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Lee TC, Leung WC, Ho C, Chiu MW, Leung IY, Wong YK, Roxanna LK, Sum CH, Lui DT, Cheung RT, Leung GK, Chan KH, Teo KC, Lau KK. Association of LDL-cholesterol <1.8 mmol/L and statin use with the recurrence of intracerebral hemorrhage. Int J Stroke 2024; 19:695-704. [PMID: 38429252 DOI: 10.1177/17474930241239523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2024]
Abstract
BACKGROUND Recent intensive low-density lipoprotein cholesterol (LDL-C) lowering trials, including FOURIER, ODYSSEY OUTCOMES, and Treat Stroke to Target (TST) trials, have mostly refuted the concern surrounding statin use, LDL-C lowering, and intracerebral hemorrhage (ICH) risk. However, the results from these trials may not be fully applied to ICH survivors, as the populations studied were mainly patients without prior ICH, in whom the inherent ICH risk is more than 10 times lower than that of ICH survivors. Although available literature on statin use after ICH has demonstrated no excess risk of recurrent ICH, other potential factors that may modify ICH risk, especially hypertension control and ICH etiology, have not generally been considered. Notably, data on LDL-C levels following ICH are lacking. AIMS We aim to investigate the association between LDL-C levels and statin use with ICH risk among ICH survivors, and to determine whether the risk differed with patients' characteristics, especially ICH etiology. METHODS Follow-up data of consecutive spontaneous ICH survivors enrolled in the University of Hong Kong prospective stroke registry from 2011 to 2019 were retrospectively analyzed. ICH etiology was classified as cerebral amyloid angiopathy (CAA) using the modified Boston criteria or hypertensive arteriopathy, while the mean follow-up LDL-C value was categorized as <1.8 or ⩾1.8 mmol/L. The primary endpoint was recurrent ICH. The association of LDL-C level and statin use with recurrent ICH was determined using multivariable Cox regression. Pre-specified subgroup analyses were performed, including based on ICH etiology and statin prescription. Follow-up blood pressure was included in all the regression models. RESULTS In 502 ICH survivors (mean age = 64.2 ± 13.5 years, mean follow-up LDL-C = 2.2 ± 0.6 mmol/L, 28% with LDL-C <1.8 mmol/L), 44 had ICH recurrence during a mean follow-up of 5.9 ± 2.8 years. Statin use after ICH was not associated with recurrent ICH (adjusted hazard ratio (AHR) = 1.07, 95% confidence interval (CI) = 0.57-2.00). The risk of ICH recurrence was increased for follow-up LDL-C <1.8 mmol/L (AHR = 1.99, 95% CI = 1.06-3.73). This association was predominantly observed in ICH attributable to CAA (AHR = 2.52, 95% CI = 1.06-5.99) and non-statin users (AHR = 2.91, 95% CI = 1.08-7.86). CONCLUSION The association between post-ICH LDL-C <1.8 mmol/L and recurrent ICH was predominantly observed in CAA patients and those with intrinsically low LDL-C (non-statin users). While statins can be safely prescribed in ICH survivors, LDL-C targets should be individualized and caution must be exercised in CAA patients.
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Chan YH, Zhao JV, Au Yeung SL, Wong YK, Au KW, Xu A, Lam TH, Cheung BMY, Lam KSL, Tse HF. Early Renal Dysfunction in Middle-Aged Adults Predicts Fatal and Nonfatal Cardiovascular Events. J Am Coll Cardiol 2024; 83:2711-2713. [PMID: 38897681 DOI: 10.1016/j.jacc.2024.04.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 04/15/2024] [Accepted: 04/16/2024] [Indexed: 06/21/2024]
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Wang X, Sin CF, Teo KC, Leung WCY, Wong YK, Liu RKC, Fok JW, Ip BY, Kwan HH, Lee TC, Sheng B, Yip EKK, Yap DYH, Luo H, Lau KK. Impact of renal function variability on long-term prognosis in ischemic stroke patients with atrial fibrillation. Front Neurol 2024; 15:1294022. [PMID: 38711560 PMCID: PMC11071668 DOI: 10.3389/fneur.2024.1294022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 03/25/2024] [Indexed: 05/08/2024] Open
Abstract
Background Although renal dysfunction is associated with adverse clinical outcomes in patients with atrial fibrillation (AF) following stroke, the impact of renal function variability is unclear. Aim This study aimed to assess the association between renal function variability and various adverse clinical outcomes in patients with transient ischemic attack (TIA)/ischemic stroke and atrial fibrillation (AF). Methods We conducted a population-based study and retrospectively identified patients hospitalized with a diagnosis of TIA/ischemic stroke and AF during 2016-2020 using the Clinical Data Analysis and Reporting System of Hong Kong. Serial serum creatinine tested upon the onset of TIA/ischemic stroke and during their subsequent follow-up was collected. Renal function variability was calculated using the coefficient of variation of the estimated glomerular filtration rate (eGFR). Clinical endpoints that occurred during the study period were captured and included ischemic stroke/systemic embolism, intracerebral hemorrhage (ICH), total bleeding, major adverse cardiovascular events (MACE), cardiovascular, non-cardiovascular, and all-cause mortality. Competing risk regression and Cox proportional hazard regression models were used to assess the associations of renal function variability with the outcomes of interest. Results A total of 3,809 patients (mean age 80 ± 10 years, 43% men) who satisfied the inclusion and exclusion criteria were followed up for a mean of 2.5 ± 1.5 years (9,523 patient-years). The mean eGFR was 66 ± 22 mL/min/1.73 m2 at baseline, and the median number of renal function tests per patient during the follow-up period was 20 (interquartile range 11-35). After accounting for potential confounders, a greater eGFR variability was associated with increased risks of recurrent ischemic stroke/systemic embolism [fully adjusted subdistribution hazard ratio 1.11, 95% confidence interval (CI) 1.03-1.20], ICH (1.17, 1.01-1.36), total bleeding (1.13, 1.06-1.21), MACE (1.22, 1.15-1.30), cardiovascular (1.49, 1.32-1.69), non-cardiovascular (1.43, 1.35-1.52), and all-cause mortality (fully adjusted hazard ratio 1.44, 1.39-1.50). Conclusion Visit-to-visit renal function variability is independently associated with adverse clinical outcomes in TIA/ischemic stroke patients with AF. Further large-scale studies are needed to validate our results.
