David Chi-Leung Lam

Dr. David Chi-Leung Lam

orcid

Research Focus & Metrics

Academic Career Length

21Years (2006-Present)

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

Representative Publications

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23 April 2015 in Asia Pacific Family Medicine
Verified
Journal Article
Open access
PDF file
SLSam Lim
Sam Lim
DLDavid Chi-Leung Lam
David Chi-Leung Lam
AMAbdul Razak Muttalif
Abdul Razak Muttalif
FYFaisal Yunus
Faisal Yunus
SWSomkiat Wongtim
Somkiat Wongtim
TGTeresita de Guia
Teresita de Guia
Chronic obstructive pulmonary disease (COPD) is a clinical syndrome encompassing a group of chronic, progressive, and debilitating respiratory conditions, that are characterized by incompletely reversible airflow limitation. Within the Asia-Pacific region, prevalence estimates have been derived using various protocols and study methods, and there is little data on the impact of COPD exacerbations. This study aimed to provide a comprehensive picture of the current prevalence and burden of COPD in this region. A population-based survey was conducted in nine Asia-Pacific territories between 01 February 2012 and 16 May 2012. Overall, 112,330 households were screened to identify eligible subjects (aged ≥40 years, with a physician diagnosis of COPD, chronic bronchitis or emphysema, or with identifiable symptoms of chronic bronchitis). Out of a sample of 69,279 individuals aged ≥40 years, 4,289 subjects with COPD were identified. Data were collected via face-to-face interviews or by fixed-line telephone, using a structured questionnaire. A total of 1,841 completed questionnaires were analyzed. The overall estimated COPD prevalence was 6.2%, with 19.1% of subjects having severe COPD. In the 12 months prior to the survey, nearly half of all subjects (46%) had experienced exacerbations, and 19% had been hospitalized as a result of their condition. When subjects were asked about the impact of their condition on employment, 23% said their condition kept them from working, and 42% felt that their condition limited their ability to work or their activities. Of those who reported taking prescription drugs, 20% did not know the name of the drugs they were taking. Prescription of oral corticosteroids was common, with 44% of subjects having used these during the previous year to manage their respiratory symptoms; in contrast, inhaler use was low (25%). Only 37% of subjects had taken a lung function test, and the majority (89%) of those tested did not know their test results. Across the Asia-Pacific territories surveyed, the prevalence of COPD is high, indicating a substantial socioeconomic burden. Our findings suggest that there is considerable room for improvement in the management of COPD, and highlight a need to enhance patient and physician education in the region.

8 March 2013 in Translational Respiratory Medicine
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Journal Article
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SLSusan Y Luo
Susan Y Luo
DLDavid Chi-Leung Lam
David Chi-Leung Lam
Lung cancer is a heterogeneous and complex disease. Genomic and transcriptomic profiling of lung cancer not only further our knowledge about cancer initiation and progression, but could also provide guidance on treatment decisions. The fact that targeted treatment is most successful in a subset of tumors indicates the need for better classification of clinically related molecular tumor phenotypes based on better understanding of the mutations in relevant genes, especially in those oncogenic driver mutations. EGFR gene mutations, KRAS gene mutations, EML4-ALK rearrangements and altered MET signaling are widely recognized alterations that play important roles in both the biological mechanisms and the clinical sensitivity to treatment in lung cancer. In this article, we reviewed the discovery of the clinical values of these oncogenic driver mutations and the clinical studies revealing the prognostic and predictive values of these biomarkers for clinical sensitivity and resistance to anti-EGFR therapy or other targeted therapies. These form the basis of personalized treatment in lung cancer based on biomarker profiles of individual tumor, leading to therapeutic advancement and betterment.

28 April 2021 in Respiratory Research
Verified
Journal Article
Open access
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WKWang Chun Kwok
Wang Chun Kwok
JHJames Chung Man Ho
James Chung Man Ho
TTTerence Chi Chun Tam
Terence Chi Chun Tam
MIMary Sau Man Ip
Mary Sau Man Ip
DLDavid Chi-Leung Lam
David Chi-Leung Lam
Background: Pseudomonas aeruginosa is one of the commonest bacteria colonizing the airway in patients with non-cystic fibrosis bronchiectasis. Pseudomonas aeruginosa colonization is associated with poor outcomes in patients with bronchiectasis, including rapid decline in lung function, exacerbation frequency and hospitalization. Methods: A cross-sectional study in Queen Mary Hospital, Hong Kong that included 350 Chinese patients with non-cystic fibrosis bronchiectasis to investigate the risk factors for Pseudomonas aeruginosa colonization and clinical implications on disease outcomes. Discussions: Pseudomonas aeruginosa colonization was more commonly found in patients with longer duration of bronchiectasis and those on proton pump inhibitors (PPIs) with adjusted ORs of 1.066 (95% CI = 1.036–1.096, p < 0.001) and 2.815 (95% CI = 1.307–6.064, p = 0.008) respectively. Patients with Pseudomonas aeruginosa colonization have more extensive lung involvement and higher risks of exacerbation requiring hospitalization with adjusted ORs of 2.445 (95% CI = 1.283–4.657, p = 0.007) and 2.745 (95% CI = 1.012–7.449, p = 0.047) respectively. Pseudomonas aeruginosa colonization is more common among patients with longer duration of bronchiectasis and those on PPI. Pseudomonas aeruginosa colonization is associated with more extensive lung involvement and higher risks of exacerbation requiring hospitalization.

