2.Carbon monoxide: present and future indications for a medical gas.
Stefan W RYTER ; Augustine M K CHOI
The Korean Journal of Internal Medicine 2013;28(2):123-140
Gaseous molecules continue to hold new promise in molecular medicine as experimental and clinical therapeutics. The low molecular weight gas carbon monoxide (CO), and similar gaseous molecules (e.g., H2S, nitric oxide) have been implicated as potential inhalation therapies in inflammatory diseases. At high concentration, CO represents a toxic inhalation hazard, and is a common component of air pollution. CO is also produced endogenously as a product of heme degradation catalyzed by heme oxygenase enzymes. CO binds avidly to hemoglobin, causing hypoxemia and decreased oxygen delivery to tissues at high concentrations. At physiological concentrations, CO may have endogenous roles as a signal transduction molecule in the regulation of neural and vascular function and cellular homeostasis. CO has been demonstrated to act as an effective anti-inflammatory agent in preclinical animal models of inflammation, acute lung injury, sepsis, ischemia/reperfusion injury, and organ transplantation. Additional experimental indications for this gas include pulmonary fibrosis, pulmonary hypertension, metabolic diseases, and preeclampsia. The development of chemical CO releasing compounds constitutes a novel pharmaceutical approach to CO delivery with demonstrated effectiveness in sepsis models. Current and pending clinical evaluation will determine the usefulness of this gas as a therapeutic in human disease.
Administration, Inhalation
;
Animals
;
Anti-Inflammatory Agents/administration & dosage/adverse effects/metabolism/*therapeutic use
;
Carbon Monoxide/administration & dosage/adverse effects/metabolism/*therapeutic use
;
Dose-Response Relationship, Drug
;
Environmental Pollutants/adverse effects
;
Gases
;
Heme/metabolism
;
Heme Oxygenase (Decyclizing)/metabolism
;
Humans
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Inhalation Exposure/adverse effects
;
Risk Assessment
;
Signal Transduction
3.Outbreak of pandemic influenza A (H1N1-2009) in Singapore, May to September 2009.
Jeffery L CUTTER ; Li Wei ANG ; Florence Y L LAI ; Hariharan SUBRAMONY ; Stefan MA ; Lyn JAMES
Annals of the Academy of Medicine, Singapore 2010;39(4):273-210
INTRODUCTIONThe fi rst case of pandemic influenza A(H1N1) was detected in Singapore on 26 May 2009, 1 month after the fi rst cases of novel influenza A(H1N1) was reported in California and Texas in the United States. The World Health Organization declared the fi rst influenza pandemic of the 21st century on 11 June 2009.
MATERIALS AND METHODSConfirmed cases notified to the Ministry of Health between 27 May and 9 July 2009 were analysed. Various indicators of influenza activity were monitored throughout the study period. Estimates of the number of cases of H1N1-2009 were made using the number of polyclinic attendances for acute respiratory infection and influenza-like illness and the weekly prevalence of H1N1-2009.
RESULTSCases in Singapore affected mainly young adults, youths and children. By the end of September 2009, it was estimated that at least 270,000 persons had been infected by pandemic influenza A (H1N1) in Singapore. The peak number of cases occurred during E-week 30 (26 July-1 August) when an estimated 45,000 cases were seen in polyclinics and GP clinics. The hospitalisation, severe illness and mortality rates were estimated at 6 per 1000 cases, 0.3 per 1000 cases and 6.7 per 100,000 cases, respectively. The most common risk factors among hospitalised adult cases were asthma and diabetes. For hospitalised children, the most common risk factors were being under 5 years of age and asthma. The most common risk factors among persons with severe illness were diabetes in adults and epilepsy and being under 5 years of age in children. About half of cases with severe illness required mechanical ventilation. In addition, one-fifth of cases with severe illness had acute respiratory distress syndrome.
CONCLUSIONSThe fi rst wave of the influenza pandemic lasted about 10 weeks. Morbidity and mortality resulting from pandemic influenza were low.
Adolescent ; Adult ; Child ; Child, Preschool ; Comorbidity ; Disease Outbreaks ; Female ; Hospitalization ; Humans ; Infant ; Influenza A Virus, H1N1 Subtype ; isolation & purification ; Influenza, Human ; diagnosis ; epidemiology ; mortality ; Male ; Middle Aged ; Risk Factors ; Singapore ; epidemiology ; Young Adult
4.A cross-sectional study on reference ranges of normal oral temperatures among students in Singapore.