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Ho I, Wong CK, Wong YK, Lam TH, Sze-Him Leung I, Lin M, Tak-Wai Lui D, Kwok WC, Tam CC, Chan YH, Chan EW, Tse HF. Aromatase Inhibitor Therapy Increases the Risk of New-Onset Atrial Fibrillation in Patients With Breast Cancer. JACC. ASIA 2024; 4:150-160. [PMID: 38371283 PMCID: PMC10866735 DOI: 10.1016/j.jacasi.2023.09.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 09/19/2023] [Accepted: 09/20/2023] [Indexed: 02/20/2024]
Abstract
Background Previous studies suggest that aromatase inhibitors (AIs) increase the risk of adverse cardiovascular events and cardiac arrhythmias in patients with breast cancer, but it is unclear whether AIs also increase the risk of new-onset atrial fibrillation (AF). Objectives The purpose of this study was to investigate whether the use of AIs was associated with an increased risk of new-onset AF in patients with breast cancer. Methods We performed a retrospective analysis involving 5,707 patients with breast cancer (mean age 63.9 ± 11.2 years and 99.9% women) who received adjunctive hormone therapy with an AI (AI group, n = 4,878) or tamoxifen (tamoxifen group, n = 829) in Hong Kong between January 1, 1999, and December 31, 2020. After propensity score matching, there were 1,658 and 829 patients with balanced characteristics in the AI group and tamoxifen group, respectively. Results After 8,863 patient-years of follow-up, patients who were prescribed AI had a trend toward more new-onset arrhythmias compared with those prescribed tamoxifen (0.62 vs 0.30 per 100 patient-years; crude HR: 2.05; P = 0.053). The difference in arrhythmic risk was mainly driven by a higher incidence rate of new-onset AF in the AI group (0.59 vs 0.27 per 100 patient-years; crude HR: 2.18; P = 0.046). The use of AIs was confirmed to be an independent risk factor for new-onset AF on multivariate analysis (adjusted HR: 2.75; P = 0.01). Conclusions Among breast cancer patients prescribed adjunctive hormonal therapy, AI was associated with an increased risk of new-onset AF. Regular surveillance for new-onset AF should be considered in breast cancer patients treated with an AI.
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Teo KC, Fong SM, Leung WCY, Leung IYH, Wong YK, Choi OMY, Yam KK, Lo RCN, Cheung RTF, Ho SL, Tsang ACO, Leung GKK, Chan KH, Lau KK. Location-Specific Hematoma Volume Cutoff and Clinical Outcomes in Intracerebral Hemorrhage. Stroke 2023; 54:1548-1557. [PMID: 37216445 DOI: 10.1161/strokeaha.122.041246] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 03/17/2023] [Indexed: 05/24/2023]
Abstract
BACKGROUND Major intracerebral hemorrhage (ICH) trials have largely been unable to demonstrate therapeutic benefit in improving functional outcomes. This may be partly due to the heterogeneity of ICH outcomes based on their location, where a small strategic ICH could be debilitating, thus confounding therapeutic effects. We aimed to determine the ideal hematoma volume cutoff for different ICH locations in predicting ICH outcomes. METHODS We retrospectively analyzed consecutive ICH patients enrolled in the University of Hong Kong prospective stroke registry from January 2011 to December 2018. Patients with premorbid modified Rankin Scale score >2 or who underwent neurosurgical intervention were excluded. ICH volume cutoff, sensitivity, and specificity in predicting respective 6-month neurological outcomes (good [modified Rankin Scale score 0-2], poor [modified Rankin Scale score 4-6], and mortality) for specific ICH locations were determined using receiver operating characteristic curves. Separate multivariate logistic regression models were also conducted for each location-specific volume cutoff to determine whether these cutoffs were independently associated with respective outcomes. RESULTS Among 533 ICHs, the volume cutoff for good outcome according to ICH location was 40.5 mL for lobar, 32.5 mL for putamen/external capsule, 5.5 mL for internal capsule/globus pallidus, 6.5 mL for thalamus, 17 mL for cerebellum, and 3 mL for brainstem. ICH smaller than the cutoff for all supratentorial sites had higher odds of good outcomes (all P<0.05). Volumes exceeding 48 mL for lobar, 41 mL for putamen/external capsule, 6 mL for internal capsule/globus pallidus, 9.5 mL for thalamus, 22 mL for cerebellum, and 7.5 mL for brainstem were at greater risk of poor outcomes (all P<0.05). Mortality risks were significantly higher for volumes that exceeded 89.5 mL for lobar, 42 mL for putamen/external capsule, and 21 mL for internal capsule/globus pallidus (all P<0.001). All receiver operating characteristic models for location-specific cutoffs had good discriminant values (area under the curve >0.8), except in predicting good outcome for cerebellum. CONCLUSIONS ICH outcomes differed with location-specific hematoma size. Location-specific volume cutoff should be considered in patient selection for ICH trials.
