function ,Medicine ,Science - Abstract
Abstract Pain catastrophizing is an exaggerated focus on pain sensations. It may be an independent factor influencing pain and functional outcomes of knee arthroplasty. We aimed to evaluate the association between pre-operative pain catastrophizing with pain and function outcomes up to one year after knee arthroplasty. We used data from a cohort study of patients undergoing primary knee arthroplasty (either total or unicompartmental arthroplasty) for knee osteoarthritis. Pain catastrophizing was assessed pre-operatively using the Pain Catastrophizing scale (PCS). Other baseline variables included demographics, body mass index, radiographic severity, anxiety, depression, and knee pain and function assessed using the Western Ontario and McMaster University Index (WOMAC). Patients completed the WOMAC at 6- and 12-months after arthroplasty. WOMAC pain and function scores were converted to interval scale and the association of PCS and changes of WOMAC pain and function were evaluated in generalized linear regression models with adjustment with confounding variables. Of the 1136 patients who underwent arthroplasty (70% female, 84% Chinese, 92% total knee arthroplasty), 1102 and 1089 provided data at 6- and 12-months post-operatively. Mean (± SD) age of patients was 65.9 (± 7.0) years. PCS was associated with a change in WOMAC pain at both 6-months and 12-months (β = − 0.04, 95% confidence interval: − 0.06, − 0.02; P
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- 2024
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4. A comparison of multiple sclerosis disease characteristics across three genetically diverse Asian racial groups in Singapore
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Min Jie Koh, Seyed Ehsan Saffari, Janis Siew Noi Tye, Amelia Yun Yi Aw, Rachel Wan En Siew, Xuejuan Peng, Jeanne May May Tan, Kevin Tan, and Tianrong Yeo
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Medicine ,Science - Abstract
Abstract Studies in Western populations have shown that Black and Hispanic patients have an earlier age of Multiple Sclerosis (MS) onset and a more severe disease course characterised by faster disability accrual compared to Whites. It is yet unclear whether MS disease characteristics and clinical course differ amongst Asian racial groups. Singapore is uniquely poised to investigate this as its multi-racial population comprises three genetically diverse Asian racial groups—Chinese, Malay and South Asian. Herein, we sought to elucidate differences in the clinical phenotypes, disease-modifying therapy (DMT) usage, and disease course amongst these three Asian racial groups by performinga retrospective observational study on MS patients seen at the National Neuroscience Institute, Singapore. Data on demographics, disease characteristics, ancillary investigations, and DMT usage were collected. One hundred and eighty-eight patients were included (90 Chinese, 32 Malay, and 66 South Asian). Our findings showed that MS prevalence was the highest in South Asians followed by Malays and Chinese, while demographics, healthcare access, and longer-term disease course were identical across the racial groups. However, several differences and trends were elucidated: (1) South Asian patients had milder sentinel attacks (p = 0.006), (2) a higher proportion of Malay patients had enhancing lesions on their initial MRI (p = 0.057) and the lesion topography differed across the races (p = 0.034), and (3) more Malay patients switched out of their initial DMT (p = 0.051). In conclusion, MS disease characteristics were largely similar across these three Asian racial groups, and while there were some clinical and radiological differences at presentation, these did not influence longer-term outcomes.
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- 2024
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5. Tumour growth rate predicts overall survival in patients with recurrent WHO grade 4 glioma
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Jeffer Hann Wei Pang, Seyed Ehsan Saffari, Guan Rong Lee, Wai-Yung Yu, Choie Cheio Tchoyoson Lim, Kheng Choon Lim, Chia Ching Lee, Wee Yao Koh, Wei Tsau, David Chia, Kevin Lee Min Chua, Chee Kian Tham, Yin Yee Sharon Low, Wai Hoe Ng, Chyi Yeu David Low, and Xuling Lin
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Glioblastoma ,Magnetic resonance imaging ,Prognostic factor ,Tumour volume ,Medical technology ,R855-855.5 - Abstract
Abstract Purpose Accurate prognostication may aid in the selection of patients who will benefit from surgery at recurrent WHO grade 4 glioma. This study aimed to evaluate the role of serial tumour volumetric measurements for prognostication at first tumour recurrence. Methods We retrospectively analyzed patients with histologically-diagnosed WHO grade 4 glioma at initial and at first tumour recurrence at a tertiary hospital between May 2000 and September 2018. We performed auto-segmentation using ITK-SNAP software, followed by manual adjustment to measure serial contrast-enhanced T1W (CE-T1W) and T2W lesional volume changes on all MRI images performed between initial resection and repeat surgery. Results Thirty patients met inclusion criteria; the median overall survival using Kaplan-Meier analysis from second surgery was 10.5 months. Seventeen (56.7%) patients received treatment post second surgery. Univariate cox regression analysis showed that greater rate of increase in lesional volume on CE-T1W (HR = 2.57; 95% CI [1.18, 5.57]; p = 0.02) in the last 2 MRI scans leading up to the second surgery was associated with a higher mortality likelihood. Patients with higher Karnofsky Performance Score (KPS) (HR = 0.97; 95% CI [0.95, 0.99]; p = 0.01) and who received further treatment following second surgery (HR = 0.43; 95% CI [0.19, 0.98]; p = 0.04) were shown to have a better survival. Conclusion Higher rate of CE-T1W lesional growth on the last 2 MRI images prior to surgery at recurrence was associated with increase mortality risk. A larger prospective study is required to determine and validate the threshold to distinguish rapidly progressive tumour with poor prognosis.
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- 2024
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6. Machine Learning for Early Detection of Cognitive Decline in Parkinson’s Disease Using Multimodal Biomarker and Clinical Data
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Raziyeh Mohammadi, Samuel Y. E. Ng, Jayne Y. Tan, Adeline S. L. Ng, Xiao Deng, Xinyi Choi, Dede L. Heng, Shermyn Neo, Zheyu Xu, Kay-Yaw Tay, Wing-Lok Au, Eng-King Tan, Louis C. S. Tan, Ewout W. Steyerberg, William Greene, and Seyed Ehsan Saffari
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neurodegenerative disease ,cognitive dysfunction ,Parkinson’s disease ,early diagnosis ,risk assessment ,machine learning ,Biology (General) ,QH301-705.5 - Abstract
Background: Parkinson’s disease (PD) is the second most common neurodegenerative disease, primarily affecting the middle-aged to elderly population. Among its nonmotor symptoms, cognitive decline (CD) is a precursor to dementia and represents a critical target for early risk assessment and diagnosis. Accurate CD prediction is crucial for timely intervention and tailored management of at-risk patients. This study used machine learning (ML) techniques to predict the CD risk over five-year in early-stage PD. Methods: Data from the Early Parkinson’s Disease Longitudinal Singapore (2014 to 2018) was used to predict CD defined as a one-unit annual decrease or a one-unit decline in Montreal Cognitive Assessment over two consecutive years. Four ML methods—AutoScore, Random Forest, K-Nearest Neighbors and Neural Network—were applied using baseline demographics, clinical assessments and blood biomarkers. Results: Variable selection identified key predictors of CD, including education year, diastolic lying blood pressure, diastolic standing blood pressure, systolic lying blood pressure, Hoehn and Yahr scale, body mass index, phosphorylated tau at threonine 181, total tau, Neurofilament light chain and suppression of tumorigenicity 2. Random Forest was the most effective, achieving an AUC of 0.93 (95% CI: 0.89, 0.97), using 10-fold cross-validation. Conclusions: Here, we demonstrate that ML-based models can identify early-stage PD patients at high risk for CD, supporting targeted interventions and improved PD management.
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- 2024
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7. Normative data for baseline and longitudinal neuropsychological assessments in Singapore
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Wilbur Zhi Hao Koh, See Ann Soo, Seyed Ehsan Saffari, Hui Jin Chiew, Adeline Su Lyn Ng, Kok Pin Ng, and Nagaendran Kandiah
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Medicine - Abstract
Neuropsychological assessments play a vital role in the early detection of cognitive disorders. However, the lack of Singapore-specific norms has resulted in a reliance on international, usually Western, norms that potentially reduce the accuracy and reliability of assessments due to sociocultural differences.1 Moreover, the lack of longitudinal norms limits the reliable monitoring of cognitive changes over time.
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- 2024
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8. BNT162b2 vaccine induced variant-specific immunity, safety and risk of Omicron breakthrough infection in children aged 5 to 11 years: a cohort study
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Chee Fu Yung, Nina Le Bert, Kai Qian Kam, Seyed Ehsan Saffari, Chee Wah Tan, Yun Yan Mah, Jinyan Zhang, Aileen Ying-Yan Yeoh, Feng Zhu, Smrithi Hariharaputran, Chia Yin Chong, Antonio Bertoletti, and Linfa Wang
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Medicine ,Science - Abstract
Abstract There is little information on BNT162b2 vaccine-induced variant-specific immunogenicity, safety data and dynamics of breakthrough infections in pediatric populations. We addressed these questions using a prospective two dose BNT162b2 (10 mcg) vaccination cohort study of healthy children 5–11 years in Singapore. Follow up included blood samples at scheduled visits, daily vaccination symptom diary and confirmation of SARS-CoV-2 infection. Surrogate virus neutralization test (sVNT) and spike-specific T cell responses against SARS-CoV-2 variants were performed. The mean age of 127 participants was 8.27 years (SD 1.95) and 51.2% were males. The median sVNT level against original variant after 1 dose and 2 dose vaccination was 61.4% and 95.1% respectively (p
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- 2023
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9. Non-Hypertensives and Those with Normal Cholesterol Are More Likely to Have Concomitant Cancer amongst Patients with Ischemic Stroke: A Retrospective Cross-Sectional Registry-Based Study
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Kendra Jing Ying Tang, Seyed Ehsan Saffari, Kaavya Narasimhalu, Kian Kheng Queck, and Deidre Anne De Silva
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ischemic stroke ,cancer ,occult malignancy ,registries ,risk factors ,incidence ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Introduction: Patients with cancer are known to have an increased risk of ischemic stroke (IS) around the time of their diagnosis. However, there is a paucity of data in Asian populations, and as such, we aimed to determine cancer incidence rates and patterns in Asian IS patients as well as investigate the differences in vascular risk profile of IS patients with and without concomitant cancer. Methods: We conducted a retrospective cross-sectional study using data from the Singapore Stroke and Cancer registries. We defined cases as patients with IS and a cancer diagnosis 2 years before or after the index IS. Cancer incidence was determined using the same direct age-standardization method performed for the Singapore general population in the 2015 Singapore cancer report. Multivariable logistic regression was used to analyze differences in vascular risk factors. Results: Among 21,068 IS patients (mean age, 67.9 ± 13.3 years), 6.3% (1,330) were found to have concomitant cancer; 4.4% (935) had prior cancer while 1.8% (395) had cancer diagnoses within 2 years following IS. The cancer incidence among IS patients was 3,393 (95% confidence interval [CI], 1,937–4,849) per 100,000 person-years compared to 219–231 per 100,000 person-years in the general population. Older age (odds ratio [OR], 1.02 [95% CI, 1.01–1.02] per year), males (OR, 1.25 [95% CI, 1.11–1.41), Chinese ethnicity (OR, 1.61 [95% CI, 1.37–1.89]) and a lower prevalence of hypertension (OR, 0.84 [95% CI, 0.73–0.97)]), and hyperlipidemia (OR, 0.53 [95% CI, 0.45–0.62]) were independently associated with cancer-related IS. Conclusions: The age-standardized cancer incidence was 15 times higher in IS patients than the general population. IS patients with concomitant cancer were older and had a lower prevalence of vascular risk factors.