Yoke Pin KWANG ; Stefan MA ; Seo Yi CHNG ; Frances M L CHIA ; Kam Kei LEONG
Annals of the Academy of Medicine, Singapore 2009;38(7):613-618
INTRODUCTIONDuring the 2003 Severe Acute Respiratory Syndrome (SARS) outbreak, all schools in Singapore implemented twice-daily temperature monitoring for students to curtail the spread of the disease. Students were not allowed to attend school if their temperature readings were >37.8 degrees C for students < or =12 years old, or > or =37.5 degrees C for students >12 years old. These values had been arbitrarily determined with professional inputs. The aim of this study is to determine the reference ranges of normal oral temperatures of students in Singapore and recommend the cut-off values for febrile patients. This may be used in another similar outbreak of an infectious disease with fever.
MATERIALS AND METHODSFour co-ed primary schools and 4 co-ed secondary schools were selected for this study. Four thousand and two hundred primary 1 to secondary 3 students responded (96.8%) and participated in this cross-sectional study. The mean ages of the students in the lowest (primary 1) and highest educational levels (secondary 3) were 7.4 years old and 15.3 years old, respectively. Twelve oral temperature readings per student (i.e. measurements taken 4 times a day in 3 consecutive days) were collected. Forty-six thousand seven hundred and eighty-three (92.8%) out of 50,400 temperature readings were used for the analysis as missing data were excluded. A quantile regression model was applied to estimate reference ranges of normal oral temperatures for students with adjustment for potential confounding factors.
RESULTSThe age-specific reference ranges of normal oral temperature from this study for students < or =12 years old and >12 years old were 35.7 degrees C to 37.7 degrees C and 35.6 degrees C to 37.4 degrees C, respectively. Temperatures of 37.8 degrees C and 37.5 degrees C are therefore recommended as the oral temperature cut-offs for those < or =12 years old and >12 years old, respectively.
CONCLUSIONThis study has provided empirical data on normal oral temperature cut-offs which could be used during temperature screening in schools.
Adolescent ; Body Temperature ; Child ; Circadian Rhythm ; Cross-Sectional Studies ; Female ; Humans ; Male ; Reference Values ; Schools ; Singapore ; Students
5.Normative Data for the Singapore English and Chinese SF-36 Version 2 Health Survey.
Wei Ting SOW ; Hwee Lin WEE ; Yi WU ; E-Shyong TAI ; Barbara GANDEK ; Jeannette LEE ; Stefan MA ; Derrick HENG ; Julian THUMBOO
Annals of the Academy of Medicine, Singapore 2014;43(1):15-23
INTRODUCTIONThe aim of this study is to report normative data for the Short-Form 36 version 2 (SF-36v2) for assessing health-related quality of life, in the Singapore general population.
MATERIALS AND METHODSData for English and Chinese-speaking participants of the Singapore Prospective Study Programme were analysed. The SF-36v2 scores were norm-based with the English-speaking Singapore general population as reference and reported by age (in decades), gender and ethnicity as well as for the 5 most prevalent chronic medical conditions. Scores were reported separately for the English and Chinese language versions.
RESULTSA total of 6151 English-speaking (61.5% Chinese and 19.2% Malay) and 1194 Chinese-speaking participants provided complete data. Mean (SD) age of all participants was 49.6 (12.58) years with 52.4% being women. In both languages, women reported lower scores than men on all scales. Among the chronic medical conditions, stroke had the largest impact on all English SF-36v2 scales and on 3 Chinese SF-36v2 scales (role-physical, general health and social functioning).
CONCLUSIONWe have provided detailed normative data for the Singapore English and Chinese SF-36v2, which would be valuable in furthering HRQoL research in Singapore and possibly the region.
Adult ; Female ; Health Surveys ; standards ; statistics & numerical data ; Humans ; Language ; Male ; Middle Aged ; Prospective Studies ; Quality of Life ; Singapore ; Young Adult
6.Rationale for redefining obesity in Asians.
Serena LOW ; Mien Chew CHIN ; Stefan MA ; Derrick HENG ; Mabel DEURENBERG-YAP
Annals of the Academy of Medicine, Singapore 2009;38(1):66-69
INTRODUCTIONThere has been extensive research on defining the appropriate body mass index (BMI) cut-off point for being overweight and obese in the Asian population since the World Health Organisation (WHO) Expert Consultation Meeting in 2002.
MATERIALS AND METHODSWe reviewed the literature on the optimal BMI cut-off points for Asian populations. We searched PubMed, EMBASE, National Institute for Health Research Centre for Reviews and Dissemination (NHS CRD) Database, Cochrane Library and Google. Attempts to identify further studies were made by examining the reference lists of all retrieved articles. There were 18 articles selected for the review.
RESULTSThere were 13 studies which have identified the BMI cut-off points for Asian populations lower than the international BMI cut-off points recommended by the WHO. Many of the studies have recommended lowering BMI cut-off point specific for Asian populations. A few studies concurred with the recommended cut-off point for Asian populations recommended by International Association for the Study of Obesity (IASO), the International Obesity Task Force (IOTF) and the WHO in 2002. Asian populations were also noted to have higher cardiovascular risk factors than Western populations at any BMI level.
