STUDY OBJECTIVE:The aim of the study was to analyse differences in mortality from the main cardiovascular diseases (ischaemic heart disease, hypertensive disease, and cerebrovascular disease) among Chinese, Malays, and Indians in Singapore.
DESIGN: The study was a survey using national death registration data in Singapore for the five years 1980 to 1984. The underlying cause of death, coded according to the ninth revision of the International Classification of Diseases, was taken for the analyses.
SETTING: The study was confined to the independent island state of Singapore, population 2.53 million (Chinese 76.5%, Malays 14.8%, Indians 6.4%, Others 2.3%). Death registration is thought to be complete.
SUBJECTS: All registered deaths in the age range 30-69 years during the study period were analysed by ethnic group.
MEASUREMENT AND MAIN RESULTS: Indians had higher mortality from ischaemic heart disease than the other ethnic groups in both sexes, with age-standardised relative risks of Indian v Chinese (males 3.8, females 3.4), Indian v Malay (males 1.9, females 1.6), and Malay v Chinese (males 2.0, females 2.2). The excess mortality in Indians declined with age. For hypertensive disease Malays had the highest mortality, with age-standardised relative risks of Malay v Chinese (males 3.4, females 4.4), Malay v Indian (males 2.0, females 2.5), and Indian v Chinese (males 1.6, females 1.6). For cerebrovascular disease there was little ethnic difference except for lower rates in Chinese females, with age-standardised relative risks of Malay v Chinese (males 1.1, females 1.9), Malay v Indian (males 1.0, females 1.1), and Indian v Chinese (males 1.1, females 1.7).
CONCLUSIONS: There are significant differences in mortality from the three main cardiovascular diseases in the different ethnic groups in Singapore.
A population based survey has measured levels of physical activity by questionnaire in persons aged 18 to 69 years in Singapore. Levels of physical activity were classified into high, medium and low based on activity in leisure and at work. The only ethnic difference was that for males a higher proportion were classified as "high" activity in Malays (24.8%) than Chinese (16.0%) and Indians (18.1%). For the overall 18 to 69 age group, it was found that for males, the proportions in the "low" category were Chinese 80%, Malays 70% and Indians 75% while for females it was 95% in all three ethnic groups. As physical activity of sufficient intensity is important in disease prevention and health promotion, more needs to be done on educating the public in Singapore about the benefits of regular exercise.
A population based cross-sectional survey has measured body mass indices (BMIs) in Singapore and compared their means and the proportions who are overweight and obese amongst Chinese, Malays and Indians. For males there was little ethnic differences; for the 18-69 age group, the age-adjusted mean BMIs being Chinese 22.3, Malays 23.1 and Indians 22.5. However for females, Malays and Indians were considerably more obese than Chinese; for the 18-69 age group the age-adjusted mean BMIs in Malays (25.1) and Indians (24.6) were significantly greater (p less than 0.001) than in Chinese (22.2). The proportions categorised as overweight or obese (BMI equal to or more than 26 in males and 25 in females) were males (Chinese 16.7%, Malays 22.4%, and Indians 14.0%) and females (Chinese 21.2%, Malays 51.5%, and Indians 42.0%). Health education on the harmful effects of obesity should be targeted especially on Malay and Indian females.
A population based survey has measured alcohol consumption by questionnaire in persons aged 18 to 69 years in Singapore. The majority were "occasional/none" drinkers, being males (Chinese 87%, Malays 99% and Indians 80%) and females (Chinese 98%, Malays 100% and Indians 100%). "Heavy" consumption was uncommon in males (Chinese 0.6%, Malays 0% and Indians 1.3%) and absent in females, while "heavy/moderate" drinking was males (Chinese 5.7%, Malays 0.5% and Indians 3.8%) and females (Chinese 0.3%, Malays 0% and Indians 0%). For males, "light" drinking was highest in Indians (15.9%), then Chinese (7.8%) and then Malays (0.5%). This survey indicates that alcohol consumption is not yet a major public health problem in Singapore.
Mortality from ischaemic heart disease in Singapore is now reaching comparability with the West. For the early 1980s, rates for Indians and Malays were higher than in U.S.A. and England and Wales and while those for Chinese were lower they were considerably higher than in Japan. In keeping with this the levels of the major risk factors in Singapore are now comparable to the West. Cigarette smoking in males is virtually the same as in Britain, while the proportion of hypertensives on medication is higher than in the West. The main cause for concern is the current high levels of serum cholesterol in Singapore and strenuous health education efforts are needed to bring about dietary changes.
A country-wide diabetic survey of the population (age 15 years and above) of Singapore shows that the prevalence of diabetes mellitus in Singapore is 1.99 percent. It is commoner in males (2.36 percent) than in females (1.64 percent). The prevalence of diabetes in the age group 15-39 years is only 0.40 percent and in the age group 40 years and older it is 5.08 percent. The prevalence of diabetes in Indians (6.07 percent) is significantly higher than that in Malays (2.43 percent) and Chinese (1.55 percent). Indian diabetics have an insignifi"cantly higher incidence of positive family of diabetes (12.7 percent) than Malays (10.9 percent) and Chinese (6.5 percent). Obesity was commoner in Malay diabetics (67.4 percent) than in Chinese diabetics (41.6 percent) and Indian diabetics (35.7 percent). The survey shows that 40.4 percent of the diabetics are known while 59.6 percent of the diabetics are newly diagnosed. The majority of the diabetics are treated with oral hypoglycaemic drugs (71.5 percent) and only 4.8 percent are receiving insulin injections. A mong the female diabetics, 63.0 percent have 4 or more pregnancies and large babies at birth are recorded in 12.3 percent. In the newly diagnosed diabetics, 64.3 percent have no symptoms. The complications of the diabetics are hypertension (26.8 percent), nephropathy (9.8 percent), retinopathy (8.5 percent), coronary heart disease (6.1 percent), skin infection (4.6 percent) and neuropathy (3.3 percent). The high prevalence of diabetes among the Indians is likely to be due to a genetic predisposition coupled with an environmental factor (obesity), although this hypothesis is not conclusively demonstrated by the present study.
