Yi Chao Foong

Dr. Yi Chao Foong


Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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27 March 2023 in Multiple Sclerosis and Related Disorders
Verified
Journal Article
Open access
YFYi Chao Foong
Yi Chao Foong
FBFrancesca Bridge
Francesca Bridge
DMDaniel Merlo
Daniel Merlo
MGMelissa Gresle
Melissa Gresle
CZChao Zhu
Chao Zhu
AWAnneke van der Walt
Anneke van der Walt
Current cognitive monitoring of people with multiple sclerosis (pwMS) is sporadic, resource intensive and insensitive for detection of real-world cognitive performance and decline. Smartphone applications may provide us with a more sensitive biomarker for cognitive decline that reflects real-world performance. The goal of this study was to perform a systematic review and qualitative synthesis of all current smartphone apps monitoring cognition in pwMS. A systematic search of five major online databases (PubMed/Medline, Scopus, Web of Science, Cumulative Index of Nursing and Allied Health Literature and IEEE Xplore) was performed in accordance with the Cochrane Handbook and Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. We included all studies with at least one measure of phone-based digital biomarkers for monitoring cognition in pwMS above the age of 18. Two authors independently screened the articles retrieved. Data on test-retest reliability, validity coefficients, feasibility and practice effects were extracted from the studies identified. Critical appraisal of the studies was performed using the National Institute of Health quality assessment tool for observational cohort and cross-sectional studies. 12 articles covering six smartphone apps were included in this review. All articles had a low risk of bias, though sample size calculation was rarely performed. Of the six apps, five used smartphone versions of the symbol digit modalities test. The final app examined keystroke features passively. Test-retest reliability ranged from good to excellent. Concurrent validity was demonstrated through moderate to strong correlation with neuropsychological tests and weak to moderate correlations with EDSS, radiological biomarkers and patient-reported outcomes. Mobile apps performed comparably, and in some cases outperformed established cognitive tests. Whilst reported acceptability was high, significant attrition rates were present in longitudinal cohorts. There were significant short and long-term practice effects. Overall, smartphone versions of the SDMT showed strong psychometric properties across multiple apps. Smartphone applications are reliable and valid biomarkers of real-world cognition in pwMS. Further longitudinal data would allow for a better understanding of their predictive and ecological validity.

26 June 2023 in Orphanet Journal of Rare Diseases
Verified
Journal Article
Open access
PDF file
FSFelicity Stringer
Felicity Stringer
YFYi Chao Foong
Yi Chao Foong
ATAlanna Tan
Alanna Tan
SHSarah Hayman
Sarah Hayman
JZJeffrey D. Zajac
Jeffrey D. Zajac
SASujith Ayyappan
Sujith Ayyappan
Background: Pituitary abscess (PA) is a rare condition and not well understood. We aimed to describe a case and perform a comprehensive systematic review to explore presenting symptoms, radiological findings, endocrine abnormalities and mortality. Aim: To identify presenting symptoms, radiological findings, endocrinological abnormalities and predictors of mortality for PA. Methods: We systematically reviewed the literature to identify all case reports of PA. Data regarding presentation, mortality, radiological findings, endocrinological abnormalities and treatment was extracted. Results: We identified 488 patients from 218 articles meeting the inclusion criteria. Mortality was 5.1%, with days to presentation (OR 1.0005, 95% CI 1.0001–1.0008, p < 0.01) being the only identified independent predictor of mortality. Mortality rates have decreased over time, with cases published prior to 2000 having higher mortality rates (OR 6.92, 95% CI 2.80–17.90, p < 0.001). The most common symptom was headache (76.2%), followed by visual field defects (47.3%). Classical signs of infection were only present in 43%. The most common imaging feature on magnetic resonance imaging (MRI) was high T2 and low T1 signal of the pituitary gland with peripheral contrast enhancement. Over half (54.8%) were culture negative, with the most common bacterial organism being staphylococcus aureus (7.8%) and fungal organism being aspergillus (8.8%). The most common endocrine abnormality was hypopituitarism (41.1%), followed by diabetes insipidus (24.8%). Whilst symptoms resolved in most patients, persistent endocrine abnormalities were present in over half of patients (61.0%). Conclusion: PA is associated with significant mortality, with delayed presentation increasing risk of mortality. Ongoing endocrinological abnormalities are common. Given the non-specific clinical presentation, the appearance of high T2, low T1 and peripheral contrast enhancement of the pituitary on MRI should prompt consideration of this rare disease.