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- 2023
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10. AutoScore-Ordinal: an interpretable machine learning framework for generating scoring models for ordinal outcomes
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Seyed Ehsan Saffari, Yilin Ning, Feng Xie, Bibhas Chakraborty, Victor Volovici, Roger Vaughan, Marcus Eng Hock Ong, and Nan Liu
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Interpretable machine learning ,Medical decision making ,Clinical score ,Ordinal outcome ,Electronic health records ,Medicine (General) ,R5-920 - Abstract
Abstract Background Risk prediction models are useful tools in clinical decision-making which help with risk stratification and resource allocations and may lead to a better health care for patients. AutoScore is a machine learning–based automatic clinical score generator for binary outcomes. This study aims to expand the AutoScore framework to provide a tool for interpretable risk prediction for ordinal outcomes. Methods The AutoScore-Ordinal framework is generated using the same 6 modules of the original AutoScore algorithm including variable ranking, variable transformation, score derivation (from proportional odds models), model selection, score fine-tuning, and model evaluation. To illustrate the AutoScore-Ordinal performance, the method was conducted on electronic health records data from the emergency department at Singapore General Hospital over 2008 to 2017. The model was trained on 70% of the data, validated on 10% and tested on the remaining 20%. Results This study included 445,989 inpatient cases, where the distribution of the ordinal outcome was 80.7% alive without 30-day readmission, 12.5% alive with 30-day readmission, and 6.8% died inpatient or by day 30 post discharge. Two point-based risk prediction models were developed using two sets of 8 predictor variables identified by the flexible variable selection procedure. The two models indicated reasonably good performance measured by mean area under the receiver operating characteristic curve (0.758 and 0.793) and generalized c-index (0.737 and 0.760), which were comparable to alternative models. Conclusion AutoScore-Ordinal provides an automated and easy-to-use framework for development and validation of risk prediction models for ordinal outcomes, which can systematically identify potential predictors from high-dimensional data.
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- 2022
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11. Modelling the Distribution of Cognitive Outcomes for Early-Stage Neurocognitive Disorders: A Model Comparison Approach
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Seyed Ehsan Saffari, See Ann Soo, Raziyeh Mohammadi, Kok Pin Ng, William Greene, and Negaenderan Kandiah
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cognitive impairment ,cognitive screening tool ,Montreal Cognitive Assessment ,visual cognitive assessment test ,skewness ,Biology (General) ,QH301-705.5 - Abstract
Background: Cognitive assessments for patients with neurocognitive disorders are mostly measured by the Montreal Cognitive Assessment (MoCA) and Visual Cognitive Assessment Test (VCAT) as screening tools. These cognitive scores are usually left-skewed and the results of the association analysis might not be robust. This study aims to study the distribution of the cognitive outcomes and to discuss potential solutions. Materials and Methods: In this retrospective cohort study of individuals with subjective cognitive decline or mild cognitive impairment, the inverse-transformed cognitive outcomes are modelled using different statistical distributions. The robustness of the proposed models are checked under different scenarios: with intercept-only, models with covariates, and with and without bootstrapping. Results: The main results were based on the VCAT score and validated via the MoCA score. The findings suggested that the inverse transformation method improved the modelling the cognitive scores compared to the conventional methods using the original cognitive scores. The association of the baseline characteristics (age, gender, and years of education) and the cognitive outcomes were reported as estimates and 95% confidence intervals. Bootstrap methods improved the estimate precision and the bootstrapped standard errors of the estimates were more robust. Cognitive outcomes were widely analysed using linear regression models with the default normal distribution as a conventional method. We compared the results of our suggested models with the normal distribution under various scenarios. Goodness-of-fit measurements were compared between the proposed models and conventional methods. Conclusions: The findings support the use of the inverse transformation method to model the cognitive outcomes instead of the original cognitive scores for early-stage neurocognitive disorders where the cognitive outcomes are left-skewed.
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- 2024
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12. Biomarker characterization of clinical subtypes of Parkinson Disease
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Xiao Deng, Seyed Ehsan Saffari, Nan Liu, Bin Xiao, John Carson Allen, Samuel Yong Ern Ng, Nicole Chia, Yi Jayne Tan, Xinyi Choi, Dede Liana Heng, Yew-long Lo, Zheyu Xu, Kay-Yaw Tay, Wing-Lok Au, Adeline Ng, Eng-King Tan, and Louis C. S. Tan
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Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract The biological underpinnings of the PD clusters remain unknown as the existing PD clusters lacks biomarker characterization. We try to identify clinical subtypes of Parkinson Disease (PD) in an Asian cohort and characterize them by comparing clinical assessments, genetic status and blood biochemical markers. A total of 206 PD patients were included from a multi-centre Asian cohort. Hierarchical clustering was performed to generate PD subtypes. Clinical and biological characterization of the subtypes were performed by comparing clinical assessments, allelic distributions of Asian related PD gene (SNCA, LRRK2, Park16, ITPKB, SV2C) and blood biochemical markers. Hierarchical clustering method identified three clusters: cluster A (severe subtype in motor, non-motor and cognitive domains), cluster B (intermediate subtype with cognitive impairment and mild non-motor symptoms) and cluster C (mild subtype and young age of onset). The three clusters had significantly different allele frequencies in two SNPs (Park16 rs6679073 A allele carriers in cluster A B C: 67%, 74%, 89%, p = 0.015; SV2C rs246814 T allele distribution: 7%, 12%, 25%, p = 0.026). Serum homocysteine (Hcy) and C-reactive protein (CRP) levels were also significantly different among three clusters (Mean levels of Hcy and CRP among cluster A B C were: 19.4 ± 4.2, 18.4 ± 5.7, 15.6 ± 5.6, adjusted p = 0.005; 2.5 ± 5.0, 1.5 ± 2.4, 0.9 ± 2.1, adjusted p
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- 2022
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13. A universal AutoScore framework to develop interpretable scoring systems for predicting common types of clinical outcomes
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Feng Xie, Yilin Ning, Mingxuan Liu, Siqi Li, Seyed Ehsan Saffari, Han Yuan, Victor Volovici, Daniel Shu Wei Ting, Benjamin Alan Goldstein, Marcus Eng Hock Ong, Roger Vaughan, Bibhas Chakraborty, and Nan Liu
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Health Sciences ,Computer sciences ,Science (General) ,Q1-390 - Abstract
Summary: The AutoScore framework can automatically generate data-driven clinical scores in various clinical applications. Here, we present a protocol for developing clinical scoring systems for binary, survival, and ordinal outcomes using the open-source AutoScore package. We describe steps for package installation, detailed data processing and checking, and variable ranking. We then explain how to iterate through steps for variable selection, score generation, fine-tuning, and evaluation to generate understandable and explainable scoring systems using data-driven evidence and clinical knowledge.For complete details on the use and execution of this protocol, please refer to Xie et al. (2020),1 Xie et al. (2022)2, Saffari et al. (2022)3 and the online tutorial https://nliulab.github.io/AutoScore/. : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.
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- 2023
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14. Watchful waiting versus pharmacological management of small-for-gestational-age infants with hyperinsulinemic hypoglycemia
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Suresh Chandran, Sandra Lynn Jaya-Bodestyne, Victor Samuel Rajadurai, Seyed Ehsan Saffari, Mei Chien Chua, and Fabian Yap
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diazoxide ,hyperinsulinemic hypoglycemia ,fasting study ,small-for-gestational-age ,watchful waiting ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
IntroductionGiven that reports on severe diazoxide (DZX) toxicity are increasing, we aimed to understand if the short-term clinical outcomes of small-for-gestational-age (SGA) infants with hyperinsulinemic hypoglycemia (HH) managed primarily by supportive care, termed watchful waiting (WW), are different from those treated with DZX.MethodA real-life observational cohort study was conducted from 1 September 2014 to 30 September 2020. The WW or DZX management decision was based on clinical and biochemical criteria. We compared central line duration (CLD), postnatal length of stay (LOS), and total intervention days (TIDs) among SGA-HH infants treated with DZX versus those on a WW approach. Fasting studies determined the resolution of HH.ResultAmong 71,836 live births, 11,493 were SGA, and 51 SGA infants had HH. There were 26 and 25 SGA-HH infants in the DZX and WW groups, respectively. Clinical and biochemical parameters were similar between groups. The median day of DZX initiation was day 10 of life (range 4–32), at a median dose of 4 mg/kg/day (range 3–10). All infants underwent fasting studies. Median CLD [DZX, 15 days (6–27) vs. WW, 14 days (5–31), P = 0.582] and postnatal LOS [DZX, 23 days (11–49) vs. WW, 22 days (8–61), P = 0.915] were comparable. Median TID was >3-fold longer in the DZX than the WW group [62.5 days (9–198) vs. 16 days (6–27), P < 0.001].ConclusionCLD and LOS are comparable between WW and DZX groups. Since fasting studies determine the resolution of HH, physicians should be aware that clinical intervention of DZX-treated SGA-HH patients extends beyond the initial LOS.
