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S K Chew

Publications and source records attributed to S K Chew.

At least 19 recordsLinked to original sources
PubMed2006

Ethnicity modifies the association between diabetes mellitus and ischaemic heart disease in Chinese, Malays and Asian Indians living in Singapore.

AIMS/HYPOTHESIS: The aim of the study was to determine whether the risk of ischaemic heart disease (IHD) associated with diabetes mellitus differs between ethnic groups. METHODS: Registry linkage was used to identify IHD events in 5707 Chinese, Malay and Asian Indian participants from three cross-sectional studies conducted in Singapore between the years 1984 and 1995. The study provided a median of 10.2 years of follow-up with 240 IHD events experienced. We assessed the interaction between diabetes mellitus and ethnicity in relation to the risk of IHD events using Cox proportional hazards regression. RESULTS: Diabetes mellitus was more common in Asian Indians. Furthermore, diabetes mellitus was associated with a greater risk of IHD in Asian Indians. The hazard ratio when comparing diabetes mellitus with non-diabetes mellitus was 6.41 (95% CI 5.77-7.12) in Asian Indians and 3.07 (95% CI 1.86-5.06) in Chinese (p = 0.009 for interaction). Differences in the levels of established IHD risk factors among diabetics from the three ethnic groups did not appear to explain the differences in IHD risk. CONCLUSIONS/INTERPRETATION: Asian Indians are more susceptible to the development of diabetes mellitus than Chinese and Malays. When Asian Indians do develop diabetes mellitus, the risk of IHD is higher than for Chinese and Malays. Consequently, the prevention of diabetes mellitus amongst this ethnic group is particularly important for the prevention of IHD in Asia, especially given the size of the population at risk. Elucidation of the reasons for these ethnic differences may help us understand the pathogenesis of IHD in those with diabetes mellitus.

Adult↗
PubMed2006

Treatment outcome of Singapore residents with pulmonary tuberculosis in the first year after introduction of a computerised treatment surveillance module.

INTRODUCTION: A key intervention of the Singapore Tuberculosis Elimination Programme (STEP) was the introduction in 2001 of a computerised treatment surveillance module (TSM) for the real-time monitoring of the treatment progress of the country's notified tuberculosis (TB) cases until a final outcome. We report the treatment outcome as at December 31, 2002 for the cohort of Singapore residents with new and relapsed pulmonary TB in whom treatment was commenced in 2001. METHODS: Each TB notification will activate the TSM, which requires a return on the patient's treatment progress, treatment delivery mode and the treating physician's management decision at each clinic visit to the STEP Registry until an outcome is reached. RESULTS: There were 1,354 Singapore residents with new or relapsed pulmonary TB who started treatment in 2001. Of these, 620 (45.8 percent) underwent directly-observed therapy (DOT) at their nearest polyclinic. As at December 31, 2002 , 79 percent of patients completed treatment, nine percent died (two percent from TB), nine percent interrupted treatment (they were either lost to follow-up or refused treatment), 1.8 percent were still on treatment, 0.6 percent left the country, and 0.5 percent had permanent cessation of treatment due to drug reactions. Factors associated with treatment completion were Chinese ethnicity (odds-ratio [OR] 1.5, 95 percent confidence interval [Cl] 1.1-2, p-value is 0.02), age younger than 65 years (OR 1.8, 95 percent Cl 1.3-3.0, p-value is 0.003) and the use of DOT (OR 3.1, 95 percent Cl 2.3-4.1, p-value is less than 0.05). CONCLUSION: The findings from the TSM's first year provide a baseline for future programme evaluation.

Antitubercular Agents↗
PubMed2006

Changes in the levels of major cardiovascular risk factors in the multi-ethnic population in Singapore after 12 years of a national non-communicable disease intervention programme.