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Teo KC, Keins S, Abramson JR, Leung WCY, Leung IYH, Wong YK, Yeung C, Kourkoulis C, Warren AD, Chan KH, Cheung RTF, Ho SL, Gurol ME, Viswanathan A, Greenberg SM, Anderson CD, Lau KK, Rosand J, Biffi A. Blood Pressure Control Targets and Risk of Cardiovascular and Cerebrovascular Events After Intracerebral Hemorrhage. Stroke 2023; 54:78-86. [PMID: 36321455 DOI: 10.1161/strokeaha.122.039709] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND Intracerebral hemorrhage (ICH) survivors are at high risk for recurrent stroke and cardiovascular events. Blood pressure (BP) control represents the most potent intervention to lower these risks, but optimal treatment targets in this patient population remain unknown. We sought to determine whether survivors of ICH achieving more intensive BP control than current guideline recommendations (systolic BP <130 mmHg and diastolic BP <80 mmHg) were at lower risk of major adverse cardiovascular and cerebrovascular events and mortality. METHODS We analyzed data for 1828 survivors of spontaneous ICH from 2 cohort studies. Follow-up BP measurements were recorded 3 and 6 months after ICH, and every 6 months thereafter. Outcomes of interest were major adverse cardiovascular and cerebrovascular events (recurrent ICH, incident ischemic stroke, myocardial infarction), vascular mortality (defined as mortality attributed to recurrent ICH, ischemic stroke, or myocardial infarction), and all-cause mortality. RESULTS During a median follow-up of 46.2 months, we observed 166 recurrent ICH, 68 ischemic strokes, 69 myocardial infarction, and 429 deaths. Compared with survivors of ICH with systolic BP 120 to 129 mmHg, participants who achieved systolic BP <120 mmHg displayed reduced risk of recurrent ICH (adjusted hazard ratio [AHR], 0.74 [95% CI, 0.59-0.94]) and major adverse cardiovascular and cerebrovascular events (AHR, 0.69 [95% CI, 0.53-0.92]). All-cause mortality (AHR, 0.76 [95% CI, 0.57-1.03]) and vascular mortality (AHR, 0.68 [95% CI, 0.45-1.01]) did not differ significantly. Among participants aged >75 years or with modified Rankin Scale score 4 to 5, systolic BP <120 mmHg was associated with increased all-cause mortality (AHR, 1.38 [95% CI, 1.02-1.85] and AHR, 1.36 [95% CI, 1.03-1.78], respectively), but not vascular mortality. We found no differences in outcome rates between survivors of ICH with diastolic BP <70 versus 70 to 79 mmHg. CONCLUSIONS Targeting systolic BP <120 mmHg in select groups of survivors of ICH could result in decreased major adverse cardiovascular and cerebrovascular events risk without increasing mortality. Our findings warrant investigation in dedicated randomized controlled trials.
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Tse HF, Teo WS, Siu CW, Chao TF, Park HW, Shimizu W, Wong YK, Lip GYH. Prognosis and treatment of atrial fibrillation in Asian cities: 1-year review of the Asia-Pacific Heart Rhythm Society Atrial Fibrillation Registry. Europace 2022; 24:1889-1898. [PMID: 35025986 DOI: 10.1093/europace/euab327] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Accepted: 12/24/2021] [Indexed: 12/16/2022] Open
Abstract
AIMS The aim of this study is to describe the implementation of the current guidance for stroke prevention and treatment option in atrial fibrillation (AF) and to evaluate mortality and morbidity in relation to therapeutic decisions, including persistence with treatment at 1 year in Asia-Pacific regions. METHODS AND RESULTS We recruited 4664 patients consecutive in- and outpatients with AF who presented to cardiologists in five countries under the Asia-Pacific Heart Rhythm Society (APHRS) in whom 1-year follow-up was completed for 4003 (65.5% male; mean age 68.5 years). Oral anticoagulant (OAC) use remained high, 77% at follow-up, including 17% prescribed a vitamin K antagonist (VKA) and 60% a non-VKA oral anticoagulant (NOAC). At 1-year follow-up, 93% and 88% remained on a VKA or NOAC, respectively. With good adherence to OAC therapy, 1-year mortality was only 2.7%. Most deaths were non-cardiovascular (72.3%) and the 1-year incidence of stroke/transient ischaemic events (TIA) was low (<1%). Hospital readmissions were common for non-cardiovascular cases and atrial tachyarrhythmias. On multivariate analysis, independent baseline predictors of mortality and/or stroke/TIA/peripheral embolism were age, previous heart failure for >12 months, and malignancy. Independent predictors of mortality were age, chronic obstructive pulmonary disease, malignancy, and diuretic use. AF as a primary presentation was predictive of lower mortality and/or stroke/TIA/peripheral embolism as well as mortality. CONCLUSION In this 1-year analysis of the APHRS-AF registry, overall OAC use and persistence were high and were associated with low 1-year cardiovascular mortality and morbidity, but mortality and morbidity related to non-cardiovascular causes were high in AF patients, particularly from malignancy and pneumonia.
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Lee MC, Wong YK, Lee ACW, Fung HS, Chiang JB, Kwok CH, Chiu LF. Single-centre Initial Experience of Transradial Access for Abdominal Interventional Radiology. HONG KONG JOURNAL OF RADIOLOGY 2022. [DOI: 10.12809/hkjr2217400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Tam CCF, Chan YH, Wong YK, Li Z, Zhu X, Su KJ, Ganguly A, Hwa K, Ling XB, Tse HF. Multi-Omics Signatures Link to Ticagrelor Effects on Vascular Function in Patients With Acute Coronary Syndrome. Arterioscler Thromb Vasc Biol 2022; 42:789-798. [PMID: 35387483 DOI: 10.1161/atvbaha.121.317513] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND Long-term antiplatelet agents including the potent P2Y12 antagonist ticagrelor are indicated in patients with a previous history of acute coronary syndrome. We sought to compare the effect of ticagrelor with that of aspirin monotherapy on vascular endothelial function in patients with prior acute coronary syndrome. METHODS This was a prospective, single center, parallel group, investigator-blinded randomized controlled trial. We randomized 200 patients on long-term aspirin monotherapy with prior acute coronary syndrome in a 1:1 fashion to receive ticagrelor 60 mg BD (n=100) or aspirin 100 mg OD (n=100). The primary end point was change from baseline in brachial artery flow-mediated dilation at 12 weeks. Secondary end points were changes to platelet activation marker (CD41_62p) and endothelial progenitor cell (CD34/133) count measured by flow cytometry, plasma level of adenosine, IL-6 (interleukin-6) and EGF (epidermal growth factor), and multi-omics profiling at 12 weeks. RESULTS After 12 weeks, brachial flow-mediated dilation was significantly increased in the ticagrelor group compared with the aspirin group (ticagrelor: 3.48±3.48% versus aspirin: -1.26±2.85%, treatment effect 4.73 [95% CI, 3.85-5.62], P<0.001). Nevertheless ticagrelor treatment for 12 weeks had no significant effect on platelet activation markers, circulating endothelial progenitor cell count or plasma level of adenosine, IL-6, and EGF (all P>0.05). Multi-omics pathway assessment revealed that changes in the metabolism and biosynthesis of amino acids (cysteine and methionine metabolism; phenylalanine, tyrosine, and tryptophan biosynthesis) and phospholipids (glycerophosphoethanolamines and glycerophosphoserines) were associated with improved brachial artery flow-mediated dilation in the ticagrelor group. CONCLUSIONS In patients with prior acute coronary syndrome, ticagrelor 60 mg BD monotherapy significantly improved brachial flow-mediated dilation compared with aspirin monotherapy and was associated with significant changes in metabolomic and lipidomic signatures. REGISTRATION URL: https://www. CLINICALTRIALS gov; Unique identifier: NCT03881943.
