ORCID Profile
0000-0002-8461-0601
Current Organisation
Fiona Stanley Hospital
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Publisher: Informa UK Limited
Date: 04-2015
DOI: 10.2147/CIA.S73563
Publisher: Elsevier BV
Date: 05-2015
DOI: 10.1016/J.PARKRELDIS.2015.02.014
Abstract: Existing literature on brain volumetric alterations in patients with Parkinson's disease (PD) have mainly focused on gray matter (GM) and are largely cross-sectional. Little is known about white matter (WM) volumetric features and their impact on cognitive symptoms in PD. Therefore, the present study aims to examine both GM and WM volumes of cognitively asymptomatic PD patients with a longitudinal design. A total of 42 cognitively asymptomatic patients with early stage PD were recruited and followed up for 1.5 years. At follow-up, 12 patients progressed to mild cognitive impairment (MCI) and were classified as "converters" while the remaining 30 patients remained cognitively asymptomatic and were classified as "non-converters". All patients underwent clinical and neuropsychological assessments as well as MRI scans at baseline and at follow-up. At baseline, non-converters and converters had comparable cognitive scores. At follow-up, converters showed more deficits in frontal-related cognitive function than non-converters. Volumetric analyses revealed that converters had more longitudinal reduction in WM, but not GM, volume compared to non-converters. The decreased volumes among converters were mainly localized in the frontal areas. Moreover, baseline global WM volume significantly predicted conversion to PD-MCI, while baseline GM and WM volumes of the frontal and parietal regions were associated with frontal cognitive changes across time. PD patients who develop MCI demonstrate longitudinal reduction in WM volume, especially in the frontal areas. While both regional GM and WM volumes associate with frontal cognitive decline, baseline global WM volume may be a neuroimaging marker of conversion to PD-MCI.
Publisher: Wiley
Date: 06-09-2019
Abstract: Gestational diabetes mellitus (GDM) and caesarean deliveries independently increase the risk of postoperative complications. There are limited data on the influence of insulin use on the outcomes of neonates who were delivered via caesarean section. We sought to investigate the impact of insulin use in women with GDM on resuscitation rates of infants post caesarean delivery. A retrospective database review of women with singleton term (≥ 37 weeks) pregnancies who were on insulin for GDM delivering between January 2005 and December 2014 at a major metropolitan hospital in Sydney. One thousand eight hundred and fifty-seven women with GDM were identified. The mean age was 31.01 ± 5.63 years and mean gestational period of 39.07 ± 1.00 weeks. 31.0% received insulin treatment for GDM. Women who were on insulin were older (31.9 ± 5.7 vs 30.6 ± 5.6 years, P < 0.001), had a higher body mass index (BMI) (31.2 ± 7.7 vs 29.0 ± 7.4 kg/m2, P < 0.001), higher rates of preecl sia (7.3% vs 4.1%, P = 0.004), lower rates of alcohol consumption (0.4% vs 1.7%, P = 0.014), and had infants with lower resuscitation rates (21.2% vs 28.6%, P = 0.001). Infants who required resuscitation had a lower gestational age, lower five-minute APGAR score, and lower birth weight, length, and head circumferences. On multivariate analysis, women with GDM treated with insulin (odds ratio [OR] = 0.69, CI = 0.54-0.89, P = 0.004), higher gestational age (OR = 0.88, CI = 0.78-0.99, P = 0.032), higher maternal BMI (OR = 1.02, CI = 1.01-1.04, P = 0.005), and emergency caesarean (OR = 2.33, CI = 1.74-3.12, P < 0.001) independently predicted incidence of resuscitation. The findings suggest a relationship between insulin use and reduced resuscitation rates of infants born from mothers with GDM. Further studies investigating the role, dosage, and criteria for insulin use in women with GDM are required.