INTRODUCTION: The National Healthy Lifestyle Programme, a population-wide non-communicable disease intervention programme, was started in 1992. A National Health Survey is carried out every six years to evaluate the impact of this programme on the cardiovascular risk factor profile of the resident population of Singapore. METHODS: The 2004 National Health Survey (NHS 04) was a population-based survey carried out over a period of four months from September to December 2004. A combination of disproportionate stratified sampling and systematic sampling was used to select a representative sample (n=7,078) for the survey. The reference population comprised 2.4 million multi-racial Singaporeans aged 18-69 years. Anthropometric and blood pressure measurements were carried out on all subjects and blood samples were taken for biochemical analysis. The results were compared with those of a similar survey conducted in 1998. RESULTS: A total of 4,084 Singapore residents took part in the survey, giving a response rate of 57.7 percent. The age-standardised prevalence of hypertension (greater than or equal to 140/90 mmHg) in Singapore residents aged 30-69 years decreased from 28.0 percent in 1998 to 24.0 percent (p-value is less than 0.001) in 2004. The prevalence of high total cholesterol (greater than or equal to 6.2 mmol/L) among those aged 18-69 years fell from 26.0 percent in 1998 to 18.1 percent (p-value is less than 0.001) in 2004. The prevalence of diabetes mellitus in residents aged 18-69 years in 2004 was 7.8 percent, compared to the 1998 level of 9.5 percent (p-value is less than 0.01). The level of obesity (body mass index is greater than or equal to 30 kg/sqm) increased slightly from 6.2 percent in 1998 to 6.8 percent (p-value equals 0.1627). The prevalence of daily smoking decreased from 15.0 percent in 1998 to 12.5 percent in 2004 (p-value is less than 0.001), while that of regular exercise increased from 17.0 percent to 25.0 percent (p-value is less than 0.001). Ethnic differences in the prevalence of diabetes mellitus, hypertension, hypercholesterolaemia, and exercise were observed. CONCLUSION: The NHS 04 results suggest that the National Healthy Lifestyle Programme significantly decreased daily smoking, high blood cholesterol and hypertension, and increased regular exercise over 1998 levels. The results also suggest that the programme stabilised the prevalence of obesity and diabetes mellitus.

Adolescent↗
PubMed2005

Public health measures implemented during the SARS outbreak in Singapore, 2003.

The SARS outbreak hit Singapore between March and May 2003. Public health control measures were applied along three fronts; prevention and control within healthcare settings, community and at the borders. Nosocomial spread composed majority of SARS cases in Singapore. To prevent infection within healthcare facilities, cases were centralized in a SARS-designated hospital, a no-visitors rule was applied and movement of patients and healthcare staff were restricted. For triaging purposes, fever clinics were established. A dedicated ambulance service was used to transport possible cases to the SARS-designated hospital. Hospitals were surveyed for fever clusters. The challenge was to identify cases with atypical presentation. Effective and safe discharge criteria were established from the lessons learnt. To prevent community spread, contacts of cases were stringently traced, quarantined in their homes and monitored daily. For prompt identification of a case and to reduce the time between onset of symptoms and isolation, the Infectious Diseases Act was amended. A large wholesale market closure resulted in massive quarantine thereby limiting the spread of infection. A mass education campaign was implemented in order to educate and raise awareness of the public. At all air, sea and land points-of-entry, exit and entry screening took place that resulted in zero importation and exportation of SARS cases after implementation of screening. Coordinated effort of the cross sectional inter-ministerial collaboration and strong coordination by the Task Force and commitment from different professionals made it possible to conquer the disease.

Contact Tracing↗
PubMed2005

Measurable predictive factors for progression to AIDS among HIV-infected patients in Singapore.

INTRODUCTION: This study identifies measurable factors at the time of diagnosis that predict the progression to Acquired Immunodeficiency Syndrome (AIDS) among Human Immunodeficiency Virus (HIV)-infected patients in Singapore. MATERIALS AND METHODS: We carried out a retrospective study of 790 HIV-infected patients from 16 May 1985 to 31 December 2001. The end-point was the onset of AIDS-defining illness listed in the 1987 and 1991 revised Centers for Disease Control and Prevention criteria, but excluded CD4 cell counts as a criterion. Using the Kaplan-Meier method, AIDS-free survival curves were plotted for age groups at diagnosis, baseline CD4 counts and periods for utilisation of antiretroviral treatment. A Cox regression model was constructed to determine independent predictors of disease progression. RESULTS: Univariate analysis showed that patients of older age at diagnosis had a significantly higher risk of progression compared to younger patients, and patients with higher baseline CD4 cell counts had a lower risk of progression to AIDS. Adjusting for the simultaneous influence of several covariates on the rate of HIV progression to AIDS, multivariate analysis using the Cox model showed a significantly higher risk of progression for older patients at diagnosis, and the progressive lowering of risk with increasing baseline CD4 cell counts. CONCLUSIONS: This study found older age at diagnosis and baseline CD4 cell counts to be measurable predictors for HIV progression to AIDS at time of diagnosis. Identification of these risk factors enables physicians to provide counselling and advice, and to start appropriate treatment early. This could lower the risk of progression and improve survival.