225 women with diabetes in pregnancy were managed by a team of obstetricians, physicians (endocrinologists) and paediatricians from the National University of Singapore. A protocol of management was formulated and followed. The incidence of 1.1% or 1 in 90 pregnancies was found, with significantly higher incidence in Indians and lower in Malays. There were 37 established diabetics and 188 diagnosed during pregnancy. Of these (188), 74 were gestational diabetics. All the women were treated with Insulin and Diet or Diet alone. 177 (79%) were treated with Insulin and Diet. Blood sugar profiles were done for monitoring diabetic control. 72.8% of the women were between para 0 and 1 and 85.2% between the ages of 20 and 34. 72.5% of the women delivered at 38 weeks gestation or later. 48.9% went into spontaneous labour, 32.4% were induced and 18.7% had elective caesarean section. 62.2% of the women had labour of less than 12 hours. The overall caesarean section rate was 41.7%. There were 3 stillbirths and 2 neonatal deaths. The perinatal mortality rate was 2.2%. Thirteen babies had congenital malformations (5.8%). 77.8% of the babies had Apgar score of 7 or more at 5 minutes after delivery. 79.1% of the babies weighed between 2.5 kgm and 3.9 kgm. Pre-eclamptic toxaemia was the commonest complication in pregnancy followed by Urinary Tract Infection and Polyhydramnios. Postpartum complications in the mother were confined to 14 women (6.2%), and wound infection or breakdown was the commonest cause.
Singapore is a tropical island city-state with a population of 2.4178 million consisting of Chinese (76.7%), Malays (14.7%), Indians (6.4%) and other races (2.2%). A diabetic survey of the adult population, aged 15 years and above, carried out in 1975, shows that the prevalence of diabetes is 1.99%; it is higher in males (2.36%) than in females (1.64%). It occurs mainly in the age group 40 years and above (5.08%) and is uncommon in the age group 15-39 years (0.40%). In males, the highest prevalence of diabetes (7.0%) is in the age group 45-49 years while in females the highest prevalence (7.2%) is in the age group 55-59 years. 43.3% of the diabetics are of normal weight while 44.3% are overweight and 12.4% are underweight. 59.6% of the diabetics are newly diagnosed while 40.4% are known diabetics; 64.3% of the newly diagnosed diabetics have no symptoms. The prevalence of diabetes among the Indians (6.07%) is significantly higher than that in Malays (2.43%) and Chinese (1.55%). Indian diabetics have a slightly higher positive family history of diabetes (12.7%) than Malays (10.9%) and Chinese (6.5%). Obesity is commoner in Malay diabetics (64.7%) than in Chinese (41.6%) and Indians (35.7%). The possible factors leading to the significantly higher prevalence of diabetes among the Indians compared to the other ethnic groups in Singapore are discussed. It is suggested that the Indian gene is susceptible to diabetes (diabetic genotype) and increased food consumption, altered lifestyle and greater obesity leads to the expression of diabetes.(ABSTRACT TRUNCATED AT 250 WORDS)
STUDY OBJECTIVE: The aim of the study was to examine cardiovascular risk factors to see how these might explain differences in cardiovascular disease mortality among Chinese, Malays, and Indians in the Republic of Singapore.
DESIGN: The study was a population based cross sectional survey. Stratified systematic sampling of census districts, reticulated units, and houses was used. The proportions of Malay and Indian households were increased to improve statistical efficiency, since about 75% of the population is Chinese.
SETTING: Subjects were recruited from all parts of the Republic of Singapore.
SUBJECTS: 2143 subjects aged 18 to 69 years were recruited (representing 60.3% of persons approached). There were no differences in response rate between the sexes and ethnic groups.
MEASUREMENTS AND MAIN RESULTS: Data on cardiovascular risk factors were collected by questionnaire. Measurements were made of blood pressure, serum cholesterol, low and high density lipoprotein cholesterol, fasting triglycerides and plasma glucose. In males the age adjusted cigarette smoking rate was higher in Malays (53.3%) than in Chinese (37.4%) or Indians (44.5%). In both sexes, Malays had higher age adjusted mean systolic blood pressure: males 124.6 mm Hg v 121.2 mm Hg (Chinese) and 121.2 mm Hg (Indians); females 122.8 mm Hg v 117.3 mm Hg (Chinese) and 118.4 mm Hg (Indians). Serum cholesterol, low density lipoprotein cholesterol and triglyceride showed no ethnic differences. Mean high density lipoprotein cholesterol in males (age adjusted) was lower in Indians (0.69 mmol/litre) than in Chinese (0.87 mmol/litre) and Malays (0.82 mmol/litre); in females the mean value of 0.95 mmol/litre in Indians was lower than in Chinese (1.05 mmol/litre) and Malays (1.03 mmol/litre). Rank prevalence of diabetes for males was Indians (highest), Malays and then Chinese; for females it was Malays, Indians, Chinese.
CONCLUSIONS: The higher mortality from ischaemic heart disease found in Indians in Singapore cannot be explained by the major risk factors of cigarette smoking, blood pressure and serum cholesterol; lower high density lipoprotein cholesterol and higher rates of diabetes may be part of the explanation. The higher systolic blood pressures in Malays may explain their higher hypertensive disease mortality.