24 December 2024 in Neurology
Verified
Journal Article
Closed access
PSPakeeran Siriratnam
Pakeeran Siriratnam
SHSaif Huda
Saif Huda
AWAnneke Van der Walt
Anneke Van der Walt
PSPaul G. Sanfilippo
Paul G. Sanfilippo
SSSifat Sharmin
Sifat Sharmin
FMFor Msbase
For Msbase
In aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder (AQP4-IgG NMOSD), disability accrual is mostly attributed to relapses. This study aimed to assess the prevalence of progression independent of relapse activity (PIRA) and relapse-associated worsening (RAW) in AQP4-IgG NMOSD. This was a retrospective cohort study of patients with AQP4-IgG NMOSD enrolled in the MSBase international data registry. Patients required a minimum of 3 recorded Expanded Disability Status Scale (EDSS) scores: baseline, event, and a 6-month confirmation score. Presence and absence of relapses between the baseline and event EDSS scores determined RAW and PIRA, respectively. Descriptive statistics were used to present the results. A total of 181 patients followed for a median of 4.5 years (Q1 1.7, Q3 7.8) were included. Most patients were female (88.4%), and the median age at disease onset was 38.1 years. Overall, 4 patients (2.2%) developed 5 incidences of PIRA and 13 patients developed RAW (7.2%). This multicenter study highlights that PIRA is very rare in AQP4-IgG NMOSD. Limitations of this study include the sole focus of overall EDSS to measure disability, lack of requirement for a second EDSS score to confirm baseline EDSS, and the absence of magnetic resonance imaging information for all patients.

7 March 2024 in Journal of Neurology, Neurosurgery & Psychiatry
Verified
Journal Article
Closed access
PDF file
YFYi Chao Foong
Yi Chao Foong
DMDaniel Merlo
Daniel Merlo
MGMelissa Gresle
Melissa Gresle
KBKatherine Buzzard
Katherine Buzzard
MZMichael Zhong
Michael Zhong
CZChao Zhu
Chao Zhu
Background Ongoing controversy exists regarding optimal management of disease modifying therapy (DMT) in older people with multiple sclerosis (pwMS). There is concern that the lower relapse rate, combined with a higher risk of DMT-related infections and side effects, may alter the risk-benefit balance in older pwMS. Given the lack of pwMS above age 60 in randomised controlled trials, the comparative efficacy of high-efficacy DMTs such as ocrelizumab has not been shown in older pwMS. We aimed to evaluate the comparative effectiveness of ocrelizumab, a high-efficacy DMT, versus interferon/glatiramer acetate (IFN/GA) in pwMS over the age of 60. Methods Using data from MSBase registry, this multicentre cohort study included pwMS above 60 who switched to or started on ocrelizumab or IFN/GA. We analysed relapse and disability outcomes after balancing covariates using an inverse probability treatment weighting (IPTW) method. Propensity scores were obtained based on age, country, disease duration, sex, baseline Expanded Disability Status Scale, prior relapses (all-time, 12 months and 24 months) and prior DMT exposure (overall number and high-efficacy DMTs). After weighting, all covariates were balanced. Primary outcomes were time to first relapse and annualised relapse rate (ARR). Secondary outcomes were 6-month confirmed disability progression (CDP) and confirmed disability improvement (CDI). Results A total of 248 participants received ocrelizumab, while 427 received IFN/GA. The IPTW-weighted ARR for ocrelizumab was 0.01 and 0.08 for IFN/GA. The IPTW-weighted ARR ratio was 0.15 (95% CI 0.06 to 0.33, p<0.001) for ocrelizumab compared with IFN/GA. On IPTW-weighted Cox regression models, HR for time to first relapse was 0.13 (95% CI 0.05 to 0.26, p<0.001). The hazard of first relapse was significantly reduced in ocrelizumab users after 5 months compared with IFN/GA users. However, the two groups did not differ in CDP or CDI over 3.57 years. Conclusion In older pwMS, ocrelizumab effectively reduced relapses compared with IFN/GA. Overall relapse activity was low. This study adds valuable real-world data for informed DMT decision making with older pwMS. Our study also confirms that there is a treatment benefit in older people with MS, given the existence of a clear differential treatment effect between ocrelizumab and IFN/GA in the over 60 age group.