Publisher: Cold Spring Harbor Laboratory
Date: 07-09-2021
DOI: 10.1101/2021.08.31.21262750
Abstract: The pericapsular nerve group (PENG) block was first described for the treatment of hip fracture, including neck of femur, in 2018. We hypothesise that the PENG block is safe and effective for patients with hip fracture when provided by emergency physicians and trainees in the emergency department (ED), for which it may be superior to fascia iliaca compartment block (FICB) and femoral nerve block (FNB). From October 2019 to July 2020, consecutive patients receiving regional anaesthesia for hip fracture in the ED of a single large regional hospital were prospectively enrolled. Pain scores were assessed prior to regional anaesthesia then at 15, 30 and 60 minutes after regional anaesthesia. Maximal reduction in pain scores within 60 minutes were assessed using the Visual Analogue Scale (at rest and on movement) or the Pain Assessment IN Advanced Dementia tool (at rest). Patients were followed for opioid use for 12 hours after regional anaesthesia and adverse events over the duration of their admission. There were 67 eligible patients during the enrolment period, with 52 (78%) prospectively enrolled. Thirty-three received femoral blocks (19 FICB, 14 FNB) and 19 received a PENG block. There was no difference in maximum pain score reduction between the groups whether measured at rest or on movement. Clinicians providing the PENG block were less experienced in the technique than those providing FICB or FNB. There was no difference in adverse effects between groups. Although opioid use was similar between the groups, more patients were opioid free after a PENG block. Although there was no difference in maximal pain score reduction, this study demonstrated that the PENG block was feasible and could be provided safely and effectively to patients with hip fracture in the ED. On this basis, a larger randomised controlled study should now be designed. What is already known on this subject □ There is a solid neuroanatomical rationale to suggest the PENG block may provide superior anaesthesia of hip fractures than FNB or FICB. □ The technique utilises bony sonographic and tactile landmarks which make it an ideal block for emergency physicians to safely and effectively perform. □ What this study adds □ This is the first comparative study of the PENG block to FNB or FICB in patients with hip fracture in ED, which will provide a scaffold for future research. □ This pragmatic observation of evolving practice showed that emergency physicians and trainees inexperienced in the technique could provide it safely and effectively in the ED
Publisher: Wiley
Date: 10-2014
DOI: 10.1111/JGS.13034
Publisher: Wiley
Date: 07-2014
Publisher: Elsevier BV
Date: 12-2016
DOI: 10.1016/J.JNS.2016.10.021
Abstract: Anxiety is prevalent in patients with Parkinson's disease (PD) and may affect patients' quality of life. Yet, little is known about the neural basis of anxiety in PD, and none have used a longitudinal design. 73 patients with mild PD were recruited and followed up for 18months. A whole-brain analysis was first used to identify brain regions associated with anxiety symptoms, followed by a regional analysis focusing on a priori hypothesised regions at baseline. A multivariate generalized estimating equations analysis was then conducted to determine the longitudinal association between grey matter (GM) volumetric changes of these significant regions and changes of anxiety symptoms. At baseline, anxiety symptom severity was associated with decreased GM volumes in the bilateral precuneus and anterior cingulate cortex (ACC). Over 18months, increased severity of anxiety symptoms was associated with decreased GM volume in the left precuneus and ACC, independent of age, gender, education, depressive symptom severity or use of psychiatric medication. These results mainly implicate the precuneus and ACC in the pathogenesis of anxiety in PD. We speculate that these structural changes could reflect the disrupted default mode network due to PD pathology, contributing to spontaneous anxiety-related self-focused thoughts.
Publisher: Springer Science and Business Media LLC
Date: 29-09-2017
DOI: 10.1038/S41598-017-12755-Z
Abstract: Post-stroke cognitive impairment (PSCI) warrants early detection and management. We sought to develop a risk score for screening patients at bedside for risk of delayed PSCI. Ischemic stroke survivors with PSCI and no cognitive impairments (NCI) 3–6 months post-stroke were studied to identify candidate variables predictive of PSCI. These variables were used to develop a risk score using regression models. The score, and the best identified clinical cutoff point, underwent development, stability testing, and internal and external validation in three independent cohorts from Singapore and Hong Kong. Across 1,088 subjects, the risk score, dubbed CHANGE, had areas under the receiver operating characteristics curve (AUROC) from 0.74 to 0.82 in detecting significant risk for PSCI, and had predicted values following actual prevalence. In validation data 3–6 and 12–18 months post-stroke, subjects with low, medium, and high scores had PSCI prevalence of 7–23%, 25–58%, and 67–82%. CHANGE was effective in screening ischemic stroke survivors for significant risk of developing PSCI up to 18 months post-stroke. CHANGE used readily available and reliable clinical data, and may be useful in identifying at-risk patients for PSCI.
