Use of contraceptives by some selected characteristics was studied for married women in the reproductive age range (MWRA) in three south‐east Asian countries. The data were obtained from each country's national family planning/fertility survey conducted around the mid‐seventies. Only the gross relationship between each of the selected characteristics and contraceptive use was compared. The proportion of MWRA using contraceptives for Singapore was almost twice as high as the corresponding proportions for Peninsular Malaysia and Thailand. The pattern of contraceptive use was largely similar for Thailand and Malaysia but different from Singapore. The differences were largely attributed to the absence of a large rural population in Singapore, the apparently greater tendency of women in Singapore to use reversible contraceptive methods for birth spacing and the easier access by women to family planning information and services, particularly sterilisation, than in Peninsular Malaysia and Thailand.
General life tables for the 1990 Singapore resident population are given in this paper. Analyses were carried out separately for males and females for all ethnic groups as well as for Chinese, Malays and Indians. Average fractions of the last age interval lived were used to give a more precise derivation of the life table death rates from their corresponding age-specific death rates. The results show that in 1990, Singapore males had achieved a life expectancy at birth of 73.7 years while the females had attained a level of 78.6 years. These levels were comparable to those of many developed countries. Other interesting features include higher differentials in the life expectancies between sexes among the Chinese and the Indians taking over the Malays for second placing in terms of life expectancy at birth for both sexes. As a result, the Indians registered a 12% gain in life expectancy at birth for males for the decade 1980 to 1990, compared to only 7.1% for Chinese and 4.4% for Malays as well as nearly 10% for females compared to only 6.2% for Chinese and 6.3% for Malays. A subsequent paper will highlight the results of multiple-decrement life table analyses which will summarise the mortality of the 1990 Singapore resident population for various component causes of death rather than for all causes combined.
In this study whole blood cholinesterase activities were determined (tintometric method) of agricultural pesticide users exposed to organophosphorus compounds in Indonesia, Malaysia, Sri Lanka and Thailand. Analysis of the data demonstrated a universal relationship between cholinesterase levels and the time between the last exposure to organophosphorus compounds and the day of blood collection for cholinesterase determination. It is suggested that it takes approximately 5 days before whole blood cholinesterase levels revert to their normal values. No relationship between whole blood cholinesterase levels and the sex of pesticide users was demonstrated except in Sri Lanka where female sprayers had lower values. It is suggested that these lower values are associated with the anaemic status of female agricultural workers. No relationship between whole blood cholinesterase level and age was demonstrated. The measurement of pre-exposure cholinesterase values is essential for comparison of values after pesticide application.
A random sample of 23 591 single livebirths was drawn from the Singapore Registry for 1967-1974, and information extracted from the birth certificates. The proportion of low birthweight infants (2500 g or less) fell markedly from 9.1% in 1967 to 5.7% in 1974, which has not been the finding in other studies. Variation in the proportions of low birthweight infants by sex, maternal age, parity, and social class, are broadly in agreement with other studies. Indians were found to have significantly smaller babies (mean weight of 3020 g) with a higher proportion of low birthweight ones (11.5%) than the Malays (3080 g and 8.1%) and the Chinese (3130 g and 6.1%). This is despite similar distributions of gestational age, and for term babies the differences in low birthweight proportions are highly significant with Chinese 5.0%, Malays 6.5%, and Indians 9.8%. The reasons for this are discussed with the implication that lower birthweights in Indians are to some extent of ethnic/genetic origin.
All singleton live births occurring in Singapore in the three years 1981-3 were computed, and birthweight was examined in the different ethnic groups (Chinese, Malay, and Indian). Overall the proportions of babies of very low birthweight (less than 1500 g) and low birthweight (less than 2500 g) were: Chinese 0.3% and 6.1%, Malays 0.4% and 8.5%, and Indians 0.5% and 10.0%. The important finding was that in all gestational periods and virtually all maternal age and live birth order groups Indians had the highest proportion of very low and low birthweight babies. However for prematurity Indians at 6.7% had a higher rate than Chinese (5.1%) but lower than Malays (9.9%). Likewise for neonatal mortality Indians at 8.7 per 1000 live births were between Chinese (7.1) and Malays (9.1). The evidence seems to indicate that the reason for Indians having a higher proportion of low birthweight babies is partly ethnic/genetic, and the cut-off point of 2500 g should perhaps be lowered for babies from the Indian subcontinent when international comparisons are being made.
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.
The study investigated the extent of acute pesticide poisoning in selected agricultural communities in Indonesia, Malaysia, Sri Lanka and Thailand, as well as the contributing factors, because it is believed that this type of poisoning is a major problem in developing countries, but not in the industrialized countries, despite their extensive use of pesticides. The study confirmed the existence of this problem, which was found to be due to inadequate knowledge of the safe practices in the use of pesticides among users and to the lack of suitable protective clothing for use by agricultural workers in hot and humid climates.
A systematic collection of fetal morphometric measurements was started seven years ago in 1987 with the prospective entry of data into personal computer-based stations in the Department of Obstetrics and Gynaecology, Singapore General Hospital. A cross-sectional study was done, comparing 2392 Chinese fetuses with 2117 Malay fetuses and 459 Indian fetuses from 18 to 40 weeks. The mean values of the head circumference (HC), abdominal circumference (AC) and femur length (FL) of the 3 ethnic groups were analysed. There were no statistical significant differences in the head circumference and abdominal circumference of Chinese, Malay and Indian fetuses in Singapore. The Chinese and Malay fetal femur length appeared similar but were apparently shorter than the Indian femur length. Nomograms of head circumference, abdominal circumference and femur length were constructed for application to fetuses of all 3 ethnic groups.
This study was a cross-sectional random survey of the whole of Singapore, based on 2143 subjects (aged 18-69 years, response rate 60.3%). The presence of corneal arcus was determined by a doctor using the naked eye in good light. Cardiovascular risk factors were measured by standardized techniques. The prevalence rates overall of corneal arcus were: 18-29 years (males 0.5%, females 0.3%), 30-49 years (males 18.1%, females 13.3%) and 50-69 years (males 70.7%, females 55.3%). In the 30-49 age group, people with arcus had higher serum low density lipoprotein (LDL) cholesterol concentrations than people without arcus, the mean differences being, males 0.31 mmol/l (P = 0.040) and females 0.62 mmol/l (P less than 0.001) with an increased likelihood of having values greater than 5.5.mmol/l of males 1.8 (95% confidence interval (95% CI): 1.0-3.4) and females 2.6 (95% CI: 1.4-4.8). There were no significant differences for LDL-cholesterol in the 50-69 age group. Arcus was weakly associated with fasting plasma glucose in the 30-49 age group. Arcus was not associated with serum high density lipoprotein (HDL) cholesterol, serum fasting triglyceride, blood pressure and cigarette smoking. It is concluded that while corneal arcus is primarily an age-related change, its formation is accelerated by high serum LDL-cholesterol so that in people under 50 years it is a marker for the condition.
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 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.
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.
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.