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Wong YK, Tse HF. Circulating Biomarkers for Cardiovascular Disease Risk Prediction in Patients With Cardiovascular Disease. Front Cardiovasc Med 2021; 8:713191. [PMID: 34660715 PMCID: PMC8517145 DOI: 10.3389/fcvm.2021.713191] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Accepted: 09/08/2021] [Indexed: 12/23/2022] Open
Abstract
Cardiovascular disease (CVD) is the leading cause of death globally. Risk assessment is crucial for identifying at-risk individuals who require immediate attention as well as to guide the intensity of medical therapy to reduce subsequent risk of CVD. In the past decade, many risk prediction models have been proposed to estimate the risk of developing CVD. However, in patients with a history of CVD, the current models that based on traditional risk factors provide limited power in predicting recurrent cardiovascular events. Several biomarkers from different pathophysiological pathways have been identified to predict cardiovascular events, and the incorporation of biomarkers into risk assessment may contribute to enhance risk stratification in secondary prevention. This review focuses on biomarkers related to cardiovascular and metabolic diseases, including B-type natriuretic peptide, high-sensitivity cardiac troponin I, adiponectin, adipocyte fatty acid-binding protein, heart-type fatty acid-binding protein, lipocalin-2, fibroblast growth factor 19 and 21, retinol-binding protein 4, plasminogen activator inhibitor-1, 25-hydroxyvitamin D, and proprotein convertase subtilisin/kexin type 9, and discusses the potential utility of these biomarkers in cardiovascular risk prediction among patients with CVD. Many of these biomarkers have shown promise in improving risk prediction of CVD. Further research is needed to assess the validity of biomarker and whether the strategy for incorporating biomarker into clinical practice may help to optimize decision-making and therapeutic management.
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Chan YH, Schooling CM, Zhao J, Au Yeung SL, Hai JJ, Thomas GN, Cheng KK, Jiang CQ, Wong YK, Au KW, Tang CS, Cheung CYY, Xu A, Sham PC, Lam TH, Lam KSL, Tse HF. Mendelian Randomization Focused Analysis of Vitamin D on the Secondary Prevention of Ischemic Stroke. Stroke 2021; 52:3926-3937. [PMID: 34565175 DOI: 10.1161/strokeaha.120.032634] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND AND PURPOSE Experimental studies showed vitamin D (Vit-D) could promote vascular regeneration and repair. Prior randomized studies had focused mainly on primary prevention. Whether Vit-D protects against ischemic stroke and myocardial infarction recurrence among subjects with prior ischemic insults was unknown. Here, we dissected through Mendelian randomization any effect of Vit-D on the secondary prevention of recurrent ischemic stroke and myocardial infarction. METHODS Based on a genetic risk score for Vit-D constructed from a derivation cohort sample (n=5331, 45% Vit-D deficient, 89% genotyped) via high-throughput exome-chip screening of 12 prior genome-wide association study-identified genetic variants of Vit-D mechanistic pathways (rs2060793, rs4588, and rs7041; F statistic, 73; P<0.001), we performed a focused analysis on prospective recurrence of myocardial infarction (MI) and ischemic stroke in an independent subsample with established ischemic disease (n=441, all with prior first ischemic event; follow-up duration, 41.6±14.3 years) under a 2-sample, individual-data, prospective Mendelian randomization approach. RESULTS In the ischemic disease subsample, 11.1% (n=49/441) had developed recurrent ischemic stroke or MI and 13.3% (n=58/441) had developed recurrent or de novo ischemic stroke/MI. Kaplan-Meier analyses showed that genetic risk score predicted improved event-free survival from recurrent ischemic stroke or MI (log-rank, 13.0; P=0.001). Cox regression revealed that genetic risk score independently predicted reduced risk of recurrent ischemic stroke or MI combined (hazards ratio, 0.62 [95% CI, 0.48-0.81]; P<0.001), after adjusted for potential confounders. Mendelian randomization supported that Vit-D is causally protective against the primary end points of recurrent ischemic stroke or MI (Wald estimate: odds ratio, 0.55 [95% CI, 0.35-0.81]) and any recurrent or de novo ischemic stroke/MI (odds ratio, 0.64 [95% CI, 0.42-0.91]) and recurrent MI alone (odds ratio, 0.52 [95% CI, 0.30-0.81]). CONCLUSIONS Genetically predicted lowering in Vit-D level is causal for the recurrence of ischemic vascular events in persons with prior ischemic stroke or MI.
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Lau KK, Chua BJ, Ng A, Leung IYH, Wong YK, Chan AHY, Chiu YK, Chu AXW, Leung WCY, Tsang ACO, Teo KC, Mak HKF. Low-Density Lipoprotein Cholesterol and Risk of Recurrent Vascular Events in Chinese Patients With Ischemic Stroke With and Without Significant Atherosclerosis. J Am Heart Assoc 2021; 10:e021855. [PMID: 34369170 PMCID: PMC8475056 DOI: 10.1161/jaha.121.021855] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Background Recent trials have shown that low‐density lipoprotein cholesterol (LDL‐C) <1.80 mmol/L (<70 mg/dL) is associated with a reduced risk of major adverse cardiovascular events in White patients with ischemic stroke with atherosclerosis. However, it remains uncertain whether the findings can be generalized to Asian patients, or that similar LDL‐C targets should be adopted in patients with stroke without significant atherosclerosis. Methods and Results We performed a prospective cohort study and recruited consecutive Chinese patients with ischemic stroke with magnetic resonance angiography of the intra‐ and cervicocranial arteries performed at the University of Hong Kong between 2008 and 2014. Serial postevent LDL‐C measurements were obtained. Risk of major adverse cardiovascular events in patients with mean postevent LDL‐C <1.80 versus ≥1.80 mmol/L, stratified by presence or absence of significant (≥50%) large‐artery disease (LAD) and by ischemic stroke subtypes, were compared. Nine hundred four patients (mean age, 69±12 years; 60% men) were followed up for a mean 6.5±2.4 years (mean, 9±5 LDL‐C readings per patient). Regardless of LAD status, patients with a mean postevent LDL‐C <1.80 mmol/L were associated with a lower risk of major adverse cardiovascular events (with significant LAD: multivariable‐adjusted subdistribution hazard ratio, 0.65; 95% CI, 0.42–0.99; without significant LAD: subdistribution hazard ratio, 0.53; 95% CI, 0.32–0.88) (both P<0.05). Similar findings were noted in patients with ischemic stroke attributable to large‐artery atherosclerosis (subdistribution hazard ratio, 0.48; 95% CI, 0.28–0.84) and in patients with other ischemic stroke subtypes (subdistribution hazard ratio, 0.64; 95% CI, 0.43–0.95) (both P<0.05). Conclusions A mean LDL‐C <1.80 mmol/L was associated with a lower risk of major adverse cardiovascular events in Chinese patients with ischemic stroke with and without significant LAD. Further randomized trials to determine the optimal LDL‐C cutoff in stroke patients without significant atherosclerosis are warranted.