Publisher: Elsevier BV
Date: 09-2015
DOI: 10.1016/J.PARKRELDIS.2015.06.014
Abstract: Studies have suggested a relationship between non-motor symptoms with motor fluctuations in patients with Parkinson's disease (PD). We studied the influence of depression on longitudinal motor and cognitive function among mild PD patients. A 1.5 years longitudinal study of 102 patients with mild idiopathic PD. Patients were assessed with a standardized clinical assessment battery including motor and non-motor scales. Patients also underwent serial neurocognitive testing that assessed global cognition, memory, attention, language, visuospatial and executive function. 81 patients with mean age of 64.9(SD = 7.9) years and mean Hoehn & Yahr of 1.9(SD = 0.4) completed baseline and follow-up visits. 22 patients had clinically significant depression at baseline with mean Geriatric Depression Scale of 6.9(SD = 2.4). These patients presented with concomitant apathy and anxiety and were more likely to be females with longer duration of PD. At baseline, patients with depression had poorer performance on global cognition and all cognitive domains although not significantly different from patients without depression. At follow-up, there was no statistically significant difference on cognitive performance between those with and without baseline depression. Patients with baseline depression demonstrated worsening of motor function after 18 months (UPDRS Motor Score Change: +5.0[7.0]vs.+0.2[7.3] p = 0.015). On multivariate analysis Baseline Motor Score (B = -0.229,CI = -0.445 to-0.013,p = 0.038), Baseline GDS (B = 0.622,CI = 0.078 to 1.166,p = 0.026) and PD duration (B = 0.520,CI = 0.105 to 0.935,p = 0.015) independently predicted increase in UPDRS Motor Score. The findings suggest a relationship between early depression with motor worsening and cognition decline in PD patients. Further biomarker-supported studies investigating the role of depression on motor and cognitive function are needed.
Publisher: Elsevier BV
Date: 02-2016
DOI: 10.1016/J.PARKRELDIS.2015.12.004
Abstract: Apathy is one of the most common behavioural disorders in Parkinson's disease (PD) and contributes significantly to a reduced quality of life in PD patients. We conducted a prospective longitudinal study of 89 mild PD patients over 18 months, measuring apathy symptoms at 6-monthly intervals using the Starkstein Apathy Scale, as well as measures of motor and non-motor symptoms, cognitive function, and functional disability at baseline. Mixed-effects models were used to characterise the in idual trajectories of apathy symptom severity, and linear regression with stepwise elimination procedure was used to select significant baseline predictors. Clinically significant levels of apathy were present in 42.7% of our s le at baseline, with symptom severity remaining relatively stable on average over the course of 18 months. Male gender, lower educational attainment, higher depression symptom severity, more severe functional disability, and the presence of dyskinesias at study entry predicted increasing apathy over the subsequent 18 months. Patients with these factors are at risk for progression of apathy, which may be prevented by treating depression and functional disability. Further studies are needed to address both the specific neurobiological pathways and psychosocial factors underpinning apathy in PD.
Publisher: Elsevier BV
Date: 2017
Publisher: Wiley
Date: 07-2014
Publisher: Wiley
Date: 14-06-2022
Abstract: The pericapsular nerve group (PENG) block was first described for analgesia of hip fracture in 2018. We hypothesised that the PENG block is safe and effective for patients with hip fracture when provided by emergency physicians and trainees in the ED. This was an observational study of routine care. Consecutive patients receiving regional anaesthesia for hip fracture at a single ED were prospectively enrolled. Pain scores were assessed prior to regional anaesthesia then at 15, 30 and 60 min after administration. Maximal reduction in pain scores within 60 min were assessed using the Visual Analogue Scale (at rest and on movement) or the Pain Assessment IN Advanced Dementia tool (at rest). Patients were followed for opioid use for 12 h after regional anaesthesia and adverse events over the duration of admission. There were 67 eligible patients during the enrolment period, with 52 (78%) prospectively enrolled. Thirty-three received femoral blocks (19 fascia iliaca compartment blocks, 14 femoral nerve blocks) and 19 received a PENG block. Inexperienced providers were able to successfully perform the PENG block. There was no difference in maximum pain score reduction between the groups. There was no difference in adverse effects between groups. Opioid use was similar between the groups. More patients were opioid-free after a PENG block. The present study demonstrated that the PENG block can be provided safely and effectively to patients with hip fracture in the ED. On the basis of this pilot study, a larger randomised controlled study should now be designed.