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- 2023
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15. Corrigendum: Topology of diffusion changes in corpus callosum in Alzheimer's disease: An exploratory case-control study
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Sumeet Kumar, Alberto De Luca, Alexander Leemans, Seyed Ehsan Saffari, Septian Hartono, Fatin Zahra Zailan, Kok Pin Ng, and Nagaendran Kandiah
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Alzheimer's disease ,diffusion tensor imaging ,white matter tract integrity ,corpus callosum ,magnetic resonance imaging (MRI) ,diffusion kurtosis imaging ,Neurology. Diseases of the nervous system ,RC346-429 - Published
- 2023
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16. A cross-sectional study of knowledge and practices in the management of patients with Parkinson’s disease amongst public practice-based general practitioners and geriatricians
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Isis Claire Z. Y. Lim, Seyed Ehsan Saffari, and Shermyn Neo
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Parkinson’s disease ,General practitioner ,Geriatrician ,Quality measures ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background As most patients are likely to first interface with their community general practitioner (GP) or geriatrician for chronic healthcare conditions, these non-neurologists practitioners are well-placed to diagnose, initiate treatment in symptomatic Parkinson’s disease (PD) patients, and provide regular and timely management of their PD. However, current studies suggest that the role of the GP and geriatrician in providing holistic care for PD patients may be limited by factors such as patient perceptions, and a lack of knowledge base in the quality measures of care. This paper aims to better understand the different management styles between GPs and geriatricians practicing in public institutions in Singapore, qualify the difficulties they face in providing patient-centric care for PD patients, and identify any gaps in quality measures of care. Methods A questionnaire was completed anonymously by GPs (n = 43) and geriatricians (n = 33) based at public institutions, on a voluntary basis before a compulsory didactic teaching on PD. Questions were modelled after quality measures set out by the American Academy of Neurology, specifically eliciting information on falls, non-motor symptoms, exercise regime and medication-related symptoms. “PD management practices and styles” questions were answered by the respondents on a 4-point Likert scale. Results Geriatricians spent more time in consult with PD patients compared with GPs (median [Q1-Q3] = 20 [15–30] vs 10 [10–15] minutes, p
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- 2022
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17. Dementia in Southeast Asia: influence of onset-type, education, and cerebrovascular disease
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Ashwati Vipin, Vaynii Satish, Seyed Ehsan Saffari, Wilbur Koh, Levinia Lim, Eveline Silva, Mei Mei Nyu, Tanya-Marie Choong, Esther Chua, Linda Lim, Adeline Su Lyn Ng, Hui Jin Chiew, Kok Pin Ng, and Nagaendran Kandiah
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Longitudinal ,Clinical ,Alzheimer’s disease ,Cognition ,Education ,Cerebrovascular disease ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Background Southeast Asia represents 10% of the global population, yet little is known about regional clinical characteristics of dementia and risk factors for dementia progression. This study aims to describe the clinico-demographic profiles of dementia in Southeast Asia and investigate the association of onset-type, education, and cerebrovascular disease (CVD) on dementia progression in a real-world clinic setting. Methods In this longitudinal study, participants were consecutive series of 1606 patients with dementia from 2010 to 2019 from a tertiary memory clinic from Singapore. The frequency of dementia subtypes stratified into young-onset (YOD;
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- 2021
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18. Predicting atrial fibrillation after ischemic stroke: clinical, genetics and electrocardiogram modelling
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Mervyn Qi Wei Poh, Carol Huilian Tham, Jeremiah David Ming Siang Chee, Seyed Ehsan Saffari, Kenny Wee Kian Tan, Li Wei Tan, Ebonne Yulin Ng, Celestia Pei Xuan Yeo, Christopher Ying Hao Seet, Joanne Peiting Xie, Jonathan Yexian Lai, Rajinder Singh, Eng-King Tan, and Tian Ming Tu
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Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Introduction: Detection of atrial fibrillation (AF) is challenging in patients after ischemic stroke due to its paroxysmal nature. We aim to determine the utility of a combined clinical, electrocardiographic and genetic variables model to predict AF in a post-stroke population. Materials and Methods: We performed a cohort study at a single comprehensive stroke centre from 09/11/2009 to 31/10/2017. All patients recruited were diagnosed with acute ischemic stroke or transient ischemic attacks. Electrocardiographic variables including p-wave terminal force (PWTF), corrected QT interval (QTc) and genetic variables including single nucleotide polymorphisms (SNP) at the 4q25 (rs2200733) were evaluated. Clinical, electrocardiographic and genetic variables of patients without AF and those who developed AF were compared. Multiple logistic regression analysis and receiver operating characteristics were performed to identify parameters and determine their ability to predict the occurrence of AF. Results: Out of 709 patients (median age of 59 years, IQR 52-67) recruited, sixty (8.5%) were found to develop AF on follow-up. Age (odds ratio (OR): 3.49, 95% confidence interval (CI): 2.03-5.98, p
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- 2022
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19. Topology of diffusion changes in corpus callosum in Alzheimer's disease: An exploratory case-control study
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Sumeet Kumar, Alberto De Luca, Alexander Leemans, Seyed Ehsan Saffari, Septian Hartono, Fatin Zahra Zailan, Kok Pin Ng, and Nagaendran Kandiah
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Alzheimer's disease ,diffusion tensor imaging ,white matter tract integrity ,corpus callosum ,magnetic resonance imaging (MRI) ,diffusion kurtosis imaging ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
AimThis study aims to assess the integrity of white matter in various segments of the corpus callosum in Alzheimer's disease (AD) by using metrics derived from diffusion tensor imaging (DTI), diffusion kurtosis imaging (DKI) and white matter tract integrity model (WMTI) and compare these findings to healthy controls (HC).MethodsThe study was approved by the institutional ethics board. 12 AD patients and 12 HC formed the study population. All AD patients were recruited from a tertiary neurology memory clinic. A standardized battery of neuropsychological assessments was administered to the study participants by a trained rater. MRI scans were performed with a Philips Ingenia 3.0T scanner equipped with a 32-channel head coil. The protocol included a T1-weighted sequence, FLAIR and a dMRI acquisition. The dMRI scan included a total of 71 volumes, 8 at b = 0 s/mm2, 15 at b = 1,000 s/mm2 and 48 at b = 2,000 s/mm2. Diffusion data fit was performed using DKI REKINDLE and WMTI models.Results and discussionWe detected changes suggesting demyelination and axonal degeneration throughout the corpus callosum of patients with AD, most prominent in the mid-anterior and mid-posterior segments of CC. Axial kurtosis was the most significantly altered metric, being reduced in AD patients in almost all segments of corpus callosum. Reduced axial kurtosis in the CC segments correlated with poor cognition scores in AD patients in the visuospatial, language and attention domains.
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- 2022
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20. Poor sleep quality is associated with fatigue and depression in early Parkinson's disease: A longitudinal study in the PALS cohort
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Matthew Rui En Koh, Cong Yang Chua, Samuel Yong-Ern Ng, Nicole Shuang-Yu Chia, Seyed Ehsan Saffari, Regina Yu-Ying Chen, Xinyi Choi, Dede Liana Heng, Shermyn Xiumin Neo, Kay Yaw Tay, Wing Lok Au, Eng-King Tan, Louis Chew-Seng Tan, and Zheyu Xu
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Parkinson's disease ,sleep ,fatigue ,depression ,non-motor symptoms ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
BackgroundSleep disorders are common in Parkinson's disease (PD). However, the longitudinal relationship between sleep quality and the other non-motor symptoms of PD has not been well characterized, especially in early PD.ObjectiveTo explore the value of baseline sleep quality in predicting the progression of other non-motor symptoms in early PD.Methods109 early PD patients were recruited to the study. Patients were stratified into good and poor sleepers using the Pittsburgh Sleep Quality Index (PSQI). Assessments performed at baseline and 1 year follow-up included the Epworth Sleepiness Scale, Fatigue Severity Scale, Non-Motor Symptom Scale, Geriatric Depression Scale, Hospital Anxiety and Depression Scale, Apathy Scale, Montreal Cognitive Assessment and detailed neuropsychological assessments. Multivariable linear regression was performed at baseline to investigate differences in clinical scores between poor and good sleepers, while multivariable regression models were used to investigate associations between sleep quality and progression of test scores at 1 year follow-up.Results59 poor sleepers and 50 good sleepers were identified. At baseline, poor sleepers had greater HADS anxiety scores (p = 0.013) [2.99 (95% CI 2.26, 3.73)] than good sleepers [1.59 (95% CI 0.75, 2.42)]. After 1 year, poor sleepers had greater fatigue (FSS scores +3.60 as compared to −2.93 in good sleepers, p = 0.007) and depression (GDS scores +0.42 as compared to −0.70, p = 0.006).ConclusionThis study shows a longitudinal association between sleep quality, fatigue, and depression in early PD patients, independent of medication effect and disease severity, this may support the hypothesis that a common serotonergic pathway is implicated in these non-motor symptoms.
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- 2022
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21. Hemisensory syndrome: Hyperacute symptom onset and age differentiates ischemic stroke from other aetiologies
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Pei Xuan Koh, Joanna Ti, Seyed Ehsan Saffari, Zhen Yu Isis Claire Lim, and Tianming Tu
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Hemisensory syndrome ,Ischemic stroke ,Numbness ,Magnetic resonance imaging ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Background An important cause of hemisensory syndrome is ischemic stroke. However, the diagnostic yield of neuroradiological imaging on hemisensory syndrome is low. Therefore, we aim to describe patients hospitalized with isolated hemisensory syndrome, and to identify clinical features associated with an aetiology of ischemic stroke. Methods We performed a single centre retrospective observation study, identifying patients who were hospitalised with hemisensory syndrome from October 2015 to March 2016, and whom underwent a magnetic resonance imaging (MRI) brain during the admission. Ischemic stroke was defined as the presence of restricted diffusion-weighted image on the MRI brain. Clinical information was analysed and compared between patients with and without stroke seen on MRI brain. Results 79 patients, 36 (45.6%) males and 43 (54.4%) females, aged between 30 to 87 years (mean 54), were included in the final analysis. 18 (22.8%) patients were identified to have an acute ischemic stroke. Clinical features associated with ischemic stroke in hospitalised patients with hemisensory syndrome include symptom onset of ≤24 h at presentation (odds ratio 31.4, 95% CI 3.89–254.4), advanced age (odds ratio 1.14, CI 1.05–1.25) and smoking (odds ratio 7.35, 95% CI 1.20–45). Conclusion Older patients, with a history of smoking, and who present with an acute onset of symptoms, are more likely to have ischemic stroke as the cause of their hemisensory syndrome.