Acquired Immunodeficiency Syndrome↗
PubMed2005

Birth defects in Singapore: 1994-2000.

INTRODUCTION: To study characteristics of birth defect cases among live births, stillbirths and abortions in Singapore between 1994 and 2000. METHODS: Index cases for the National Birth Defects Registry (NBDR) were obtained from all neonatal nurseries in Singapore, all hospital discharge summaries, cytogenetic and pathology reports from all pathology laboratories in Singapore, and from the compulsory reporting of all termination of pregnancy cases and stillbirths delivered. Further information was obtained from case notes retrieved from the medical record offices, antenatal clinics, cytogenetic laboratories, pathology departments and the Registry of Births and Deaths. The notified cases (live births, stillbirths and abortions) between 1994 and 2000 were extracted from the NBDR and analysed with regard to ethnicity, maternal age, trend over the seven years and types of birth defects using the British Paediatric Association Classification. RESULTS: Between 1994 and 2000, a total of 7,870 cases (6,278 births and 1,592 abortuses) were notified, giving a rate of 23.99 birth defect cases per 1000 live births. There was a decreasing trend in birth defect incidence (19.76 to 16.85 per 1,000 live births) among live births and stillbirths and an increasing trend of abortion (3.25 to 7.57 per 1,000 live births) for birth defects. Malays had a higher rate of congenital defects at birth (24.4/1,000 live births) compared to Chinese (18.4/1,000 births). The 25-29 years age group had the lowest overall rate (22.6/1,000 live births) compared to the 19 years and below group at 31.6/1,000 live births and the 45-49 years group at 126.6/1,000 live births. The five most common groups of anomalies (per 1,000 live births) were those of heart (9.07), musculoskeletal (4.98), chromosomal (4.35), urinary (3.12) and nervous systems (2.90). The five most common aborted anomalies (per 1,000 live births) were those of chromosomal (2.40), nervous (1.23), heart (0.95), musculoskeletal (0.85) and urinary systems (0.36). CONCLUSION: There was an increasing trend of abortion for birth defects, accompanied by a falling trend in the congenital anomalies of live births. Both extremes of maternal age were at higher risk of non-chromosomal birth defects while advanced maternal age was at higher risk of chromosomal defects.

Adolescent↗
PubMed2004

Oyster-associated outbreaks of Norovirus gastroenteritis in Singapore.

Outbreaks of gastroenteritis associated with the consumption of raw imported half-shelled frozen oysters occurred in Singapore between 16 Dec 2003 and 04 Jan 2004. A total of 305 cases were reported with clinical symptoms of diarrhoea (94%), abdominal cramps (72%), vomiting (69%) and fever (54%). The median incubation period was 30.8h and the duration of illness was 2-3 days. The overall relative risk of oyster consumption was 14.1 (95% CI: 8.3-24.0, P<0.001). Stool and oyster samples tested negative for common bacterial pathogens, including Vibrio parahaemolyticus. However, stool samples were positive for the presence of Norovirus group II RNA via RT PCR while oyster samples indicated the presence of Norovirus particles by electron microscopy. The clinical and epidemiological features were suggestive of Norovirus gastroenteritis and were subsequently confirmed by laboratory tests of stools and implicated oysters. Steps have been taken to ensure that food outlets do not thaw frozen oysters and serve them raw.

Adolescent↗
PubMed2004

The lipoprotein lipase S447X polymorphism and plasma lipids: interactions with APOE polymorphisms, smoking, and alcohol consumption.