Publisher: Wiley
Date: 07-2014
Publisher: Oxford University Press (OUP)
Date: 11-08-2021
DOI: 10.1136/POSTGRADMEDJ-2020-138184
Abstract: Motor neuron disease (MND) is a neurodegenerative disorder leading to functional decline and death. Multidisciplinary MND clinics provide an integrated approach to management and facilitate discussion on advanced care directives (ACDs). The study objectives are to analyse (1) the prevalence of ACD in our MND clinic, (2) the relationship between ACD and patient demographics and (3) the relationship between ACD decision-making and variables such as NIV, PEG, hospital admissions and location of death. Using clinic records, all patients who attended the MND clinic in Liverpool Hospital between November 2014 and November 2019 were analysed. Data include MND subtypes, symptom onset to time of diagnosis, time of diagnosis to death, location and reason of death. ACD prevalence, non-invasive ventilation (NIV) and percutaneous endoscopic gastrostomy (PEG) requirements were analysed. There were 78 patients M:F=1:1. 44 (56%) patients were limb onset, 28 (36%) bulbar onset, 4 primary lateral sclerosis and 2 flail limb syndrome presentations. 27% patients completed ACDs, while 32% patients declined ACDs. Patients born in Australia or in a majority English-speaking country were more likely to complete ACDs compared to those born in a non-English-speaking country. There was no significant correlation between ACD completion and age, gender, MND subtype, symptom duration, NIV, PEG feeding, location of death. One-quarter of patients completed ACDs. ACDs did not correlate with patient age, gender, MND subtype and symptom duration or decision-making regarding NIV, PEG feeding or location of death. Further studies are needed to address factors influencing patients' decisions regarding ACDs.
Publisher: Elsevier BV
Date: 02-2016
DOI: 10.1016/J.PARKRELDIS.2015.12.001
Abstract: Depression and anxiety are common in Parkinson's disease (PD) and contribute significantly to a reduced quality of life in PD patients. Though they often co-exist, it is unclear whether depression and anxiety result from a shared pathological process. We studied the longitudinal course and determinants of depression and anxiety in PD in order to understand which factors contribute to the development of these symptoms. We conducted a prospective longitudinal study of 89 mild PD patients over 18 months, measuring depressive and anxiety symptoms at 6 monthly intervals using the Geriatric Depression Scale and Hospital Anxiety and Depression Scale--'Anxiety' subscale. Univariate and multivariate Generalised Estimating Equations were used to investigate the course of depression and anxiety and their association with demographic factors, motor measures, non-motor symptoms, and pharmacological factors. Depression and anxiety were co-morbid in 13.5% of the s le. Depressive symptoms remained relatively stable while anxiety symptoms improved over the course of 18 months. Severity of depressive symptoms was associated with female gender, motor fluctuations, apathy, and anxiety, while severity of anxiety was associated with older age, higher educational attainment, shorter disease duration, younger age of disease onset, and excessive daytime sleepiness. Although depression and anxiety are frequently co-morbid in PD, they were dissociable from each other. They had distinct trajectories and different longitudinal relationships with demographic, motor, and non-motor factors that were unique to each disorder.