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- 2021
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22. Treatment of Primary Aldosteronism and Reversal of Renin Suppression Improves Left Ventricular Systolic Function
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Troy H. Puar, Chin Kai Cheong, Roger S.Y. Foo, Seyed Ehsan Saffari, Tian Ming Tu, Min Ru Chee, Meifen Zhang, Keng Sin Ng, Kang Min Wong, Andrew Wong, Foo Cheong Ng, Tar Choon Aw, Joan Khoo, Linsey Gani, Thomas King, Wann Jia Loh, Shui Boon Soh, Vanessa Au, Tunn Lin Tay, Eberta Tan, Lily Mae, Jielin Yew, Yen Kheng Tan, Khim Leng Tong, Sheldon Lee, and Siang Chew Chai
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hyperaldosteronism ,adrenalectomy ,secondary hypertension ,adrenal vein sampling (AVS) ,myocardial strain analysis ,ejection fraction (EF) ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
IntroductionPrimary aldosteronism (PA) is associated with increased risk of cardiovascular events. However, treatment of PA has not been shown to improve left ventricular (LV) systolic function using the conventional assessment with LV ejection fraction (LVEF). We aim to use speckle-tracking echocardiography to assess for improvement in subclinical systolic function after treatment of PA.MethodsWe prospectively recruited 57 patients with PA, who underwent 24-h ambulatory blood pressure (BP) measurements and echocardiography, including global longitudinal strain (GLS) assessment of left ventricle, at baseline and 12 months post-treatment.ResultsAt baseline, GLS was low in 14 of 50 (28.0%) patients. On multivariable analysis, GLS was associated with diastolic BP (P = 0.038) and glomerular filtration rate (P = 0.026). GLS improved post-surgery by −2.3, 95% CI: −3.9 to −0.6, P = 0.010, and post-medications by −1.3, 95% CI: −2.6 to 0.03, P = 0.089, whereas there were no changes in LVEF in either group. Improvement in GLS was independently correlated with baseline GLS (P < 0.001) and increase in plasma renin activity (P = 0.007). Patients with post-treatment plasma renin activity ≥1 ng/ml/h had improvements in GLS (P = 0.0019), whereas patients with persistently suppressed renin had no improvement. Post-adrenalectomy, there were also improvements in LV mass index (P = 0.012), left atrial volume index (P = 0.002), and mitral E/e’ (P = 0.006), whereas it was not statistically significant in patients treated with medications.ConclusionTreatment of hyperaldosteronism is effective in improving subclinical LV systolic dysfunction. Elevation of renin levels after treatment, which reflects adequate reversal of sodium overload state, is associated with better systolic function after treatment.Clinical Trial Registrationwww.ClinicalTrials.gov, identifier: NCT03174847.
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- 2022
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23. Development and validation of an interpretable prehospital return of spontaneous circulation (P-ROSC) score for patients with out-of-hospital cardiac arrest using machine learning: A retrospective study
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Nan Liu, Mingxuan Liu, Xinru Chen, Yilin Ning, Jin Wee Lee, Fahad Javaid Siddiqui, Seyed Ehsan Saffari, Andrew Fu Wah Ho, Sang Do Shin, Matthew Huei-Ming Ma, Hideharu Tanaka, and Marcus Eng Hock Ong
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Out-of-hospital cardiac arrest ,Return of spontaneous circulation ,Interpretable machine learning ,Score ,Medicine (General) ,R5-920 - Abstract
Summary: Background: Return of spontaneous circulation (ROSC) before arrival at the emergency department is an early indicator of successful resuscitation in out-of-hospital cardiac arrest (OHCA). Several ROSC prediction scores have been developed with European cohorts, with unclear applicability in Asian settings. We aimed to develop an interpretable prehospital ROSC (P-ROSC) score for ROSC prediction based on patients with OHCA in Asia. Methods: This retrospective study examined patients who suffered from OHCA between Jan 1, 2009 and Jun 17, 2018 using data recorded in the Pan-Asian Resuscitation Outcomes Study (PAROS) registry. AutoScore, an interpretable machine learning framework, was used to develop P-ROSC. On the same cohort, the P-ROSC was compared with two clinical scores, the RACA and the UB-ROSC. The predictive power was evaluated using the area under the curve (AUC) in the receiver operating characteristic analysis. Findings: 170,678 cases were included, of which 14,104 (8.26%) attained prehospital ROSC. The P-ROSC score identified a new variable, prehospital drug administration, which was not included in the RACA score or the UB-ROSC score. Using only five variables, the P-ROSC score achieved an AUC of 0.806 (95% confidence interval [CI] 0.799–0.814), outperforming both RACA and UB-ROSC with AUCs of 0.773 (95% CI 0.765–0.782) and 0.728 (95% CI 0.718–0.738), respectively. Interpretation: The P-ROSC score is a practical and easily interpreted tool for predicting the probability of prehospital ROSC. Funding: This research received funding from SingHealth Duke-NUS ACP Programme Funding (15/FY2020/P2/06-A79).
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- 2022
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24. Intracranial Pressure as an Objective Biomarker of Decompression Adequacy in Large Territory Infarction: A Multicenter Observational Study
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Jia Xu Lim, Sherry Jiani Liu, Tien Meng Cheong, Seyed Ehsan Saffari, Julian Xinguang Han, and Min Wei Chen
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large territory infarctions ,decompressive craniectomy ,intracranial pressure ,modified Rankin scale ,outcomes ,middle cerebral artery infarction ,Surgery ,RD1-811 - Abstract
BackgroundDecompressive craniectomy (DC) improves the survival and functional outcomes in patients with malignant cerebral infarction. Currently, there are no objective intraoperative markers that indicates adequate decompression. We hypothesise that closure intracranial pressure (ICP) correlates with postoperative outcomes.MethodsThis is a multicentre retrospective review of all 75 DCs performed for malignant cerebral infarction. The patients were divided into inadequate ICP (iICP) and good ICP (gICP) groups based on a suitable ICP threshold determined with tiered receiver operating characteristic and association analysis. Multivariable logistic regression was performed for various postoperative outcomes.ResultsAn ICP threshold of 7 mmHg was determined, with 36 patients (48.0%) and 39 patients (52.0%) in the iICP and gICP group, respectively. After adjustment, postoperative osmotherapy usage was more likely in the iICP group (OR 6.32, p = 0.003), and when given, was given for a longer median duration (iICP, 4 days; gICP, 1 day, p = 0.003). There was no difference in complications amongst both groups. When an ICP threshold of 11 mmHg was applied, there was significant difference in the duration on ventilator (ICP ≥11 mmHg, 3–9 days, ICP
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- 2022
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25. External validation of stroke mimic prediction scales in the emergency department
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Tian Ming Tu, Guan Zhong Tan, Seyed Ehsan Saffari, Chee Keong Wee, David Jeremiah Ming Siang Chee, Camlyn Tan, and Hoon Chin Lim
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Thrombolytic therapy ,Clinical decision-making ,Predictive value of tests ,Humans ,Adults ,Stroke/etiology ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Background Acute ischemic stroke is a time-sensitive emergency where accurate diagnosis is required promptly. Due to time pressures, stroke mimics who present with similar signs and symptoms as acute ischemic stroke, pose a diagnostic challenge to the emergency physician. With limited access to investigative tools, clinical prediction, tools based only on clinical features, may be useful to identify stroke mimics. We aim to externally validate the performance of 4 stroke mimic prediction scales, and derive a novel decision tree, to improve identification of stroke mimics. Methods We performed a retrospective cross-sectional study at a primary stroke centre, served by a telestroke hub. We included consecutive patients who were administered intravenous thrombolysis for suspected acute ischemic stroke from January 2015 to October 2017. Four stroke mimic prediction tools (FABS, simplified FABS, Telestroke Mimic Score and Khan Score) were rated simultaneously, using only clinical information prior to administration of thrombolysis. The final diagnosis was ascertained by an independent stroke neurologist. Area under receiver operating curve (AUROC) analysis was performed. A classification tree analysis was also conducted using variables which were found to be significant in the univariate analysis. Results Telestroke Mimic Score had the highest discrimination for stroke mimics among the 4 scores tested (AUROC = 0.75, 95% CI = 0.63–0.87). However, all 4 scores performed similarly (DeLong p > 0.05). Telestroke Mimic Score had the highest sensitivity (91.3%), while Khan score had the highest specificity (88.2%). All 4 scores had high positive predictive value (88.1 to 97.5%) and low negative predictive values (4.7 to 32.3%). A novel decision tree, using only age, presence of migraine and psychiatric history, had a higher prediction performance (AUROC = 0.80). Conclusion Four tested stroke mimic prediction scales performed similarly to identify stroke mimics in the emergency setting. A novel decision tree may improve the identification of stroke mimics.