We studied 4,058 subjects from a representative sample of the Singapore population 1) to determine the association between the S447X polymorphism at the LPL locus and serum lipid concentration in Chinese, Malays, and Asian Indians living in Singapore and 2) to explore any interactions with apolipoprotein E (APOE) genotype, exercise, obesity, cigarette smoking, and alcohol intake. Information on obesity, lifestyle factors (including smoking, alcohol consumption, and exercise frequency), glucose tolerance, and fasting lipids was obtained. Male and female carriers of the X447 allele had lower serum triglyceride concentrations and higher HDL cholesterol (HDL-C) concentrations. The association between the X447 allele and serum HDL-C concentration was modulated by APOE genotype in males and cigarette smoking and alcohol intake in females. The effect of the X447 allele was greatest in men who carried the E4 allele and women who smoked or consumed alcohol. The X447 allele at the LPL locus is common and associated with a less atherogenic lipid profile in Asian populations. Interactions with APOE genotype, cigarette smoking, and alcohol intake reinforce the importance of examining genetic associations, such as this one, in the context of the population of interest.

Adult↗
PubMed2004

A population-based study on the association between parental occupations and some common birth defects in singapore (1994-1998).

We sought to study the association between some common birth defects and parental occupations. The live births and congenital malformation born between January 1994 and December 1998 were obtained from the Singapore National Registry of Births and Deaths (the National Birth Defect Registry). The prevalence of overall birth defects among Singapore live births during the study period is 13.9 per 1,000 live births. The most frequent single coding defects were "bulbus cordis anomalies and anomalies of cardiac septal closure (BCA)," "congenital anomalies of urinary system (CUS)," "cleft palate and cleft lip (CPL)," and "certain congenital musculoskeletal deformities (CMD)." Using the "Legislators, Senior Officers & Managers" as reference and adjusting for possible confounders, there were significant associations for: (1) paternal "clerical workers" (adjusted RR 2.25) with the BCA; (2) maternal "professionals" with CUS (adjusted risk ratio [RR] 3.58); (3) paternal "production craftsmen and related workers" with both the BCA (adjusted RR 2.04), and the CMD (adjusted RR 2.83); (4) paternal "plant and machine operators and assemblers" with the BCA (adjusted RR 2.49), and the CUS (adjusted RR 5.19), and the CMD (adjusted RR 3.01). Paternal rather than maternal exposure might be more important in the causation of some common birth defects in Singapore.

Abnormalities, Multiple↗
PubMed2004

Ethnic variations in female vulnerability after an acute coronary event.

OBJECTIVE: To determine the ethnic variation of short and long term female vulnerability after an acute coronary event in a population of Chinese, Indians, and Malays. DESIGN: Population based registry. PATIENTS: Residents of Singapore between the ages of 20-64 years with coronary events. Case identification and classification procedures were modified from the MONICA (monitoring trends and determinants in cardiovascular disease) project. MAIN OUTCOME MEASURES: Adjusted 28 day case fatality and long term mortality. RESULTS: From 1991 to 1999, there were 16 320 acute coronary events, including 3497 women. Age adjusted 28 day case fatality was greater in women (51.5% v 38.6%, p < 0.001), with a larger sex difference evident among younger Malay patients. This inequality between the sexes was observed in both the pre-hospitalisation and post-admission periods. Among hospitalised patients, women were older, were less likely to have suffered from a previous Q wave or anterior wall myocardial infarction, and had lower peak creatine kinase concentrations. Case fatality was higher among women, with adjusted hazard ratios of 1.64 (95% confidence interval (CI) 1.43 to 1.88) and 1.50 (95% CI 1.37 to 1.64) for 28 day and mean four year follow up periods. There were significant interactions of sex and age with ethnic group (p = 0.017). The adjusted hazards for mortality among Chinese, Indian, and Malay women versus men were 1.30, 1.71, and 1.96, respectively. The excess mortality among women diminished with age. CONCLUSION: In this multiethnic population, both pre-hospitalisation and post-admission case fatality rates were substantially higher among women. The sex discrepancy in long term mortality was greatest among Malays and in the younger age groups.

Acute Disease↗
PubMed2003

APOE polymorphism and lipid profile in three ethnic groups in the Singapore population.