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Wong YK, Chan YH, Hai JSH, Lau KK, Tse HF. Predictive value of visit-to-visit blood pressure variability for cardiovascular events in patients with coronary artery disease with and without diabetes mellitus. Cardiovasc Diabetol 2021; 20:88. [PMID: 33894788 PMCID: PMC8070286 DOI: 10.1186/s12933-021-01280-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 04/15/2021] [Indexed: 12/26/2022] Open
Abstract
Background High blood pressure is a major risk factor for cardiovascular disease. Visit-to-visit blood pressure variability (BPV) has recently been shown to predict cardiovascular outcomes. We investigated the predictive value of BPV for major adverse cardiovascular events (MACE) among patients with coronary artery disease (CAD), with and without type 2 diabetes mellitus (T2DM). Methods Patients with stable CAD were enrolled and monitored for new MACE. Visit-to-visit BPV was defined as the coefficient of variation (CV) of systolic and diastolic BP across clinic visits. Multivariable logistic regression analysis was performed to evaluate the association of BPV with MACE. Area under the receiver operating characteristic curve (AUC) was used to assess its predictive ability. Results Among 1140 Chinese patients with stable CAD, 192 (17%) experienced a new MACE. In multivariable analyses, the risk of MACE was significantly associated with CV of systolic BP (odds ratio [OR] for highest versus lowest quartile, 3.30; 95% CI 1.97–5.54), and diastolic BP (OR for highest versus lowest quartile, 2.39; 95% CI 1.39–4.11), after adjustment for variables of the risk factor model (age, gender, T2DM, hypertension, antihypertensive agents, number of BP measurements) and mean BP. The risk factor model had an AUC of 0.70 for prediction of MACE. Adding systolic/diastolic CV into the risk factor model with mean BP significantly increased the AUC to 0.73/0.72 (P = 0.002/0.007). In subgroup analyses, higher CV of systolic BP remained significantly associated with an increased risk for MACE in patients with and without T2DM, whereas the association of CV of diastolic BP with MACE was observed only in those without T2DM. Conclusions Visit-to-visit variability of systolic BP and of diastolic BP was an independent predictor of new MACE and provided incremental prognostic value beyond mean BP and conventional risk factors in patients with stable CAD. The association of BPV in CAD patients without T2DM with subsequent risk for MACE was stronger than in those with T2DM. Supplementary Information The online version contains supplementary material available at 10.1186/s12933-021-01280-z.
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Kuo MCC, Au KT, Li YS, Siu KC, Wong YK, Chiu ATS, Yeung K. Validation of the Chinese Version of Dementia Quality of Life Measure - Proxy in Care Home Residents with Dementia. East Asian Arch Psychiatry 2021; 31:9-12. [PMID: 33753571 DOI: 10.12809/eaap2019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
OBJECTIVE To evaluate psychometric properties of the Chinese version of Dementia Quality of Life Measure - Proxy (C-DEMQoL-Proxy). METHODS Care home residents aged ≥60 years who were diagnosed with dementia or demonstrated impairment in cognition were recruited from four care facilities in Hong Kong. Caregivers of these participants were also invited to participate. The original DEMQoL-Proxy was translated into Chinese (Cantonese) by a trained translator. The forward-translated version was reviewed by an expert panel of six experienced healthcare professionals. Revisions were made based on comments. The instrument was back-translated to English to check whether further changes were necessary. Demographic data (age, sex, type and severity of dementia, and Mini-Mental State Examination [MMSE] score) were collected from medical records of participants with dementia. Caregivers were interviewed by an occupational therapist or personnel supervised by the occupational therapist using the C-DEMQoL-Proxy and the Chinese version of Quality of Life-Alzheimer's Disease-Proxy (C-QoL-AD-Proxy). Acceptability, reliability, and validity of the C-DEMQoL-Proxy were evaluated using standard psychometric methods. RESULTS 90 individuals (82.2% women) with dementia aged 72 to 102 years were included. Their diagnosis included Alzheimer's disease (23.3%), vascular dementia (15.6%), mixed and other types of dementias (51.1%), and missing (10%). Severity was mild in 12.2%, moderate in 62.2%, and severe in 25.6%. The mean MMSE score was 12.0 ± 4.9. 20% of the caregivers were family members and the rest were professional carers. The C-DEMQoL-Proxy had good acceptability, with no floor or ceiling effects or missing data. It had good internal consistency (Cronbach alpha = 0.91) and test-retest reliability (intraclass correlation coefficients = 0.83). It was mildly correlated with C-QoL-AD-Proxy (r = 0.29, p < 0.01). Age and sex were not correlated with C-DEMQoL-Proxy scores. C-DEMQoL-Proxy scores were not significantly different between dementia types, severity levels, or between those with higher or lower MMSE scores. CONCLUSION The C-DEMQoL-Proxy is a valid and reliable instrument to assess health-related quality of life in individuals with dementia.