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- 2020
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26. Utility of plasma Neurofilament light as a diagnostic and prognostic biomarker of the postural instability gait disorder motor subtype in early Parkinson’s disease
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Adeline Su Lyn Ng, Yi Jayne Tan, Alisa Cui Wen Yong, Seyed Ehsan Saffari, Zhonghao Lu, Ebonne Yulin Ng, Samuel Yong Ern Ng, Nicole Shuang Yu Chia, Xinyi Choi, Dede Heng, Shermyn Neo, Zheyu Xu, Nicole Chwee Har Keong, Kay Yaw Tay, Wing Lok Au, Louis Chew Seng Tan, and Eng-King Tan
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Parkinson’s disease ,Motor subtype ,PIGD ,Biomarkers ,Neurofilament light chain ,Cognition ,Neurology. Diseases of the nervous system ,RC346-429 ,Geriatrics ,RC952-954.6 - Abstract
Abstract Background The main motor subtypes of Parkinson’s disease (PD) include tremor-dominant (TD) and postural instability gait disorder (PIGD), with varying disease course that warrant the development of biomarkers capable of predicting progression according to motor subtype. The PIGD subtype is associated with a poorer prognosis, hence identification of a biomarker associated with PIGD is clinically relevant. Neurofilament light (NfL) chain is a potential biomarker of disease severity in neurological disorders including PD. However, no study has investigated NfL and PD motor subtypes. Here, we aimed to investigate the diagnostic and prognostic utility of plasma NfL for PD motor subtypes in early Parkinson’s disease. Given the higher risk for cognitive and motor decline in PIGD, we hypothesized that plasma NfL is a potential biomarker for PIGD. Methods Plasma NfL was measured in 199 participants (149 PD and 50 healthy controls, HC) using an ultrasensitive single molecule array. Patients were classified into TD or PIGD based on MDS-UPDRS components. After 2 years, 115 patients were reassessed. Association between NfL and clinical measures in PIGD and TD at baseline and at 2-year follow-up were analysed. Results At baseline, plasma NfL levels were higher in PD than HC (8.8 ± 3.4 vs 16.2 ± 7.6 pg/ml, p
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- 2020
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27. Primary Aldosteronism More Prevalent in Patients With Cardioembolic Stroke and Atrial Fibrillation
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Van Nguyen, Tian Ming Tu, Marlie Jane B. Mamauag, Jovan Lai, Seyed Ehsan Saffari, Tar Choon Aw, Lizhen Ong, Roger S. Y. Foo, Siang Chew Chai, Shaun Fones, Meifen Zhang, and Troy H. Puar
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hyperaldosteronism ,cerebrovascular accident ,transient ischaemic attack ,atrial fibrillation ,secondary hypertension ,endocrine hypertension ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
BackgroundPrimary aldosteronism (PA) is the most common cause of secondary hypertension, and patients are at an increased risk of atrial fibrillation (AF) and stroke. We assessed the prevalence of PA in patients with recent stroke.MethodsWe recruited 300 patients admitted to an acute stroke unit with diagnosis of cerebrovascular accident (haemorrhagic/ischaemic) or transient ischaemic attack. Three months post-stroke, plasma renin and aldosterone were measured. Patients with an elevated aldosterone–renin ratio proceeded to the confirmatory saline loading test.ResultsTwenty-six of 192 (14%) patients had an elevated aldosterone–renin ratio. Three of 14 patients who proceeded to saline loading were confirmed with PA (post-saline aldosterone >138 pmol/l). Another three patients were classified as confirmed/likely PA based on the markedly elevated aldosterone–renin ratio and clinical characteristics. The overall prevalence of PA amongst stroke patients with hypertension was 4.0% (95% confidence interval (CI): 0.9%–7.1%). Prevalence of PA was higher amongst patients with cardioembolic stroke, 11% (95% CI: 1.3%–33%), resistant hypertension, 11% (95% CI: 0.3%–48%), and hypertension and AF, 30% (95%CI: 6.7%–65%). If only young patients or those with hypokalaemia were screened for PA, half of our patients with PA would not have been diagnosed. Our decision tree identified that stroke patients with AF and diastolic blood pressure ≥83mmHg were most likely to have PA.ConclusionWe found that amongst hypertensive patients with stroke, PA was more prevalent in those with AF, or cardioembolic stroke. Screening for PA should be considered for all patients with stroke.
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- 2022
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28. Gender disparities among adult recipients of layperson bystander cardiopulmonary resuscitation by location of cardiac arrest in Pan-Asian communities: A registry-based study
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Nan Liu, Yilin Ning, Marcus Eng Hock Ong, Seyed Ehsan Saffari, Hyun Ho Ryu, Kentaro Kajino, Chih-Hao Lin, Sarah Abdul Karim, G.V. Ramana Rao, Andrew Fu Wah Ho, Shir Lynn Lim, and Fahad Javaid Siddiqui
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Out-of-hospital cardiac arrest ,Gender disparity ,Bystander ,Emergency medical services ,Medicine (General) ,R5-920 - Abstract
Summary: Background: Bystander cardiopulmonary resuscitation (BCPR) is a critical component of the 'chain of survival' in reducing mortality among out-of-hospital cardiac arrest (OHCA) victims. Inconsistent findings on gender disparities among adult recipients of layperson BCPR have been reported in the literature. We aimed to fill this knowledge gap by investigating the extent of gender disparities in a cross-national setting within Pan-Asian communities. Methods: We utilised data collected from the Pan-Asian Resuscitation Outcomes Study (PAROS), an international, multicentre, prospective study conducted between 2009 and 2018. We included all OHCA cases with non-traumatic arrest aetiology transported by emergency medical services and excluded study sites that did not consistently collect information about the location of cardiac arrest. Logistic regression was used to analyse the association between gender and BCPR, stratified by location. Findings: We analysed a cohort of 56,192 OHCA cases with an overall BCPR rate of 36.2% (20,329/56,192). At public locations, the BCPR rate was 31.2% (631/2022) for female and 36.4% (3235/8892) for male OHCA victims; while at home, the rate was 38.3% (6838/17,842) for females and 35.1% (9625/27,436) for males. Controlling for site differences and several factors in multivariable logistic regression, we found females less likely to receive BCPR than males in public locations (odds ratio [OR]=0.89, 95% confidence interval [CI]: 0.70–0.99), but more likely to receive BCPR at home (OR=1.16, 95% CI: 1.11–1.21). Interpretation: In Pan-Asian communities, gender differences exist in adult recipients of BCPR and differ between home and public locations. Future studies should account for additional information on bystanders and societal factors to identify targets for interventions. Funding: The study was supported by grants from the National Medical Research Council (NMRC/CSA/0049/2013) and Laerdal Foundation (20040).
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- 2022
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29. Integrated Genomic Profiling and Drug Screening of Patient-Derived Cultures Identifies Individualized Copy Number-Dependent Susceptibilities Involving PI3K Pathway and 17q Genes in Neuroblastoma
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Rachel L. Y. Wong, Megan R. E. Wong, Chik Hong Kuick, Seyed Ehsan Saffari, Meng Kang Wong, Sheng Hui Tan, Khurshid Merchant, Kenneth T. E. Chang, Matan Thangavelu, Giridharan Periyasamy, Zhi Xiong Chen, Prasad Iyer, Enrica E. K. Tan, Shui Yen Soh, N. Gopalakrishna Iyer, Qiao Fan, and Amos H. P. Loh
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neuroblastoma ,patient-derived culture ,copy number variations (CNV) ,Comprehensive genomic profiling (CGP) ,PI3K - AKT pathway ,CDK (cyclin-dependent kinase) ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Neuroblastoma is the commonest extracranial pediatric malignancy. With few recurrent single nucleotide variations (SNVs), mutation-based precision oncology approaches have limited utility, but its frequent and heterogenous copy number variations (CNVs) could represent genomic dependencies that may be exploited for personalized therapy. Patient-derived cell culture (PDC) models can facilitate rapid testing of multiple agents to determine such individualized drug-responses. Thus, to study the relationship between individual genomic aberrations and therapeutic susceptibilities, we integrated comprehensive genomic profiling of neuroblastoma tumors with drug screening of corresponding PDCs against 418 targeted inhibitors. We quantified the strength of association between copy number and cytotoxicity, and validated significantly correlated gene-drug pairs in public data and using machine learning models. Somatic mutations were infrequent (3.1 per case), but copy number losses in 1p (31%) and 11q (38%), and gains in 17q (69%) were prevalent. Critically, in-vitro cytotoxicity significantly correlated only with CNVs, but not SNVs. Among 1278 significantly correlated gene-drug pairs, copy number of GNA13 and DNA damage response genes CBL, DNMT3A, and PPM1D were most significantly correlated with cytotoxicity; the drugs most commonly associated with these genes were PI3K/mTOR inhibitor PIK-75, and CDK inhibitors P276-00, SNS-032, AT7519, flavopiridol and dinaciclib. Predictive Markov random field models constructed from CNVs alone recapitulated the true z-score-weighted associations, with the strongest gene-drug functional interactions in subnetworks involving PI3K and JAK-STAT pathways. Together, our data defined individualized dose-dependent relationships between copy number gains of PI3K and STAT family genes particularly on 17q and susceptibility to PI3K and cell cycle agents in neuroblastoma. Integration of genomic profiling and drug screening of patient-derived models of neuroblastoma can quantitatively define copy number-dependent sensitivities to targeted inhibitors, which can guide personalized therapy for such mutationally quiet cancers.
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- 2021
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30. Geospatial Analysis of Acute Poisonings at Mashhad, Iran in 2013
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Mohammad Taghi Shakeri, Seyed Ehsan Saffari, Bita Dadpour, Hossein Aghajani, Ali Hadianfar, and Reza Afshari
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poisoning ,iran ,spatial analysis ,spatial autocorrelation ,Toxicology. Poisons ,RA1190-1270 - Abstract
Background: Geospatial distribution analysis is a highly useful tool, especially in the field of health research and health economics. We aimed to study the geospatial distribution of poisoned patients and the risk factors in Mashhad, Iran. Methods: This was a retrospective cross-sectional study of patients treated at the Medical Toxicology Center, Imam Reza Hospital, Mashhad, Iran, which is the only referral center in northeast of Iran, in 2013. Negative binomial and Poisson approach via generalized linear mixed models were performed to investigate the association between socio-demographic characteristics with the number of reported cases of poisoning. Results: A total of 5064 poisoned patients (52% females) were included. Most of the poisoned patients were within the age group of 20-29 years old (41.4%). Pharmaceutical agents were the most common cause of poisonings (64.6%). The local test of spatial autocorrelation (Moran’s I) confirms that the poisoning had cluster pattern in Mashhad. Number of poisoning events were found to be associated with population density (RR= 1.00011; 95% CI 1.0001-1.00013), and the frequency of people with less than high school education (RR=1.49; 95% CI 1.32-1.68). Conclusion: The geospatial factors may have impact on the number of acute poisoning events in a city. Some parts of a city may exhibit spatial clustering in poisoning events. Once clusters are found, interventions can be focused to specific geographic locations and would be helpful for healthcare policymakers to focus on prevention programs.