CONCLUSIONSFurther research would be needed to look at the all-cause mortality at same BMI levels between Asians and Caucasians in order to evaluate the BMI cut-off recommendations for Asian populations. It is necessary to develop and redefine appropriate BMI cut-off points which are country-specific and ethnic-specific for Asians. These will facilitate the development of appropriate preventive interventions to address the public health problem posed by obesity.
Asian Continental Ancestry Group ; Body Mass Index ; Humans ; Obesity ; diagnosis ; Reference Values
7.Health Screening Behaviour among Singaporeans.
Hui Zhen WONG ; Wei Yen LIM ; Stefan Sl MA ; Lily Av CHUA ; Derrick Mk HENG
Annals of the Academy of Medicine, Singapore 2015;44(9):326-334
INTRODUCTIONThis study assessed the health screening behaviour of Singaporeans and evaluated factors associated with low uptake of screening tests.
MATERIALS AND METHODSData from the 2010 National Health Survey, which was conducted on Singapore citizens and permanent residents, was used in this analysis. Multivariate Cox regression was used to evaluate the relationship between sociodemographics and health screening behaviour for selected chronic diseases (hypertension, diabetes and hypercholesterolaemia) and cancers (cervical, breast and colorectal). National recommendations for age at which screening should be initiated and appropriate screening interval were used to define appropriate screening behaviour.
RESULTSMore respondents have had their last chronic disease screening done within the recommended time period compared to cancer screening. A total of 77.8%, 63.4% and 54.9% of the respondents had their last hypertension, diabetes and hypercholesterolaemia done within the recommended time period respectively, while less than 50% of the respondents had their cervical (45.8%), breast (32.9%) and colorectal (20.2%) cancer screenings done within the recommended time period. Respondents with higher household income or more years of education were more likely to have undergone screening within the recommended time period. Indians, who are at higher risk of chronic diseases such as diabetes and hypercholesterolaemia, were also more likely to have been screened. A total of 69.9% and 79.5% of the respondents with previously undiagnosed diabetes and hypertension had reported to have done diabetes and hypertension screenings respectively, within the recommended time period.
CONCLUSIONSociodemographic factors that could be associated with a lower uptake of screening tests include: 1) low household income, 2) low education level, and 3) Malay ethnicity. Health promotion programmes and outreach to these groups can be enhanced to further improve screening uptake.
Adult ; Aged ; Breast Neoplasms ; diagnostic imaging ; Colonoscopy ; utilization ; Colorectal Neoplasms ; diagnosis ; Diabetes Mellitus ; diagnosis ; Early Detection of Cancer ; utilization ; Female ; Health Behavior ; Humans ; Hypercholesterolemia ; diagnosis ; Hypertension ; diagnosis ; Male ; Mammography ; utilization ; Mass Screening ; utilization ; Middle Aged ; Neoplasms ; diagnosis ; Occult Blood ; Papanicolaou Test ; utilization ; Proportional Hazards Models ; Singapore ; Surveys and Questionnaires ; Uterine Cervical Neoplasms ; diagnosis ; Vaginal Smears ; utilization
8.Validity of a Revised Short Form-12 Health Survey Version 2 in Different Ethnic Populations.
Maudrene Ls TAN ; Hwee Lin WEE ; Agus SALIM ; Jeannette LEE ; Stefan MA ; Derrick HENG ; E Shyong TAI ; Julian THUMBOO
Annals of the Academy of Medicine, Singapore 2016;45(6):228-236
INTRODUCTIONThe Short Form-12 version 2 (SF-12v2) is a shorter version of the Short Form-36 version 2 (SF-36v2) for assessing health-related quality of life. As the SF-12v2 could not be resolved into the physical- and mental-component summary score (PCS and MCS, respectively) in the general population of Singapore, this study aims to determine and validate the Singapore SF-12 version 2 (SG-12v2).
MATERIALS AND METHODSThe SG- 12v2 was generated using the same methodology as the SF-12v2. Bootstrap analysis was used to determine if the SG-12v2 were significantly different from the SF-12v2. Content validity was assessed using percentage of variance (R²) of the Singapore version of SF-36v2 PCS and MCS explained by the SG-12v2 items. Agreement between the SF-36v2 and the SG-12v2 was assessed using Bland-Altman diagrams. Criterion validity was demonstrated if effect size differences between SF-36v2 and SG-12v2 were small (Cohen's criteria). Known-group validity of SG-12v2 was reported for participants with and without chronic diseases.
RESULTSFive items differed between the SG-12v2 and SF-12v2. Bootstrap analysis confirmed that SG-12v2 and SF-12v2 were significantly different. The SG12v2 explained 94% and 79% of the R² of the SF-36v2 PCS and MCS, respectively. Agreement was good and effect size differences were small (<0.3). Participants with chronic diseases reported lower SG-12v2 scores compared to participants without chronic diseases.