1 February 2016 in American Journal of Physiology-Lung Cellular and Molecular Physiology
Verified
Journal Article
Open access
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DLDavid Chi-Leung Lam
David Chi-Leung Lam
SLSusan Yang Luo
Susan Yang Luo
KFKin-Hang Fu
Kin-Hang Fu
MLMacy Mei-Sze Lui
Macy Mei-Sze Lui
KCKoon-Ho Chan
Koon-Ho Chan
JMJohn Dorrance Minna
John Dorrance Minna
Nicotine and its derivatives, by binding to nicotinic acetylcholine receptors (nAChRs) on bronchial epithelial cells, can regulate cellular signaling and inflammatory processes. Delineation of nAChR subtypes and their responses to nicotine stimulation in bronchial epithelium may provide information for therapeutic targeting in smoking-related inflammation in the airway. Expression of nAChR subunit genes in 60 bronchial epithelial biopsies and immunohistochemical staining for the subcellular locations of nAChR subunit expression were evaluated. Seven human bronchial epithelial cell lines (HBECs) were exposed to nicotine in vitro for their response in nAChR subunit gene expression to nicotine exposure and removal. The relative normalized amount of expression of nAChR α4, α5, and α7 and immunohistochemical staining intensity of nAChR α4, α5, and β3 expression showed significant correlation with lung function parameters. Nicotine stimulation in HBECs resulted in transient increase in the levels of nAChR α5 and α6 but more sustained increase in nAChR α7 expression. nAChR expression in bronchial epithelium was found to correlate with lung function. Nicotine exposure in HBECs resulted in both short and longer term responses in nAChR subunit gene expression. These results gave insight into the potential of targeting nAChRs for therapy in smoking-related inflammation in the airway.

20 January 2019 in Respirology
Verified
Journal Article
Closed access
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WKWang‐Chun Kwok
Wang‐Chun Kwok
BLBin‐Miao Liang
Bin‐Miao Liang
MLMacy M.S. Lui
Macy M.S. Lui
TTTerence C.C. Tam
Terence C.C. Tam
JSJoycelyn P.Y. Sim
Joycelyn P.Y. Sim
DLDavid Chi-Leung Lam
David Chi-Leung Lam

1 December 2021 in Journal of Stroke and Cerebrovascular Diseases
Verified
Journal Article
Open access
DLDillys Xiaodi Liu
Dillys Xiaodi Liu
DLDavid Chi-Leung Lam
David Chi-Leung Lam
King-Pui Florence ChanKing-Pui Florence Chan
King-Pui Florence Chan
HCHiu-Yeung Chan
Hiu-Yeung Chan
MIMary Sau-Man Ip
Mary Sau-Man Ip
KLKui Kai Lau
Kui Kai Lau
Recent meta-analyses have noted that ∼70% of transient ischemic attack (TIA)/stroke patients have sleep apnea. However, the heterogeneity between studies was high and did not appear to be accounted by the phase of stroke. We conducted an updated meta-analysis and aimed to determine whether the prevalence of sleep apnea amongst stroke patients differs by the subtype, etiology, severity and location of stroke and hence could account for some of the unexplained heterogeneity observed in previous studies. We searched Medline, Embase, CINAHL and Cochrane Library (from their commencements to July 2020) for studies which reported the prevalence of sleep apnea by using polysomnography in TIA/stroke patients. We used random-effects model to calculate the pooled prevalence of sleep apnea and explored whether the prevalence differed by stroke characteristics. Seventy-five studies describing 8670 stroke patients were included in this meta-analysis. The overall prevalence of sleep apnea was numerically higher in patients with hemorrhagic vs. ischemic stroke [82.7% (64.4-92.7%) vs. 67.5% (63.2-71.5%), p=0.098], supratentorial vs. infratentorial stroke [64.4% (56.7-71.4%) vs. 56.5% (42.2-60.0%), p=0.171], and cardioembolic [74.3% (59.6-85.0%)] vs. other ischemic stroke subtypes [large artery atherosclerosis: 68.3% (52.5-80.7%), small vessel occlusion: 56.1% (38.2-72.6%), others/undetermined: 47.9% (31.6-64.6%), p=0.089]. The heterogeneity in sleep apnea prevalence was partially accounted by the subtype (1.9%), phase (5.0%) and location of stroke (14.0%) among reported studies. The prevalence of sleep apnea in the stroke population appears to differ by the subtype, location, etiology and phase of stroke.