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- 2019
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31. Prognosis of Guillain–Barré Syndrome Linked to COVID-19 Vaccination
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Shaun Kai Kiat Chua, Qian Ying Soh, Seyed Ehsan Saffari, and Eng-King Tan
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Guillain–Barré syndrome ,COVID-19 vaccination ,SARS-CoV-2 vaccination ,prognosis ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
There have been increasing reports of Guillain–Barré syndrome (GBS), a rare but debilitating neurological disease, occurring post-COVID-19 vaccination. However, the outcomes and relationships between patient demographics and clinical outcomes of post-COVID-19 vaccination GBS remain unclear. To bridge this gap, our study investigates the outcomes and clinical factors associated with poorer GBS outcomes following COVID-19 vaccination. We conducted a review and pooled analysis of detailed data extracted from 57 published cases with the relevant search strategies and criteria. The groups compared included male versus female patients, 1st dose versus 2nd dose and early onset versus late onset of GBS. Multivariate regression analysis was performed to compare the vaccine type, clinical severity and post-treatment outcomes between these groups of patients. Our results highlight for the first time that females were significantly more likely to have severe clinical presentation and poorer outcomes compared to males. Additionally, viral vector vaccines were the predominant vaccine type administered in early-onset post-COVID-19-vaccination GBS and GBS occurring after the 1st vaccination dose. It was also shown that reported cases of post-vaccination GBS generally displayed a positive response to conventional treatment and had favourable post-treatment outcomes. Through this study, we have established important links and provided assuring evidence for treatment response and post-treatment outcomes of GBS occurring post-COVID-19 vaccination. While the COVID-19 vaccination brings about much greater benefits than risks, our findings provide further impetus for greater vigilance in certain patient groups and more studies to explore the mechanisms behind these links.
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- 2022
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32. Factors affecting clinical outcomes in the management of melioidosis in Singapore: a 16-year case series
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Jaime Mei-Fong Chien, Seyed Ehsan Saffari, Ai-Ling Tan, and Thuan-Tong Tan
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Melioidosis ,B. pseudomallei ,Bacteremia ,Mortality ,Recurrent ,Singapore ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background Burkholderia pseudomallei is a gram negative bacteria that causes a spectrum of human diseases in the tropics. Although melioidosis is endemic in Southeast Asia, large clinical case series were rarely reported from metropolitan Singapore. Methods This is a retrospective study of 219 consecutive patients with culture proven infections due to Burkholderia pseudomallei between the years 2001 to 2016 managed in Singapore General Hospital (SGH). We aimed to review local patients’ characteristics and identify clinical factors associated with mortality and recurrent melioidosis. Results Culture proven melioidosis occurred in 219 patients, 83.1% were male with a mean age of 55.7 ± 14.3 years and 63.0% had diabetes mellitus. Most patients (71.7%) present within 4 weeks of symptom onset and the most common symptom was fever. The majority of patients had bacteremia (67.6%) and had infection involving the respiratory system (71.2%), presenting most frequently with multi-lobar pneumonia. Thirty-four (15.5%) deaths occurred during the initial hospitalisation with a median time from presentation to death of 6.0 days (interquartile range: 2.8–16.3). Twelve patients demised before the diagnosis of melioidosis was made. Univariate analysis identified patients with symptom duration of longer than 4 weeks, bacteremia, and disease requiring mechanical ventilation, inotropic support or temporary dialysis as factors that were significantly associated with mortality. Having bacteremia and disease requiring mechanical ventilation remained statistically significant factors in the multivariable analysis. Twenty-one (11.4%) patients developed at least 1 episode of culture proven recurrent infection, with 15 recurring within the first 12 months of their initial infection. Eight patients developed more than 1 episode of culture proven recurrent infection. Patients with multifocal infection were more likely to develop recurrent infection. Conclusion In metropolitan Singapore, melioidosis was associated with mortality in excess of 15%, where more than a third occurred before diagnosis. This study reminds local physicians that melioidosis is still a serious infection affecting local male diabetic patients and an important differential diagnosis in a patient presenting with severe multi-lobar pneumonia and septic shock. Recurrent infections occurred in 11.4% and the weight-based dosing of oral eradication antibiotics may improve the management of this disease locally.
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- 2018
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33. Application of the Truncated Zero-Inflated Double Poisson for Determining of the Effecting Factors on the Number of Coronary Artery Stenosis.
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Arezoo Orooji, Toktam Sahranavard, Mohammad-Taghi Shakeri, Mohammad Tajfard, and Seyed Ehsan Saffari
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- 2022
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34. Handling missing values in healthcare data: A systematic review of deep learning-based imputation techniques.
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Mingxuan Liu, Siqi Li 0004, Han Yuan, Marcus Eng Hock Ong, Yilin Ning, Feng Xie 0004, Seyed Ehsan Saffari, Victor Volovici, Bibhas Chakraborty, and Nan Liu 0003
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- 2022
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35. Handling missing values in healthcare data: A systematic review of deep learning-based imputation techniques.
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Mingxuan Liu, Siqi Li 0004, Han Yuan, Marcus Eng Hock Ong, Yilin Ning, Feng Xie 0004, Seyed Ehsan Saffari, Yuqing Shang, Victor Volovici, Bibhas Chakraborty, and Nan Liu 0003
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- 2023
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36. Usefulness of the Visual Cognitive Assessment Test in Detecting Mild Cognitive Impairment in the Community
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See Ann Soo, Dilip Kumar, Yi Jin Leow, Chen Ling Koh, Seyed Ehsan Saffari, and Nagaendran Kandiah
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Psychiatry and Mental health ,Clinical Psychology ,General Neuroscience ,General Medicine ,Geriatrics and Gerontology - Abstract
Background: A delay in the detection of mild cognitive impairment (MCI) in the community delays the opportunity for early intervention. Accurate tools to detect MCI in the community are lacking. The Visual Cognitive Assessment Test (VCAT) is a visual based cognitive test useful for multilingual populations without the need for translation. Objective: Here, we evaluate the usefulness of VCAT in detecting MCI in a community population in Singapore. Methods: We recruited 301 participants from the community who completed a detailed neuropsychological assessment and 170 of them completed a 3T magnetic resonance imaging (MRI) brain scan. We performed a receiver operating characteristics analysis to test the diagnostic performance of VCAT compared to Montreal Cognitive Assessment (MoCA) in distinguishing MCI from cognitively normal (CN) by measuring area under the curve (AUC). To test for the association of VCAT with structural MRI, we performed a Pearson’s correlation analysis for VCAT and MRI variables. Results: We recruited 39 CN and 262 MCI participants from Dementia Research Centre (Singapore). Mean age of the cohort was 63.64, SD = 9.38, mean education years was 13.59, SD = 3.70 and majority were women (55.8%). VCAT was effective in detecting MCI from CN with an AUC of 0.794 (95% CI 0.723–0.865) which was slightly higher than MoCA 0.699 (95% CI 0.621–0.777). Among subjects with MCI, VCAT was associated with medial temporal lobe atrophy (ρ = –0.265, p = 0.001). Conclusions: The VCAT is useful in detecting MCI in the community in Singapore and may be an effective measure of neurodegeneration.
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- 2023
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37. AutoScore-Imbalance: An interpretable machine learning tool for development of clinical scores with rare events data.
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Han Yuan, Feng Xie 0004, Marcus Eng Hock Ong, Yilin Ning, Marcel Lucas Chee, Seyed Ehsan Saffari, Hairil Rizal Abdullah, Benjamin Alan Goldstein, Bibhas Chakraborty, and Nan Liu 0003
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- 2021
38. COVID-19 infection after SARS-CoV-2 mRNA vaccination in Multiple Sclerosis, AQP4-antibody NMOSD and MOGAD patients during the Omicron subvariant BA.1/2 wave in Singapore
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Tianrong Yeo, Rachel Wan En Siew, Muhammad Yaaseen Gulam, Janis Siew Noi Tye, Amelia Yun Yi Aw, Thanushiree Sivalingam, Xuejuan Peng, Kok Pin Yong, Seyed Ehsan Saffari, Yinxia Chao, and Kevin Tan
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Neurology ,Neurology (clinical) - Published
- 2023
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39. Plasma Soluble ST2 Levels Are Higher in Neurodegenerative Disorders and Associated with Poorer Cognition
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Yi Jayne Tan, Isabel Siow, Seyed Ehsan Saffari, Simon K.S. Ting, Zeng Li, Nagaendran Kandiah, Louis C.S. Tan, Eng King Tan, and Adeline S.L. Ng
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Psychiatry and Mental health ,Clinical Psychology ,General Neuroscience ,General Medicine ,Geriatrics and Gerontology - Abstract
Background: Suppressor of tumorgenicity 2 (ST2) is highly expressed in brain tissue and is a receptor for interleukin 33 (IL-33). ST2 exists in two forms, a transmembrane receptor (ST2L) and a soluble decoy receptor (sST2). IL-33 binds to ST2L, triggering downstream signaling pathways involved in amyloid plaque clearance. Conversely, sST2 binds competitively to IL-33, attenuating its neuroprotective effects. High sST2 levels have been reported in mild cognitive impairment (MCI) and Alzheimer’s disease (AD), suggesting that the IL-33/ST2 signaling pathway may be implicated in neurodegenerative diseases. Objective: To investigate plasma sST2 levels in controls and patients with MCI, AD, frontotemporal dementia (FTD), and Parkinson’s disease (PD). Methods: Plasma sST2 levels were measured using ELISA in 397 subjects (91 HC, 46 MCI, 38 AD, 28 FTD, and 194 PD). Cerebrospinal fluid (CSF) levels of sST2 were measured in 22 subjects. Relationship between sST2 and clinical outcomes were analyzed. Results: Plasma sST2 levels were increased across all disease groups compared to controls, with highest levels seen in FTD followed by AD and PD. Dementia patients with higher sST2 had lower cross-sectional cognitive scores in Frontal Assessment Battery and Digit Span Backward. At baseline, PD-MCI patients had higher sST2, associated with worse attention. In the longitudinal PD cohort, higher sST2 significantly associated with decline in global cognition and visuospatial domains. Plasma sST2 levels correlated with CSF sST2 levels. Conclusion: Plasma sST2 is raised across neurodegenerative diseases and is associated with poorer cognition. Higher baseline sST2 is a potential biomarker of disease severity in neurodegeneration.