CONCLUSIONThe SG-12v2 offers advantage over the SF-12v2 for use in the general population of Singapore. The SG-12v2 is a valid measure and will be particularly useful for large population health surveys in Singapore.
Asian Continental Ancestry Group ; Chronic Disease ; Ethnic Groups ; Health Status ; Health Surveys ; Humans ; Quality of Life ; Reproducibility of Results ; Singapore
9.Epidemiology and control of SARS in Singapore.
Kee-Tai GOH ; Jeffery CUTTER ; Bee-Hoon HENG ; Stefan MA ; Benjamin K W KOH ; Cynthia KWOK ; Cheong-Mui TOH ; Suok-Kai CHEW
Annals of the Academy of Medicine, Singapore 2006;35(5):301-316
Severe acute respiratory syndrome (SARS) was imported into Singapore in late February 2003 by a local resident who returned from a holiday in Hong Kong and started an outbreak in the hospital where she was admitted on 1 March 2003. The disease subsequently spread to 4 other healthcare institutions and a vegetable wholesale centre. During the period between March and May 2003, 238 probable SARS cases, including 8 imported cases and 33 deaths, were reported. Transmission within the healthcare and household settings accounted for more than 90% of the cases. Factors contributing to the spread of infection included the failure to recognise the high infectivity of this novel infection, resulting in a delay in isolating initial cases and contacts and the implementation of personal protective measures in healthcare institutions; and the super-spreading events by 5 index cases, including 3 with co-morbid conditions presenting with atypical clinical manifestations of SARS. Key public health measures were directed at prevention and control within the community and hospitals, and the prevention of imported and exported cases. An isolated laboratory-acquired case of SARS was reported on 8 September 2003. Based on the lessons learnt, Singapore has further strengthened its operational readiness and laboratory safety to respond to SARS, avian flu and other emerging diseases.
Adolescent
;
Adult
;
Aged
;
Aged, 80 and over
;
Child
;
Child, Preschool
;
Disease Outbreaks
;
prevention & control
;
statistics & numerical data
;
Disease Transmission, Infectious
;
prevention & control
;
Female
;
Humans
;
Infant
;
Infant, Newborn
;
Male
;
Middle Aged
;
Retrospective Studies
;
Severe Acute Respiratory Syndrome
;
epidemiology
;
transmission
;
Singapore
;
epidemiology
10.Changes in the prevalence of comorbidity of mental and physical disorders in Singapore between 2010 and 2016.
Edimansyah ABDIN ; Siow Ann CHONG ; Janhavi Ajit VAINGANKAR ; Saleha SHAFIE ; Darren SEAH ; Chun Ting CHAN ; Stefan MA ; Lyn JAMES ; Derrick HENG ; Mythily SUBRAMANIAM
Singapore medical journal 2022;63(4):196-202
INTRODUCTION:
Few studies have examined the changes in the prevalence of comorbidity of mental and physical disorders in recent years. The present study sought to examine whether the prevalence of comorbidity of mental and physical disorders in Singapore showed any changes between 2010 and 2016.
METHODS:
We extracted data from two repeated nationally representative cross-sectional surveys conducted among resident adults aged ≥ 18 years in Singapore. Significant changes were tested using pooled multinomial logistic regression analyses.
RESULTS:
The prevalence of comorbid mental and physical disorders increased significantly from 5.8% in 2010 to 6.7% in 2016. Among those with physical disorders, there were significant increases over time in the prevalence of comorbid generalised anxiety disorder (GAD) (0.1% vs. 0.4%) and obsessive-compulsive disorder (OCD) (1.4% vs. 3.9%) in diabetes mellitus, and alcohol dependence in cardiovascular disorders (0.1% vs. 1.3%). Among those with mental disorders, there were significant increases over time in the prevalence of comorbid diabetes mellitus in OCD (4.1% vs. 10.9%), cancer in major depressive disorder (0.4% vs. 2.4%), and cardiovascular disorders in GAD (0.4% vs. 6.7%) and alcohol dependence (0.9% vs. 11.8%). Significant changes in the overall prevalence of comorbid mental and physical disorders were also observed across age group, education and employment status.
CONCLUSION
The prevalence of comorbid mental and physical disorders increased significantly over time. This finding supports the need for more appropriate clinical management with better integration between mental health and general medical care professionals across all aspects of the healthcare system to treat this comorbidity in Singapore.
Adult
;
Alcoholism/epidemiology*
;
Comorbidity
;
Cross-Sectional Studies
;
Depressive Disorder, Major/epidemiology*
;
Humans
;
Mental Disorders/epidemiology*
;
Prevalence
;
Singapore/epidemiology*