BACKGROUND: Serum lipid concentrations are modulated by environmental factors such as exercise, alcohol intake, smoking, obesity and dietary intake and genetic factors. Polymorphisms at the Apolipoprotein E (APOE) locus have consistently shown a significant association with total and LDL-cholesterol (LDL-C). However, their impact on HDL-cholesterol (HDL-C) may be population dependent. Having three major ethnic groups within a similar social environment allows us to study the role of genetics and their interactions with lifestyle factors on the serum lipid profile and coronary risk in Asians. METHODS: This study included 1740 males (1146 Chinese, 327 Malays and 267 Asian Indians) and 1950 females (1329 Chinese, 360 Malays and 261 Asian Indians) with complete data on anthropometric indices, fasting lipids, smoking status, alcohol consumption, exercise frequency and genotype at the APOE locus. RESULTS: Malays and Asian Indians were more obese compared with the Chinese. Smoking was uncommon in all females but Malay males had significantly higher prevalence of smokers. Malays had the highest LDL-C whilst Indians had the lowest HDL-C, The epsilon 3 allele was the most frequent allele in all three ethnic groups. Malays had the highest frequency of epsilon 4 (0.180 and 0.152) compared with Chinese (0.085 and 0.087) and Indians (0.108 and 0.075) in males and females, respectively. The epsilon 2 allele was the least common in Asian Indians. Total cholesterol (TC) and LDL-C was highest in epsilon 4 carriers and lowest in epsilon 2 carriers. The reverse was seen in HDL-C with the highest levels seen in epsilon 2 subjects. The association between ethnic group and HDL-C differed according to APOE genotype and gender. Asian Indians had the lowest HDL-C for each APOE genotype except in Asian Indian males with epsilon 2, where HDL-C concentrations were intermediate between Chinese and Malays. CONCLUSION: Ethnic differences in lipid profile could be explained in part by the higher prevalence of epsilon 4 in the Malays. Ethnicity may influence the association between APOE genotypes and HDL-C. APOE genotype showed no correlation with HDL-C in Malay males whereas the association in Asian Indians was particularly marked. Further studies of interactions between genes and environmental factors will contribute to the understanding of differences of coronary risk amongst ethnic groups.

Alcohol Drinking↗
PubMed2003

The TaqIB and -629C>A polymorphisms at the cholesteryl ester transfer protein locus: associations with lipid levels in a multiethnic population. The 1998 Singapore National Health Survey.

The Singapore population comprises Chinese, Malays and Asian Indians. Within this population, Asian Indians have the highest rates of coronary heart disease, whereas Chinese have the lowest. Conversely, Indians have the lowest high-density lipoprotein cholesterol (HDL-C) concentrations, followed by Malays and Chinese. We studied the TaqIB and -629C>A polymorphisms at the CETP locus in 1300 Chinese, 364 Malay and 282 Asian Indian men, and in 1558 Chinese, 397 Malay and 306 Asian Indian women, to determine whether these polymorphisms are responsible for the ethnic difference in HDL-C concentration. The frequency of the B2 allele in Chinese, Malays and Indians was 0.384, 0.339 and 0.449 in men, and 0.379, 0.329 and 0.415 in women, respectively (p < 0.001). For the A-629 allele, the relative frequencies were 0.477, 0.423 and 0.592 in men and 0.486, 0.416 and 0.575 in women (p < 0.001). The two polymorphisms were in linkage disequilibrium (D / Dmax= 0.9772, p < 0.00001). The B2 and the A-629 alleles were associated with increased HDL-C concentrations in a dose-dependent manner. The B2 allele continued to show an association with HDL-C concentration, even after controlling for the genotype at position -629. Dietary cholesterol showed a significant interaction with the TaqIB polymorphism in determining HDL-C concentrations in Indians and Malays, but not in Chinese. In conclusion, the high frequencies of these polymorphisms in Asian Indians could not explain the observed ethnic differences in HDL-C concentration. Moreover, we observed an ethnic-specific interaction among dietary cholesterol, the TaqIB polymorphism and HDL-C concentrations.

Alcohol Drinking↗
PubMed2003

Parental occupations and other risk factors associated with nonchromosomal single, chromosomal single, and multiple birth defects: a population-based study in Singapore from 1994 to 1998.