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Teo KC, Leung WCY, Wong YK, Liu RKC, Chan AHY, Choi OMY, Kwok WM, Leung KK, Tse MY, Cheung RTF, Tsang ACO, Lau KK. Delays in Stroke Onset to Hospital Arrival Time During COVID-19. Stroke 2020; 51:2228-2231. [PMID: 32432998 PMCID: PMC7258759 DOI: 10.1161/strokeaha.120.030105] [Citation(s) in RCA: 161] [Impact Index Per Article: 40.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Background and Purpose: The current coronavirus disease 2019 (COVID-19) pandemic represents a global public health crisis, disrupting emergency healthcare services. We determined whether COVID-19 has resulted in delays in stroke presentation and affected the delivery of acute stroke services in a comprehensive stroke center in Hong Kong. Methods: We retrospectively reviewed all patients with transient ischemic attack and stroke admitted via the acute stroke pathway of Queen Mary Hospital, Hong Kong, during the first 60 days since the first diagnosed COVID-19 case in Hong Kong (COVID-19: January 23, 2020–March 24, 2020). We compared the stroke onset to hospital arrival (onset-to-door) time and timings of inpatient stroke pathways with patients admitted during the same period in 2019 (pre–COVID-19: January 23, 2019–March 24, 2019). Results: Seventy-three patients in COVID-19 were compared with 89 patients in pre–COVID-19. There were no significant differences in age, sex, vascular risk factors, nor stroke severity between the 2 groups (P>0.05). The median stroke onset-to-door time was ≈1-hour longer in COVID-19 compared with pre–COVID-19 (154 versus 95 minutes, P=0.12), and the proportion of individuals with onset-to-door time within 4.5 hours was significantly lower (55% versus 72%, P=0.024). Significantly fewer cases of transient ischemic attack presented to the hospital during COVID-19 (4% versus 16%, P=0.016), despite no increase in referrals to the transient ischemic attack clinic. Inpatient stroke pathways and treatment time metrics nevertheless did not differ between the 2 groups (P>0.05 for all comparisons). Conclusions: During the early containment phase of COVID-19, we noted a prolongation in stroke onset to hospital arrival time and a significant reduction in individuals arriving at the hospital within 4.5 hours and presenting with transient ischemic attack. Public education about stroke should continue to be reinforced during the COVID-19 pandemic.
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Wong YK, Cheung CYY, Tang CS, Hai JSH, Lee CH, Lau KK, Au KW, Cheung BMY, Sham PC, Xu A, Lam KSL, Tse HF. High-sensitivity troponin I and B-type natriuretic peptide biomarkers for prediction of cardiovascular events in patients with coronary artery disease with and without diabetes mellitus. Cardiovasc Diabetol 2019; 18:171. [PMID: 31847896 PMCID: PMC6918569 DOI: 10.1186/s12933-019-0974-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 12/03/2019] [Indexed: 12/16/2022] Open
Abstract
Background High-sensitivity troponin I (hs-Tnl) and B-type natriuretic peptide (BNP) are promising prognostic markers for coronary artery disease (CAD). This prospective cohort study investigated whether a combination of these cardiac biomarkers with conventional risk factors would add incremental value for the prediction of secondary major adverse cardiovascular events (MACEs) in patients with CAD, with and without type 2 diabetes mellitus (T2DM). Methods Baseline plasma level of hs-Tnl and BNP was measured in 2275 Chinese patients with stable CAD. Patients were monitored for new-onset of MACE over a median of 51 months. Cox proportional hazard model and area under the receiver operating characteristic curve (AUC) were used to assess the association of cardiac biomarkers with MACE and their predictive values in relationship with or without T2DM. Results During the follow up period 402 (18%) patients experienced a new-onset MACE with hs-Tnl and BNP level significantly higher than in those without MACE. In multivariable analyses, patients with elevated hs-Tnl (hazard ratio, 1.75 [95% CI 1.41–2.17]; P < 0.001) and BNP (hazard ratio, 1.42 [95% CI 1.15–1.75]; P = 0.001) were significantly associated with an increased risk of MACE after adjustment for variables of a risk factor model of age, sex, T2DM and hypertension. The risk factor model had an AUC of 0.64 for MACE prediction. The AUC significantly increased to 0.68 by the addition of hs-Tnl to the risk factor model. Subgroup analyses showed that hs-Tnl and BNP remained significant predictors of MACE in both patients with and without T2DM in multivariable models with higher risk of MACE evident in those without T2DM. Among patients without T2DM, addition of each biomarker yielded greater predictive accuracy than in T2DM patients, with AUC further increased to 0.75 when a combination of hs-Tnl and BNP was added to the risk factor model (age, sex and hypertension). Conclusions Elevated hs-Tnl and BNP level are independent predictors of new-onset MACE in CAD patients, irrespective of diabetes status. Among CAD patients without T2DM, a combination of cardiac biomarkers hs-Tnl and BNP yield the greatest predictive value beyond conventional risk factors.
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Wong YK, Cheung CYY, Tang CS, Au KW, Hai JSH, Lee CH, Lau KK, Cheung BMY, Sham PC, Xu A, Lam KSL, Tse HF. Age-Biomarkers-Clinical Risk Factors for Prediction of Cardiovascular Events in Patients With Coronary Artery Disease. Arterioscler Thromb Vasc Biol 2019; 38:2519-2527. [PMID: 30354221 DOI: 10.1161/atvbaha.118.311726] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Objective- In patients with stable coronary artery disease, conventional risk factors provide limited incremental predictive value for cardiovascular events. We sought to investigate whether a panel of cardiometabolic biomarkers alone or combined with conventional risk factors would exhibit incremental value in the prediction of cardiovascular events. Approach and Results- In the discovery cohort, we measured serum adiponectin, A-FABP (adipocyte fatty acid-binding protein), lipocalin-2, FGF (fibroblast growth factor)-19 and 21, plasminogen activator inhibitor-1, and retinol-binding protein-4 in 1166 Chinese coronary artery disease patients. After a median follow-up of 35 months, 170 patients developed new-onset major adverse cardiovascular events (MACE). In the model with age ≥65 years and conventional risk factors, area under the curve for predicting MACE was 0.68. Addition of lipocalin-2 to the age-clinical risk factor model improved predictive accuracy (area under the curve=0.73). Area under the curve further increased to 0.75 when a combination of lipocalin-2, A-FABP, and FGF-19 was added to yield age-biomarkers-clinical risk factor model. The adjusted hazard ratio on MACEs for lipocalin-2, A-FABP, and FGF-19 levels above optimal cutoffs were 2.23 (95% CI, 1.62-3.08), 1.99 (95% CI, 1.43-2.76), and 1.65 (95% CI, 1.15-2.35), respectively. In the validation cohort of 1262 coronary artery disease patients with type 2 diabetes mellitus, the age-biomarkers-clinical risk factor model was confirmed to provide good discrimination and calibration over the conventional risk factor alone for prediction of MACE. Conclusions- A combination of the 3 biomarkers, lipocalin-2, A-FABP, and FGF-19, with clinical risk factors to yield the age-biomarkers-clinical risk factor model provides an optimal and validated prediction of new-onset MACE in patients with stable coronary artery disease.