Publisher: The Royal Society
Date: 2021
Abstract: COVID-19 is highly transmissible and containing outbreaks requires a rapid and effective response. Because infection may be spread by people who are pre-symptomatic or asymptomatic, substantial undetected transmission is likely to occur before clinical cases are diagnosed. Thus, when outbreaks occur there is a need to anticipate which populations and locations are at heightened risk of exposure. In this work, we evaluate the utility of aggregate human mobility data for estimating the geographical distribution of transmission risk. We present a simple procedure for producing spatial transmission risk assessments from near-real-time population mobility data. We validate our estimates against three well-documented COVID-19 outbreaks in Australia. Two of these were well-defined transmission clusters and one was a community transmission scenario. Our results indicate that mobility data can be a good predictor of geographical patterns of exposure risk from transmission centres, particularly in outbreaks involving workplaces or other environments associated with habitual travel patterns. For community transmission scenarios, our results demonstrate that mobility data add the most value to risk predictions when case counts are low and spatially clustered. Our method could assist health systems in the allocation of testing resources, and potentially guide the implementation of geographically targeted restrictions on movement and social interaction.
Publisher: Springer Science and Business Media LLC
Date: 26-07-2014
Publisher: Wiley
Date: 21-08-2015
DOI: 10.1111/ENE.12546
Abstract: Whilst there is evidence implicating small vessel cerebrovascular disease in the pathogenesis of Alzheimer's disease (AD), its specific contribution to the pathophysiology of AD remains unclear. The burden of small vessel cerebrovascular disease visualized as white matter hyperintensity (WMH) and its association with medial temporal atrophy (MTA) at different stages of AD was studied. One hundred and sixty-five cognitively normal (CN) community controls, 103 mild cognitive impairment (MCI) patients, 141 mild AD patients and 68 moderate-severe AD patients were studied. Clinical, cognitive and risk factor data were collected, and WMH and MTA were quantified by trained raters. The Jonckheere-Terpstra test for ordered alternatives was used to study the association between WMH and MTA in different stages of AD. The burden of total WMH increased significantly with increasing severity of AD, even after correcting for confounders. The proportion of CN, MCI, mild AD and moderate-severe AD subjects with severe burden of WMH was 6.7%, 9.7%, 28.4%, and 39.7%, respectively. A strong positive association between WMH severity and MTA was evident amongst MCI (P = 0.011) and mild AD (P = 0.003) subjects, but not in CN (P = 0.953) and moderate-severe AD subjects (P = 0.301). The burden of WMH increased significantly from the stage of CN to MCI to AD. The association between WMH and MTA was greatest at the stage of MCI and mild AD. This has implications on the strategy to slow the progression of AD, where measures to reduce WMH, including control of vascular risk factors, need to be optimized at the stage of MCI and mild AD.
Publisher: Wiley
Date: 07-2014
Publisher: Elsevier BV
Date: 11-2014
DOI: 10.1016/J.PARKRELDIS.2014.08.024
Abstract: Longitudinal neuroimaging studies could provide insights into pathophysiology of cognitive impairment in PD. We examined the role of hippoc al atrophy and cerebral white matter disease as risk factors for mild cognitive impairment and dementia in PD. Prospective longitudinal study of patients with mild PD in a tertiary neurology center. All subjects underwent baseline MRI brain and had baseline and 6 monthly cognitive evaluations. Cognitive impairment was diagnosed based on the Movement Disorder Society Criteria. The predictive role of hippoc al volume and white matter hyperintensity at baseline on progression of cognitive impairment was studied. 97 subjects with mean age 65.3 years, mean education of 10.3 years and mean Hoehn & Yahr of 1.9 were studied. Over 2 years, 16 subjects developed mild cognitive impairment and 8 subjects with mild cognitive impairment progressed to dementia. After adjusting for age and vascular risk factors, hippoc al volume was a significant predictor for mild cognitive impairment (OR 7.05, CI 1.5-34.1 p = 0.015) and dementia (OR 7.03, CI 2.39-25.2 p = 0.001). With Cox regression, hippoc al volume was a significant predictor for "time to cognitive impairment" (HR 7.67 CI 3.47-16.95, p < 0.001). Difference between survival curves based on volume of white matter hyperintensity in predicting "time to mild cognitive impairment" was significant (p = 0.0295). Hippoc al volume is a major factor predicting the development of mild cognitive impairment and dementia in PD. White matter hyperintensity also contributes to the longitudinal cognitive status in PD.
Location: United States of America
No related grants have been discovered for Aloysius Ng.