OBJECTIVE: The purpose of this study was to evaluate the association between the prevalence of birth defects among maternal and paternal occupation groups in Singapore for live births between January 1, 1994, and December 31, 1998, and to determine whether there are certain demographic risk factors and maternal and/or paternal occupation groups that are associated with an increased risk for birth defects versus chromosomal single birth defect, nonchromosomal single birth defect, and multiple birth defects. STUDY DESIGN: This was a retrospective study. Information on live births (Singapore National Registry of Births and Deaths) and birth defect cases (National Birth Defects Register) were studied. Other information included the mother's date of birth, ethnic group, highest educational qualification, and the occupation of the mother and the father. Cox regression analysis was used to determine whether certain demographic and occupational factors were associated with the three groups of birth defects. RESULTS: Of a total of 237,755 live births, there were 3276 birth defect cases (nonchromosomal single birth defect, 1869 cases; chromosomal single birth defect, 197 cases; and multiple birth defects, 1210 cases). Increased risks for all types of birth defects were observed with advancing gestational age. Occurrence of nonchromosomal single birth defect and multiple birth defects were significantly higher for multiple births compared to singleton births. Significant associations were found with the use of "legislators, senior officers, and managers" as reference: Maternal occupation of "cleaners, laborers, and related workers" with chromosomal single birth defect anomalies (adjusted risk ratio, 4.86; 95% CI, 1.07-22.14); paternal occupation of "plant and machine operators and assemblers" (adjusted risk ratio, 1.50; 95% CI, 1.14-1.98) with nonchromosomal single birth defect; "production craftsmen and related workers" and "cleaners and laborers and related workers" with nonchromosomal single birth defect (adjusted risk ratio, 1.42; 95% CI, 1.10-1.82; and adjusted risk ratio, 1.43; 95% CI, 1.07-1.91 respectively); and multiple birth defects (adjusted risk ratio, 1.42; 95% CI, 1.03-1.94; and adjusted risk ratio, 1.47; 95% CI, 1.03-2.09, respectively). CONCLUSION: Maternal delivery age is an important risk factor for all birth defects. Mothers and fathers who work as "cleaners and laborers and related workers" appear to have a higher risk of giving birth to children with chromosomal single birth defect and nonchromosomal single birth defect and multiple birth defects, respectively. Further in-depth study would be needed to confirm these observations.

Abnormalities, Multiple↗
PubMed2002

Elevated body fat percentage and cardiovascular risks at low body mass index levels among Singaporean Chinese, Malays and Indians.

The aim of this study was to investigate the relationship between body mass index (BMI) and body fat percentage (BF%) in Singaporean Chinese, Malays and Indians, and to determine the risk for selected comorbidities at various BMI categories and abdominal fat distributions, as assessed by waist circumference (WC). The study was a cross-sectional (population) design. In total, 4723 subjects participated in the National Health Survey of 1998 in which the risks were investigated. A selected subsample of 291 subjects participated in a detailed body composition study, where weight, height and WC were measured, as were blood pressure, total and high-density lipoprotein (HDL) cholesterol, serum triglycerides and fasting glucose. In the subsample, BF% was determined by means of a chemical four-compartment model. At any given BF% the BMI of Singaporeans was about 3 kg m(-2) lower than that of Caucasians. There were slight differences in the BF%/BMI relationship between the three ethnic groups. For all the ethnic groups, it was found that at low categories of BMI (between 22 and 24 kg m(-2)) and WC (between 75 and 80cm for women and between 80 and 85 cm for men), the absolute risks for having at least one of the aforementioned risk factors were high, ranging from 41 to 81%. At these same categories the relative risks were significantly higher compared to the reference category, odds ratios ranging from 1.97-4.38. These categories of BMI and WC were all far below the cut-off values of BMI and WC as currently recommended by the World Health Organization (WHO). The data from the current study, which includes evidence that not only risk factors, but also BF% are elevated at low BMI values, presents a strong case for lowering the BMI cut-off value for overweight and obesity among Singaporeans, from 25 kg m(-2) and 30 kg m(-2) to 23 kg m(-2) and 27 kg m(-2), respectively.

Adipose Tissue↗
PubMed2002

Seroprevalence of IgG antibodies against Chlamydia pneumoniae in Chinese, Malays and Asian Indians in Singapore.

