KEY MESSAGES: A number of findings with a translational and clinical focus have already emerged. In the mothers, we found that changes and differences in food consumption varied across ethnic groups, with persistence of traditional beliefs, during pregnancy and the postpartum period. During pregnancy, higher maternal glucose levels, even in the absence of gestational diabetes mellitus, had graded relations with infant adiposity. Relations between maternal emotional health and birth outcomes and neurodevelopment have been identified. Genotype (25%) and in particular gene × environment interactions (75%) shape interindividual variations in the DNA methylome at birth. The complex effects of fixed genetic variations and different in utero environments can influence the epigenetic status at birth and the later-life phenotype.
CONCLUSIONS: The richness of the clinical data in 3 ethnicities, the extent of the biospecimen collection, and the extensive infancy and preschool follow-up have allowed us to study the biological pathways that link fetal development to health outcomes. In the coming years, more sophisticated analyses of epigenotype-phenotype relationships will become possible as the children grow and develop. Our studies will lead to the development of clinical and population-based interventions to reduce the burden of NCD.
MATERIALS AND METHODS: This was a retrospective descriptive study. We identified 1041 patients (810 Chinese, 139 Malays, 92 Indians) without previous history of cardiovascular disease who underwent cardiac computed tomography for atypical chest pain evaluation. A cardiologist, who was blinded to the patients' clinical demographics, reviewed all scans. We retrospectively analysed all their case records.
RESULTS: Overall, Malays were most likely to be active smokers (P = 0.02), Indians had the highest prevalence of diabetes mellitus (P = 0.01) and Chinese had the highest mean age (P <0.0001). The overall prevalence of patients with non-calcified plaques as the only manifestation of sub-clinical coronary artery disease was 2.1%. There was no significant difference in the prevalence of CAC, mean CAC score or prevalence of non-calcified plaques among the 3 ethnic groups. Active smoking, age and hypertension were independent predictors of CAC. Non-calcified plaques were positively associated with male gender, age, dyslipidaemia and diabetes mellitus.
CONCLUSION: The higher MI rates in Malays and Indians in Singapore cannot be explained by any difference in CAC or non-calcified plaque. More research with prospective follow-up of larger patient populations is necessary to establish if ethnic-specific calibration of CAC measures is needed to adjust for differences among ethnic groups.
MATERIALS AND METHODS: Eight hundred and twenty-eight subjects (404 PD patients, and 424 age and gender-matched control subjects without neurological disorders) were recruited. Genotyping was done by Taqman® allelic discrimination assay on an Applied Biosystems 7500 Fast Real-Time PCR machine.
RESULTS: The heterozygous A419V genotype was found in only 1 patient with PD, compared to 3 in the control group (0.4% vs 1.3%), giving an odds ratio of 0.35 (95% confidence interval (CI), 0.01 to 3.79; P = 0.624).
CONCLUSION: A419V is not an important LRRK2 risk variant in our Asian cohort of patients with PD. Our data are further supported by a literature review which showed that 4 out of 6 published studies reported a negative association of this variant in PD.
MATERIALS AND METHODS: This was a cross-sectional, populationbased, epidemiological study of adult Singapore residents aged 18 years and above. The subjects were randomly selected using a disproportionate stratified sampling method. The diagnoses of selected mental disorders including major depressive disorder (MDD), dysthymia, bipolar (bipolar I & II) disorders, generalised anxiety disorder (GAD), obsessive compulsive disorder (OCD), alcohol abuse and alcohol dependence were established using the Composite International Diagnostic Interview, which is a fully structured diagnostic instrument that assesses lifetime and 12-month prevalence of mental disorders.
RESULTS: Among the 6616 respondents (response rate of 75.9%), 12.0% had at least one lifetime affective, anxiety, or alcohol use disorders. The lifetime prevalence of MDD was 5.8% and that of bipolar disorder was 1.2%. The combined lifetime prevalence of the 2 anxiety disorders, GAD and OCD was 3.6%, with the latter being more common than GAD (0.9% and 3.0% respectively). The lifetime prevalence of alcohol abuse and dependence were found to be 3.1% and 0.5% respectively. Age, gender, ethnicity, marital status and chronic physical illnesses were all significant correlates of mental disorders.
CONCLUSION: The identified associated factors would help guide resource allocation, policy formulation and programme development in Singapore.
MATERIALS AND METHODS: A total of 292 subjects were recruited, comprising 150 ischaemic stroke patients and 142 control subjects who were age and sex matched. Plasma homocysteine, serum folate and vitamin B12 were measured in all subjects. Genotyping was carried out using PCR-RFLP.
RESULTS: The homocysteine levels were significantly higher (P = 0.001) in the stroke group (11.35 ± 2.75 μmol/L) compared to the control group (10.38 ± 2.79 μmol/L). The MTHFR C677T genotype distribution for the stroke group was 46%, 40% and 14%, respectively for CC, CT and TT genotypes and 59.9%, 33.8% and 6.3%, respectively for the control group. The genotype and allelic frequencies were significantly different between the 2 groups, with P = 0.02 and P = 0.004 respectively. No significant difference was seen in the genotype distribution inter-ethnically. An increasing tHcy was seen with every additional T allele, and the differences in the tHcy for the different genotypes were significant in both the control (P <0.001) and stroke groups (P <0.001).
CONCLUSION: This study shows that TT genotype of the methylenetetrahydrofolate reductase C677T polymorphic gene is an important determinant for homocysteine levels in Malaysian ischaemic stroke patients.