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Hai JJ, Wong YK, Wong CK, Un KC, Chan PH, Siu CW, Yiu KH, Lau CP, Tse HF. Prognostic implications of statin intolerance in stable coronary artery disease patients with different levels of high-sensitive troponin. BMC Cardiovasc Disord 2019; 19:168. [PMID: 31307391 PMCID: PMC6633694 DOI: 10.1186/s12872-019-1152-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 07/08/2019] [Indexed: 12/27/2022] Open
Abstract
Background The prognostic implication of statin in tolerance (SI) in those with stable CAD remains unclear. We hypothesized that SI is of higher prognostic significance in stable CAD patients with elevated high-sensitive cardiac troponin I (hs-cTnI). Methods A total of 952 stable CAD patients from the prospective Hong Kong CAD study who had complete clinical data, biomarker measurements and who were prescribed statin therapy were studied. Results We identified 13 (1.4%) and 125 (13.1%) patients with complete and partial SI, respectively. At baseline, patients with SI were more likely to have diabetes mellitus and a higher hs-cTnI level, but no difference in LDL-C level compared with those without SI. After 51 months of follow-up, patients with SI had a higher mean LDL-C level than those without SI. A total of 148 (15.5%) patients developed major adverse cardiovascular events (MACEs). Both SI (HR 1.52, 95% CI 1.06–2.19, P = 0.02) and elevated hs-cTnI (HR 3.18, 95% CI 2.07–4.89, P < 0.01) were independent predictors of a MACE in patients with stable CAD. When stratified by hs-cTnI level, SI independently predicted MACE-free survival only in those with elevated hs-cTnI (HR 1.51, 95% CI 1.01–2.24, P = 0.04). Conclusions SI independently predicted MACE in patients with stable CAD and high hs-cTnI, but not in those with low hs-cTnI. Hs-cTnI may be used to stratify stable CAD patients who have SI for intensive lipid-lowering therapy using non-statin agents. Electronic supplementary material The online version of this article (10.1186/s12872-019-1152-x) contains supplementary material, which is available to authorized users.
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So CW, Lui CT, Tsui KL, Chan KL, Law AKK, Wong YK, Li T, Wong CL, Leung SC. Questionnaire survey on medical futility and termination of resuscitation in cardiac arrest patients among emergency physicians in Hong Kong. Hong Kong Med J 2019; 25:183-191. [PMID: 31178438 DOI: 10.12809/hkmj187755] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
INTRODUCTION The perceptions of medical futility and decisions about termination of resuscitation (TOR) for out-of-hospital cardiac arrest (OHCA) are highly heterogeneous and dependent on the practice of the attending emergency physicians. The objective of this study was to report and investigate the knowledge, attitudes, and practices regarding medical futility and TOR during management of OHCA in Hong Kong. METHODS A cross-sectional survey was conducted among emergency medicine physicians in Hong Kong. The questionnaire assessed participants' background, knowledge, attitudes, and behaviours concerning medical futility and TOR in management of OHCA. Composite scores were calculated to reflect knowledge, attitudes, and practices of OHCA treatment. Subgroup analysis and multiple regression analysis were used to explore the relationship between participants' background, knowledge, attitudes, and behaviours. RESULTS The response rate to this survey was 57% (140/247). Independent predictors of less aggressive resuscitation in OHCA patients included status as a Fellow of the Hong Kong College of Emergency Medicine (β= -0.314, P=0.028) and being an Advanced Cardiac Life Support instructor (β= -0.217, P=0.032). There was no difference in aggressiveness of resuscitation in terms of years of clinical experience (β=0.015, P=0.921), knowledge of TOR (β=0.057, P=0.509), or attitudes about TOR (β= -0.103, P=0.214). The correlation between knowledge and attitudes was low (Spearman's coefficient=0.02, P=0.795). CONCLUSION Clinical practice and behaviour of TOR was not demonstrated to have associations with knowledge or attitude. Status as a Fellow of the Hong Kong College of Emergency Medicine or Advanced Cardiac Life Support instructor were the only two parameters identified that had significant relationships with earlier TOR in medically futile patients with OHCA.
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Wong YK, Pan NY, Chu CY, Chan TN. Diagnosing Epiglottitis with Radiographs: Can we be More Objective? HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791602300306] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Objective The classical radiographic signs in acute epiglottitis are qualitative. The purpose of our study was to identify objective radiographic parameters to aid diagnosis of acute epiglottitis in Chinese adults. Methods A case-control study of Chinese adult patients attending the accident and emergency department (AED) who were subsequently diagnosed to have acute epiglottitis from 1st January 2009 to 31st December 2013 in a public hospital in Hong Kong. Controls were one-to-one age- and sex-matched patients who attended the AED during the study period for orthopaedic problems with cervical spine radiographs taken. Cases and controls were retrieved from the hospital computer system and their radiographs were interpreted by two specialist radiologists with various pharyngeal and laryngeal parameters, including the dimensions of the third cervical vertebral body, epiglottis, aryepiglottic fold, hypopharynx, retropharyngeal soft tissue and retrotracheal soft tissue, measured and analysed. Sensitivity, specificity, positive and negative likelihood ratios were calculated for each of the parameters. Results Twenty-six patients and 26 age- and sex-matched controls were included in the study. Epiglottis width of 5.5 mm or more was found to be 96.2% sensitive and 100% specific in diagnosing acute epiglottitis. Positive and negative likelihood ratios were infinity and 0.04 respectively. Aryepiglottic fold width of 5.9 mm or more was 92.3% sensitive and 80.8% specific. Positive and negative likelihood ratios were 4.80 and 0.10 respectively. Conclusion The identified objective radiographic parameters should aid in the diagnosis of acute epiglottitis in Chinese adults. (Hong Kong j. emerg.med. 2016;23:168-175)
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Wong YK, Ho YH, Leung HM, Ho KC, Yau YH, Yung KKL. Enhancement of Chlorella vulgaris harvesting via the electro-coagulation-flotation (ECF) method. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:9102-9110. [PMID: 28039627 DOI: 10.1007/s11356-016-7856-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 10/06/2016] [Indexed: 06/06/2023]
Abstract
This article explores the potential of using an electro-coagulation-flotation (ECF) harvester to allow flotation of microalgae cells for surface harvesting. A response surface methodology (RSM) model was used to optimize ECF harvesting by adjusting electrode plate material, electrode plate number, charge of the electrodes, electrolyte concentration, and pH value of the culture solution. The result revealed that three aluminum electrode plates (one anode and two cathodes), brine solution (8 g/L), and acidity (pH = 4) of culture solution (optimized ECF harvester) The highest flocculant concentration was measured at 2966 mg/L after 60 min and showed a 79.8 % increase of flocculation concentration. Such results can provide a basis for designing a large-scale microalgae harvester for commercial use in the future.