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- 2023
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40. Endoscopic third ventriculostomy for shunt malfunction in the pediatric population: a systematic review, meta-analysis, and meta-regression analysis
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Keng Siang Lee, Aswin Chari, Conor S. Gillespie, Justyna O. Ekert, Seyed Ehsan Saffari, Greg James, and Kristian Aquilina
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General Medicine - Abstract
OBJECTIVE Despite growing published evidence of the merits of endoscopic third ventriculostomy (ETV) instead of shunt revision at the time of shunt malfunction (secondary ETV), concerns about its efficacy and complications remain and ETV is still not used widely in this context. This study aimed to carry out a comprehensive meta-analysis and reports on the success and safety of secondary ETV in the pediatric age group. METHODS In accordance with the PRISMA guidelines, systematic searches of Medline, Embase, and Cochrane Central were undertaken from database inception to September 7, 2022. ETV success was defined as the lack of need for a shunt and was the primary outcome measure. Secondary outcome measures were the rates of complications and mortality. A random-effects model was used. Summary-level meta-regression was performed to identify predictors for success in accordance with the ETV Success Score (ETVSS). RESULTS Sixteen studies reporting on 584 patients who underwent secondary ETV for shunt malfunction were included in the meta-analysis. The overall pooled mean (95% CI) age was 6.1 (3–9) years, and 57.0% of patients were male. The pooled prevalence rates of the hydrocephalus etiologies were as follows: aqueduct stenosis (39.3%); myelomeningocele (27.6%); postinfectious (17.1%); posthemorrhagic (13.0%); neoplasm (13.0%); and malformation (11.3%). The overall pooled success rates of ETV for shunt malfunction at 3 months, 6 months, and 12 months were 65.69% (95% CI 52%–77%, prediction interval 47%–81%, I2 = 0, p = 0.775); 63.25% (95% CI 54%–72%, prediction interval 38%–83%, I2 = 65, p < 0.001); and 53.37% (95% CI 24%–81%, prediction interval 1%–99%, I2 = 47, p = 0.154). The overall pooled prevalence of intraoperative bleeding was 4.96% (95% CI 0%–64%, prediction interval 0%–99%, I2 = 85, p < 0.001). The overall rates of complications were low, with new neurological deficit (transient or permanent) having the highest rate at 1.61% (95% CI 0.68%–3.72%, prediction interval 0.67%–3.78%, I2 = 0, p > 0.999). On meta-regression, age (p = 0.138), proportion of patients with postinfectious hydrocephalus (p = 0.8736), and number of shunt revisions (p = 0.1775) were not statistically significant predictors of secondary ETV success at 6 months. CONCLUSIONS This meta-analysis demonstrates that secondary ETV after shunt malfunction in pediatric patients is a feasible option with acceptable success rates and low complication rates. Clinical trial registration no.: CRD42022359573 (PROSPERO)
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- 2023
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41. AutoScore-Imbalance: An interpretable machine learning tool for development of clinical scores with rare events data.
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Han Yuan, Feng Xie 0004, Marcus Eng Hock Ong, Yilin Ning, Marcel Lucas Chee, Seyed Ehsan Saffari, Hairil Rizal Abdullah, Benjamin Alan Goldstein, Bibhas Chakraborty, and Nan Liu 0003
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- 2022
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42. Characteristics and Postoperative Outcomes for High Cervical versus Subaxial Cervical Intradural Extramedullary Tumors: A Multicenter Study
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Lester Lee, Srujana Venkata Vedicherla, Daniel Loh, Seyed Ehsan Saffari, Justin Ker, Krishan Kumar, Beatrice Jun-Nian Tan, Shree Kumar Dinesh, Ji Min Ling, and Colum Nolan
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Surgery ,Neurology (clinical) - Abstract
High cervical intradural extramedullary tumors are uncommon. Their relationship to surrounding neural structures and vertebral arteries makes surgical excision challenging. No previous studies have compared high cervical to subaxial cervical intradural extramedullary spinal tumors to elucidate their unique characteristics and surgical outcomes.We performed a retrospective study in which patients who underwent excision of a cervical intradural extramedullary tumor were divided into a high cervical group and a subaxial cervical group. Variables included sex, age, Charlson Comorbidity Index, volume, laterality, preoperative weakness, use of neuromonitoring and drains, instrumented fusion, complications, length of stay, histology, discharge location, recurrence, and duration of follow-up. Variables were compared between the 2 groups. Limb power and Nurick classification were charted preoperatively, at discharge, and at 6 months to plot their recovery trajectory.Eighty-four patients with a total of 90 tumors were enrolled, including 40 patients in the high cervical group and 44 patients in the subaxial spine group. More patients with neurofibromas (P = 0.011) and bilateral tumors (P = 0.044) were in the high cervical group. A greater prevalence of neurofibromatosis type 1 was significant for bilateral high cervical tumors (P = 0.033). More patients in the subaxial group had instrumented fusion (P = 0.045). More patients in the high cervical group had improvement in limb power (P = 0.025) and Nurick classification (P = 0.0001) postoperatively before discharge. By 6 months, both groups had similar recovery. No mortality was attributable to surgery in either group.High cervical intradural extramedullary spine tumors have more bilateral tumors associated with neurofibromatosis type 1. Despite the challenging anatomy, surgical resection is safe with good outcomes in this group.
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- 2023
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43. Handling missing values in healthcare data
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Mingxuan Liu, Siqi Li, Han Yuan, Marcus Eng Hock Ong, Yilin Ning, Feng Xie, Seyed Ehsan Saffari, Yuqing Shang, Victor Volovici, Bibhas Chakraborty, and Nan Liu
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Artificial Intelligence ,Medicine (miscellaneous) - Abstract
Objective: The proper handling of missing values is critical to delivering reliable estimates and decisions, especially in high-stakes fields such as clinical research. In response to the increasing diversity and complexity of data, many researchers have developed deep learning (DL)-based imputation techniques. We conducted a systematic review to evaluate the use of these techniques, with a particular focus on the types of data, intending to assist healthcare researchers from various disciplines in dealing with missing data. Materials and methods: We searched five databases (MEDLINE, Web of Science, Embase, CINAHL, and Scopus) for articles published prior to February 8, 2023 that described the use of DL-based models for imputation. We examined selected articles from four perspectives: data types, model backbones (i.e., main architectures), imputation strategies, and comparisons with non-DL-based methods. Based on data types, we created an evidence map to illustrate the adoption of DL models. Results: Out of 1822 articles, a total of 111 were included, of which tabular static data (29 %, 32/111) and temporal data (40 %, 44/111) were the most frequently investigated. Our findings revealed a discernible pattern in the choice of model backbones and data types, for example, the dominance of autoencoder and recurrent neural networks for tabular temporal data. The discrepancy in imputation strategy usage among data types was also observed. The “integrated” imputation strategy, which solves the imputation task simultaneously with downstream tasks, was most popular for tabular temporal data (52 %, 23/44) and multi-modal data (56 %, 5/9). Moreover, DL-based imputation methods yielded a higher level of imputation accuracy than non-DL methods in most studies. Conclusion: The DL-based imputation models are a family of techniques, with diverse network structures. Their designation in healthcare is usually tailored to data types with different characteristics. Although DL-based imputation models may not be superior to conventional approaches across all datasets, it is highly possible for them to achieve satisfactory results for a particular data type or dataset. There are, however, still issues with regard to portability, interpretability, and fairness associated with current DL-based imputation models.
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- 2023
44. Plasma Neurofilament Light Concentration Is Associated with Diffusion-Tensor MRI-Based Measures of Neurodegeneration in Early Parkinson’s Disease
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Thomas, Welton, Yi Jayne, Tan, Seyed Ehsan, Saffari, Samuel Y E, Ng, Nicole S Y, Chia, Alisa C W, Yong, Xinyi, Choi, Dede Liana, Heng, Yao-Chia, Shih, Septian, Hartono, Weiling, Lee, Zheyu, Xu, Kay Yaw, Tay, Wing Lok, Au, Eng-King, Tan, Ling Ling, Chan, Adeline S L, Ng, and Louis C S, Tan
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Cellular and Molecular Neuroscience ,Diffusion Tensor Imaging ,Neurofilament Proteins ,Intermediate Filaments ,Humans ,Parkinson Disease ,Neurology (clinical) ,Magnetic Resonance Imaging ,Biomarkers - Abstract
Background: Neurofilament light is a marker of axonal degeneration, whose measurement from peripheral blood was recently made possible by new assays. Objective: We aimed to determine whether plasma neurofilament light chain (NfL) concentration reflects brain white matter integrity in patients with early Parkinson’s disease (PD). Methods: 137 early PD patients and 51 healthy controls were included. Plasma NfL levels were measured using ultrasensitive single molecule array. 3T MRI including diffusion tensor imaging was acquired for voxelwise analysis of association between NfL and both fractional anisotropy (FA) and mean diffusivity (MD) in white matter tracts and subcortical nuclei. Results: A pattern of brain microstructural changes consistent with neurodegeneration was associated with increased plasma NfL in most of the frontal lobe and right internal capsule, with decreased FA and increased MD. The same clusters were also associated with poorer global cognition. A significant cluster in the left putamen was associated with increased NfL, with a significantly greater effect in PD than controls. Conclusion: Plasma NfL may be associated with brain microstructure, as measured using diffusion tensor imaging, in patients with early PD. Higher plasma NfL was associated with a frontal pattern of neurodegeneration that also correlates with cognitive performance in our cohort. This may support a future role for plasma NfL as an accessible biomarker for neurodegeneration and cognitive dysfunction in PD.