MATERIALS AND METHODS: This was a prospective study conducted at a tertiary hospital in Singapore. Healthy pregnant women with the intention to breastfeed were recruited. Diet profile was studied using a standard validated 3-day food diary. Breast milk was collected from mothers at 1 to 2 weeks and 6 to 8 weeks postnatally. Agilent gas chromatograph (6870N) equipped with a mass spectrometer (5975) and an automatic liquid sampler (ALS) system with a split mode was used for analysis.
RESULTS: Seventy-two breast milk samples were obtained from 52 subjects. Analysis showed that breast milk ETA (Eicosatetraenoic acid) and ETA:EA (Eicosatrienoic acid) ratio were significantly different among the races (P = 0.031 and P = 0.020), with ETA being the highest among Indians and the lowest among Malays. Docosahexaenoic acid was significantly higher among Chinese compared to Indians and Malays. No difference was demonstrated in n3 and n6 levels in the food diet analysis among the 3 ethnic groups.
CONCLUSIONS: Differences exist in breast milk fatty acid composition in different ethnic groups in the same region, although no difference was demonstrated in the diet analysis. Factors other than maternal diet may play a role in breast milk fatty acid composition.
MATERIALS AND METHODS: The EQ- 5D was cross-culturally adapted and translated using an iterative process following standard guidelines. Consenting adult Malay- and Tamil-speaking subjects at a primary care facility in Singapore were interviewed using a questionnaire (including the EQ-5D, a single item assessing global health, the SF-8 and sociodemographic questions) in their respective language versions. Known-groups and convergent construct validity of the EQ-5D was investigated by testing 30 a priori hypotheses per language at attribute and overall levels.
RESULTS: Complete data were obtained for 94 Malay and 78 Indian patients (median age, 54 years and 51 years, respectively). At the attribute level, all 16 hypotheses were fulfilled with several reaching statistical significance (Malay: 4; Tamil: 5). At the overall level, 42 of 44 hypotheses related to the EQ-5D/ EQ-VAS were fulfilled (Malay: 22; Tamil: 20), with 21 reaching statistical significance (Malay: 9; Tamil: 12).
CONCLUSION: In this study among primary care patients, the Singapore Malay and Tamil EQ-5D demonstrated satisfactory known-groups and convergent validity.
MATERIALS AND METHODS: Mean SF-36 scores were calculated for 24 population subgroups (categorised by age, gender, ethnicity and questionnaire language) and for subjects with self-reported co-morbid conditions using data from a community-based survey in Singapore.
RESULTS: The English and Chinese SF-36 was completed by 4122 and 1381 subjects, respectively, 58% (n = 3188) of whom had self-reported co-morbid conditions. SF-36 scores varied in subgroups differing in age, gender and ethnicity. In general, subjects with self-reported co-morbid conditions had lower SF-36 scores than those without these conditions, the magnitude of which exceeded 20 points in several instances. A method for calculation of SF-36 scores adjusted for age, gender, ethnicity and questionnaire language is described.
CONCLUSION: We present norms for English and Chinese SF-36 versions in Singapore and describe potential uses for these data in assessing HRQOL in Singapore.
RESULTS: From 1988 to 1997, 13,048 myocardial infarct events were diagnosed with 3367 deaths. There was a 39.1% decline in mortality, with an average decline of 6.5% per year [95% confidence intervals (CI), -3.9% to -9.1%]. However, the decline in incidence was only 20.8% with an average decline of 2.4% per year (95% CI, -6.6% to -1.2%). The highest incidence and mortality rates for both genders were seen in the Indians, followed by the Malays and the Chinese.
CONCLUSION: Over 10 years, from 1988 to 1997, we documented a significant fall in mortality from MI in Singapore. There was a smaller decline in the incidence of infarction. Singapore implemented a National Healthy Lifestyle Programme in 1992 as a 10-year effort. The disparity in the incidence and mortality may suggest that a more dramatic and immediate impact has taken place in mortality through therapeutic programmes; primary preventive programmes would be more difficult to evaluate and have a more gradual impact. Only with continual accurate data collection through the whole country, over a much longer period, can the relative value of preventive and therapeutic programmes in coronary heart disease be assessed.
MATERIALS AND METHODS: The Singapore Cardiovascular Cohort Study is a longitudinal follow-up study on a general population cohort of 5920 persons drawn from 3 previous cross-sectional surveys. Morbidity and mortality from IHD and stroke were ascertained by record linkage using a unique identification number with the death registry, Singapore Myocardial Infarct Registry and in-patient discharge databases.
RESULTS: There were 193 first IHD events and 97 first strokes during 52,806 person-years of observation. The overall incidence of IHD was 3.8/1000 person-years and that of stroke was 1.8/1000 person-years. In both males and females, Indians had the highest IHD incidence, followed by Malays and then Chinese. For males after adjusting for age, Indians were 2.78 times (95% CI 1.86, 4.17; P < 0.0001) and 2.28 times (95% CI 1.34, 3.88; P = 0.002) more likely to get IHD than Chinese and Malays respectively. For females after adjusting for age, Indians were 1.97 times (95% CI 1.07, 3.63; P = 0.03) and 1.37 times (95% CI 0.67, 2.80; P = 0.39) more likely to get IHD than Chinese and Malays respectively. For stroke, male Chinese and Indians had higher incidence than Malays (though not statistically significant). However, in females, Malays had the highest incidence of stroke, being 2.57 times (95% CI 1.31, 5.05; P = 0.008) more likely to get stroke than Chinese after adjustment for age.
CONCLUSIONS: This prospective study of both mortality and morbidity has confirmed the higher risk of IHD in Indians. It has also found that Malay females have a higher incidence of stroke, which deserves further study because of its potential public health importance.