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Leung HM, Duzgoren-Aydin NS, Au CK, Krupanidhi S, Fung KY, Cheung KC, Wong YK, Peng XL, Ye ZH, Yung KKL, Tsui MTK. Monitoring and assessment of heavy metal contamination in a constructed wetland in Shaoguan (Guangdong Province, China): bioaccumulation of Pb, Zn, Cu and Cd in aquatic and terrestrial components. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:9079-9088. [PMID: 27164879 DOI: 10.1007/s11356-016-6756-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 04/25/2016] [Indexed: 06/05/2023]
Abstract
The objective of this study is to evaluate the current status of heavy metal concentrations in constructed wetland, Shaoguan (Guangdong, China). Sediments, three wetland plants (Typha latifolia, Phragmites australis, and Cyperus malaccensis), and six freshwater fish species [Carassius auratus (Goldfish), Cirrhinus molitorella (Mud carp), Ctenopharyngodon idellus (Grass carp), Cyprinus carpio (Wild common carp), Nicholsicypris normalis (Mandarin fish), Sarcocheilichthys kiangsiensis (Minnows)] in a constructed wetland in Shaoguan were collected and analyzed for their heavy metal compositions. Levels of Pb, Zn, Cu, and Cd in sediments exceeded approximately 532, 285, 11, and 66 times of the Dutch Intervention value. From the current study, the concentrations of Pb and Zn in three plants were generally high, especially in root tissues. For fish, concentrations of all studied metals in whole body of N. mormalis were the highest among all the fishes investigated (Pb 113.4 mg/kg, dw; Zn 183.1 mg/kg, dw; Cu 19.41 mg/kg, dw; 0.846 mg/kg, dw). Heavy metal accumulation in different ecological compartments was analyzed by principle component analysis (PCA), and there is one majority of grouped heavy metals concentration as similar in composition of ecological compartment, with the Cd concentration quite dissimilar. In relation to future prospect, phytoremediation technology for enhanced heavy metal accumulation by constructed wetland is still in early stage and needs more attention in gene manipulation area.
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Wong YK, Ho YH, Ho KC, Leung HM, Yung KKL. Maximization of cell growth and lipid production of freshwater microalga Chlorella vulgaris by enrichment technique for biodiesel production. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:9089-9101. [PMID: 27975198 DOI: 10.1007/s11356-016-7792-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 09/28/2016] [Indexed: 06/06/2023]
Abstract
Chlorella vulgaris was cultivated under limitation and starvation and under controlled conditions using different concentrations of nitrate (NaNO3) and phosphate (K2HPO4 and KH2PO4) chemicals in modified Bold basal medium (BBM). The biomass and lipid production responses to different media were examined in terms of optical density, cell density, dry biomass, and lipid productivity. In the 12-day batch culture period, the highest biomass productivity obtained was 72.083 mg L-1 day-1 under BBM - NcontrolPlimited condition. The highest lipid content, lipid concentration, and lipid productivity obtained were 53.202 %, 287.291 mg/L, and 23.449 mg L-1 day-1 under BBM - NControlPDeprivation condition, respectively. Nitrogen had a major effect in the biomass concentration of C. vulgaris, while no significant effect was found for phosphorus. Nitrogen and phosphorus starvation was found to be the strategy affecting the lipid accumulation and affected the lipid composition of C. vulgaris cultures.
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Chan JTK, Leung HM, Yue PYK, Au CK, Wong YK, Cheung KC, Li WC, Yung KKL. Combined effects of land reclamation, channel dredging upon the bioavailable concentration of polycyclic aromatic hydrocarbons (PAHs) in Victoria Harbour sediment, Hong Kong. MARINE POLLUTION BULLETIN 2017; 114:587-591. [PMID: 27634738 DOI: 10.1016/j.marpolbul.2016.09.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 09/07/2016] [Accepted: 09/10/2016] [Indexed: 06/06/2023]
Abstract
The up-to-date concentration of polycyclic aromatic hydrocarbons (PAHs) in sediment materials of Victoria Harbour was investigated so as to evaluate the pollution potential associated with the reclamation projects in Hong Kong. A total of 100 sediment samples were collected at 20 locations. Except the control point in reservoir, the PAHs concentrations were detectable levels all sites (131-628.3ng/g, dw) and such values were higher than Dutch Target and Intervention Values (the New Dutch standard in 2016). The PAHs concentration indicating that construction waste and wastewater discharges were the main pollutant sources. Results of correlation in single cell gel electrophoresis assay (comet assay) studies also revealed that the PAHs concentration was highly correlated (<0.01) with DNA migration (i.e. the length of tail moment of fish cells) in 5mg/ml of PAHs. The above observation indicates that the PAHs present in the sediment may substantially effect the marine ecosystem. Although the dredged sediment can be a useful sea-filling material for land reclamation; however, the continuing leaching of PAHs and its impact on the aquatic environment need to be studied further.
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