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- 2022
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45. Association Between Parkinson’s Disease and Coronary Artery Disease: A Systematic Review and Meta-Analysis
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Shaun Kai Kiat Chua, Seyed Ehsan Saffari, Selene Joon Yan Lee, and Eng-King Tan
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Observational Studies as Topic ,Cellular and Molecular Neuroscience ,Case-Control Studies ,Humans ,Parkinson Disease ,Coronary Artery Disease ,Neurology (clinical) - Abstract
Background: The relationship between Parkinson’s disease (PD) and coronary artery disease (CAD) is unclear. Objective: This study aims to investigate whether PD and CAD are associated through systematic review and meta-analysis of observational studies. Methods: Electronic database search of PubMed, EMBASE, and Web of Science for observational studies published from 1 January 2010 to 1 August 2021 was conducted using terms related to PD and CAD. Unadjusted risk ratios (RR) and odds ratios (OR) of included cohort and case-control studies respectively were used to ascertain the association between PD and CAD. Study heterogeneity was evaluated using the I2 test. Results: Forty-one full-text studies were initially retrieved for eligibility assessment. Five studies that satisfied the inclusion criteria, consisting of three cohort and two case-control studies, were eventually included in this meta-analysis. The five studies enrolled 35,237 PD patients and 650,866 non-PD patients. PD and CAD were found to be significantly associated in cohort studies (RR = 2.23, 95% CI = 1.08–4.59, p = 0.03; Fig. 2), which held after sensitivity analysis (RR = 1.45, 95% CI = 1.31–1.60, p
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- 2022
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46. Nailfold capillaroscopy for the early diagnosis of the scleroderma spectrum of diseases in patients without Raynaud’s phenomenon
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Cassandra Hong, Ling Xiang, Seyed Ehsan Saffari, and Andrea HL Low
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integumentary system ,Rheumatology ,Original Research Articles ,Immunology ,Immunology and Allergy - Abstract
Background: The utility of nailfold capillaroscopy in the evaluation of patients without Raynaud’s phenomenon is unclear. Objective: This study aims to compare the utility of nailfold capillaroscopy for the early diagnosis of the scleroderma-spectrum of diseases in patients who present with Raynaud’s phenomenon, undifferentiated non-Raynaud’s phenomenon features and positive systemic sclerosis-associated antibodies without scleroderma-spectrum of disease features. Methods: Eligible patients were divided into three referral criteria groups: (I) Raynaud’s phenomenon; (II) Undifferentiated non-Raynaud’s phenomenon features and (III) Positive systemic sclerosis-associated autoantibodies without features to suggest scleroderma-spectrum of diseases. This includes systemic sclerosis, mixed connective tissue disease and dermatomyositis. The association between baseline scleroderma pattern on nailfold capillaroscopy (systemic sclerosis–nailfold capillaroscopy) and final diagnosis at follow-up was determined using logistic regression analysis. Test characteristics of nailfold capillaroscopy were compared and stratified by referral groups. Results: Of 95 patients followed-up for a mean of 1.6 years, 28 (29.5%) patients developed scleroderma-spectrum of diseases, 36 (37.9%) patients had suspected/other connective tissue disease and 27 (28.4%) patients had no connective tissue disease. Baseline systemic sclerosis-nailfold capillaroscopy was significantly associated with the development of scleroderma-spectrum of diseases in patients from Group I (odds ratio, 7.1, p = 0.01) and Group II (odds ratio 7.3, p = 0.005). In Group II patients, nailfold capillaroscopy had a sensitivity, specificity, positive and negative predictive values of 71.4%, 76.5%, 55.6% and 86.7%, respectively. Specificity (81.8%) and PPV (69.2%) were the highest in Group I patients. Nailfold capillaroscopy had the highest negative predictive value in Group III (100%), followed by Group II (86.7%) and Group I (78.3%) patients. Conclusion: In addition to evaluating patients with Raynaud’s phenomenon, nailfold capillaroscopy was useful in the evaluation and exclusion of scleroderma-spectrum of diseases in patients with undifferentiated non-Raynaud phenomenon features and those with systemic sclerosis-associated antibodies without features to suggest scleroderma-spectrum of diseases.
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- 2022
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47. Longitudinal Study of SNCA Rep1 Polymorphism on Executive Function in Early Parkinson’s Disease
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Yi Jayne Tan, Seyed Ehsan Saffari, Yi Zhao, Ebonne Y.L. Ng, Alisa C.W. Yong, Samuel Y.E. Ng, Nicole S.Y. Chia, Xinyi Choi, Dede Heng, Shermyn Neo, Zheyu Xu, Kay Yaw Tay, Wing Lok Au, Eng-King Tan, Louis C.S. Tan, and Adeline S.L. Ng
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Executive Function ,Cellular and Molecular Neuroscience ,Polymorphism, Genetic ,alpha-Synuclein ,Humans ,Genetic Predisposition to Disease ,Parkinson Disease ,Longitudinal Studies ,Neurology (clinical) - Abstract
The alpha-synuclein gene promoter (SNCA-Rep1) is associated with Parkinson’s disease (PD), but its relationship with performance across individual cognitive domains in early PD is unknown. This study aims to investigate Rep1 polymorphism and longitudinal change in cognition in early PD. In this longitudinal study, Rep1 allele lengths (“long” and “short”) were determined in 204 early PD patients. All participants underwent annual neuropsychological assessments and followed up for 3 years. Linear-mixed model was performed to investigate the association of Rep1 status and longitudinal change in individual cognitive domains. At 3 years, significant decline in executive function was observed in long Rep1 allele carriers vs short allele carriers, controlling for potential confounders. This is the first longitudinal study demonstrating that long Rep1 allele carriers are at higher risk for executive dysfunction in early PD.
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- 2022
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48. Parkinson’s disease and cancer: a systematic review and meta-analysis on the influence of lifestyle habits, genetic variants, and gender
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Joon Yan Selene Lee, Jing Han Ng, Seyed Ehsan Saffari, and Eng-King Tan
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Male ,Habits ,Aging ,Brain Neoplasms ,Humans ,Female ,Parkinson Disease ,Cell Biology ,Colorectal Neoplasms ,Life Style ,Melanoma - Abstract
The relationship between Parkinson's disease (PD) and cancer has been debated. Gender and genetic influences on cancer development in PD is unclear.Using QUOROM guidelines, we conducted a systematic review and meta-analysis on potential clinical and genetic factors influencing the PD and subsequent cancer relationship. English articles published in PubMed, Web of Science, and SCOPUS from 2010 to 30 August 2020 were considered for suitability.Of 46 studies identified, fourteen satisfied the inclusion criteria and were further analysed. Unadjusted risk ratios (RR) and 95% confidence intervals were computed to determine the PD and cancer relationship. PD patients have decreased subsequent cancer risks (RR = 0.87, 95% CI = 0.81-0.93), reduced risks of colon, rectal, and colorectal cancer (RR = 0.77, 95% CI = 0.63-0.94), lung cancer (RR = 0.62, 95% CI = 0.48-0.80), and increased brain cancer (R = 1.48, 95% CI = 1.02-2.13) and melanoma risk (R = 1.76, 95% CI = 1.23-2.50). Compared to idiopathic PD, LRRK2-G2019S carriers had increased general cancer risks (RR = 1.26, 95% CI = 1.09-1.46), particularly brain (RR = 2.41, 95% CI = 1.06-5.50), breast (RR = 2.57, 95% CI = 1.19-5.58), colon (RR = 1.83, 95% CI = 1.13-2.99), and haematological cancers (RR = 2.05, 95% CI = 1.07-3.92). Female PD patients have decreased general cancer risks compared to male PD patients in this analysis (RR = 0.83, 95% CI = 0.69-0.98).PD patients have reduced risks of colon, rectal, colorectal cancer and lung cancers and increased risks of brain cancer and melanoma. LRRK2-G2019S carriers have increased cancer risks, particularly brain, breast, colon and blood cancers. Female gender was associated with reduced risks. The role of ethnicity, comorbidities, and lifestyle habits on PD patients' subsequent cancer risk should be further investigated.
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- 2022
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49. Postoperative Rather Than Preoperative Neutropenia Is Associated With Early Catheter-related Bloodstream Infections in Newly Diagnosed Pediatric Cancer Patients
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York Tien Lee, Chin-Bee Tan, Joyce Ching Mei Lam, Seyed Ehsan Saffari, Vanessa Yin Woan Lee, Amos Hong Pheng Loh, Rachel Wang, Wen Qi Cher, Chia Yin Chong, and Sue-Mei Cheah
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Male ,Microbiology (medical) ,medicine.medical_specialty ,Neutropenia ,Adolescent ,Bacteremia ,hemic and lymphatic diseases ,Internal medicine ,White blood cell ,medicine ,Central Venous Catheters ,Humans ,Antibiotic prophylaxis ,Child ,Perioperative Period ,Retrospective Studies ,Leukemia ,business.industry ,Incidence (epidemiology) ,Infant ,Myeloid leukemia ,Odds ratio ,Perioperative ,Antibiotic Prophylaxis ,medicine.disease ,Pediatric cancer ,Infectious Diseases ,medicine.anatomical_structure ,Catheter-Related Infections ,Child, Preschool ,Pediatrics, Perinatology and Child Health ,Female ,business - Abstract
BACKGROUND The relationship of early catheter-related bloodstream infections (CRBSIs) with perioperative neutropenia and antibiotic prophylaxis is not well established. We sought to evaluate perioperative factors associated with early CRBSIs in newly diagnosed pediatric cancer patients, particularly hematological indices and antibiotic use. METHODS We retrospectively reviewed national registry records of newly diagnosed pediatric cancer patients with port-a-caths inserted using standardized perioperative protocols where only antibiotic use was not regulated. Thirty-day postoperative CRBSI incidence was correlated with preoperative factors using logistic regression and with postoperative blood counts using linear trend analysis. RESULTS Among 243 patients, 17 CRBSIs (7.0%) occurred at median 14 (range, 8-28) postoperative days. Early CRBSIs were significantly associated with cancer type [acute myeloid leukemia and other leukemias (AML/OLs) vs. solid tumors and lymphomas (STLs): odds ratio (OR), 5.09; P = 0.0036; acute lymphoblastic leukemia vs. STL: OR 0.83; P = 0.0446] but not preoperative antibiotics, absolute neutrophil counts and white blood cell counts. Thirty-day postoperative absolute neutrophil counts and white blood cell trends differed significantly between patients with acute lymphoblastic leukemia and STLs (OR 0.83, P < 0.05) and between AML/OLs and STLs (OR 5.09, P < 0.005), with AML/OL patients having the most protracted neutropenia during this period. CONCLUSIONS Contrary to common belief, low preoperative absolute neutrophil counts and lack of preoperative antibiotics were not associated with higher early CRBSI rates. Instead, AML/OL patients, particularly those with prolonged neutropenia during the first 30 postoperative days, were at increased risk. Our findings do not support the use of empirical preoperative antibiotics and instead identify prolonged postoperative neutropenia as a major contributing factor for early CRBSI.
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- 2022
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50. Lower white matter hyperintensity is associated with lower mild behavioral impairment severity among pre‐dementia people with higher education attainment
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See Ann Soo, Kok Pin Ng, Dilip Kumar, Seyed Ehsan Saffari, and Nagaendran Kandiah
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Psychiatry and Mental health ,Cellular and Molecular Neuroscience ,Developmental Neuroscience ,Epidemiology ,Health Policy ,Neurology (clinical) ,Geriatrics and Gerontology - Published
- 2022
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