24 August 2023 in European Journal of Neurology
Verified
Journal Article
Open access
YFYi Chao Foong
Yi Chao Foong
DMDaniel Merlo
Daniel Merlo
MGMelissa Gresle
Melissa Gresle
CZChao Zhu
Chao Zhu
KBKatherine Buzzard
Katherine Buzzard
AWAnneke Van der Walt
Anneke Van der Walt
Background and purpose: The validity, reliability, and longitudinal performance of the Patient‐Determined Disease Steps (PDDS) scale is unknown in people with multiple sclerosis (MS) with mild to moderate disability. We aimed to examine the psychometric properties and longitudinal performance of the PDDS.Methods: We included relapsing–remitting MS patients with an Expanded Disability Status Scale (EDSS) score of less than 4. Validity and test–retest reliability was examined. Longitudinal data were analysed with mixed‐effect modelling and Cohen's kappa for concordance in confirmed disability progression (CDP).Results: We recruited a total of 1093 participants, of whom 904 had complete baseline data. The baseline correlation between PDDS and EDSS was weak (ρ = 0.45, p < 0.001). PDDS had stronger correlations with patient‐reported outcomes (PROs). Conversely, EDSS had stronger correlations with age, disease duration, Kurtzke's functional systems and processing speed test. PDDS test–retest reliability was good to excellent (concordance correlation coefficient = 0.73–0.89). Longitudinally, PDDS was associated with EDSS, age and depression. A higher EDSS score was associated with greater PDSS progression. The magnitude of these associations was small. There was no concordance in CDP as assessed by PDDS and EDSS.Conclusion: The PDDS has greater correlation with other PROs but less correlation with other MS‐related outcome measures compared to the EDSS. There was little correlation between PDDS and EDSS longitudinally. Our findings suggest that the PDDS scale is not interchangeable with the EDSS.

25 February 2025 in Annals of Clinical and Translational Neurology
Verified
Journal Article
Open access
YFYi Chao Foong
Yi Chao Foong
DMDaniel Merlo
Daniel Merlo
MGMelissa Gresle
Melissa Gresle
CZChao Zhu
Chao Zhu
KBKatherine Buzzard
Katherine Buzzard
AWAnneke Van der Walt
Anneke Van der Walt
Background: Cognitive impairment is one of the most common and debilitating symptoms of relapsing–remitting multiple sclerosis (RRMS). Digital cognitive biomarkers require less time and resources and are rapidly gaining popularity in clinical settings. We examined the longitudinal trajectory of the iPad‐based Processing Speed Test (PST) and predictors of PST scores.Methods: We prospectively enrolled RRMS patients between 2017 and 2021 across six Australian MS centres. Longitudinal data was analysed with mixed effect modelling and latent class mixed models. We then examined whether latent class group membership predicted confirmed decrease in correct PST responses.Results: We recruited a total of 1093 participants, of which 724 had complete baseline data with a median follow up duration of 2 years. At a population level, PST trajectory was stable. A small practice effect was present up to the 4th visit. Age, baseline disability, T2 lesion volume, male sex and depression were associated with lower correct PST responses, whilst years of education and full/part‐time employment were associated with more correct PST responses.We identified four latent class trajectories of PST. The worst latent class was typified by low baseline PST and lack of a practice effect. Being in the worst latent class was associated with a greater hazard of time to sustained 5% decrease in PST (HR 2.84, 95% CI 1.16–6.94, p = 0.02).Conclusion: Worse baseline cognitive performance and lack of a practice effect predicted future cognitive decline in RRMS.