BACKGROUND: Chlamydia pneumoniae, a bacterium that causes respiratory infections, is probably under-diagnosed. There is also interest in its possible role in the aetiology of coronary heart disease. This is the first population-based seroprevalence survey of C. pneumoniae infection in Singapore. METHODS: A random sample of 1,068 people aged 18-69 years was selected from the participants of the Singapore National Health Survey conducted in 1998. Sera and data on certain clinical measurements and conditions had been collected. IgG antibodies for C. pneumoniae were detected using an indirect microimmunofluorescence test and positivity graded. Seropositivity was defined as IgG titre >/=1:16. RESULTS: There were no statistically significant differences in the prevalence rates of seropositivity to C. pneumoniae for age group 18-69 years among the three ethnic groups, i.e. Chinese (males 76.7%, females 68.3%), Malays (males 75.4%, females 59.1%), and Asian Indians (males 74.6%, females 59.4%). The seropositivity rate for people aged 18-69 years in Singapore was 75.0% for males and 65.5% for females (difference of 9.5%, P < 0.001). In both genders combined, seropositivity increased from 46.5% in the age group 18-29 to reach a plateau of 78.9% in the age group 40-49, which remained stable to 60-69 years. There was no association of seropositivity with smoking, diabetes mellitus, hypertension or body mass index after adjustment for age and gender. CONCLUSION: The high prevalence rates in our study population and the higher rate in males compared to females are consistent with studies from other parts of the world. No significant difference in prevalence rates was observed among Chinese, Malays and Indians. The pattern of rising and levelling off of seropositivity with age suggests that C. pneumoniae infection occurs early in life, and in older ages the high level of seropositivity is probably maintained by re-infections or chronic infections. Chlamydia pneumoniae infection was not found to be associated with the cardiovascular risk factors examined.

Adolescent↗
PubMed2002

Prevalence of birth defects and parental work in Singapore live births from 1994 to 1998: a population-based study.

The aims of the study were to assess the prevalence of birth defects (BDs) among different occupational groups and non-working parents, and to identify possible risk factors associated with BDs in Singapore live births born between 1 January 1994 and 31 December 1998. To do this, information on live births (from the Singapore National Registry of Births and Deaths) and BD cases [from the National Birth Defects Register (NBDR)] was obtained from 1 January 1994 to 31 December 1998. There were a total of 237 755 live births in Singapore between 1 January 1994 and 31 December 1998. Over the same period, 3293 cases of BDs were reported to the NBDR, giving an overall rate of 13.9 per 1000 live births. A downward trend with time was noted. Of the live born with BDs in this series, 36.7% presented with multiple anomalies. The overall occurrence of malformation (per 1000 live births) among working versus non-working mothers was 13.4 versus 14.2, respectively, and 13.8 for working fathers compared with 16.8 for non-working fathers. Parents in the occupational group 'Legislators, Senior Officers & Managers' had the lowest prevalence rates of congenital anomalies (9.4 per 1000 for mothers and 10.3 per 1000 for fathers), while the 'Agricultural & Fishery Workers' had the highest rates (40.0 per 1000 for mothers and 23.4 per 1000 for fathers). However, the very small number of workers in this latter group makes the rate unreliable. The prevalence of BDs in Singapore is comparable to those in other countries. Parental work per se is not correlated with BDs.

Adult↗
PubMed2002

Birth prevalence of Down syndrome in Singapore from 1993 to 1998.

OBJECTIVE: To examine the livebirth prevalence rate of Down Syndrome in Singapore from 1993 to 1998. DESIGN: Index cases for the National Birth Defects Register were obtained from all neonatal nurseries in Singapore, all hospital discharge summaries, cytogenetic and pathology reports from all pathology laboratories in Singapore and from the compulsory reporting of all termination of pregnancy cases and stillbirths delivered. SETTING: Information for the Register was obtained from case notes retrieved from the medical record offices, antenatal clinics, cytogenetic laboratories, pathology departments and the Registry of Births and Deaths. SUBJECTS: All foetuses with Trisomy 21 diagnosed prenatally together with livebirths and stillbirths with Down Syndrome diagnosed at or after birth were identified from the Registry database. MAIN OUTCOME MEASURES: Prevalence of Down Syndrome RESULTS: From 1993 to 1998, there were 295 Down Syndrome livebirths, four stillbirths and 197 Down Syndrome foetuses aborted. There has been an increasing number of Down Syndrome foetuses diagnosed antenatally ending in termination and this is accompanied by a falling trend in the Down Syndrome livebirth rate in the same years from 1.17 to 0.89 per 1000 total live births. This is despite an expected increase in Down Syndrome livebirth rate obtained by modelling maternal Down Syndrome age-related risks on the maternal age distribution over the years. CONCLUSIONS: The livebirth prevalence of Down Syndrome in Singapore has fallen over the years from 1.17/1000 livebirths in 1993 to 0.89/1000 livebirths in 1998 due to antenatal diagnosis and selective termination.

Abortion, Induced↗