A total of 627 subjects comprising 455 Chinese, 127 Dravidian Indians and 45 Malays were investigated for serum Apo A-IV polymorphism. The frequency of Apo A-IV*2 was found to be significantly higher (p less than 0.001) in Indians (0.043) compared to that in the Chinese (0.010) and Malays (0.011). The frequency of A-IV*3 was found to be around 0.02 in all the ethnic groups. A low frequency of A-IV*4 (less than 0.01) was observed in the Chinese and Indians. The phenotypic distribution of Apo A-IV was at Hardy-Weinberg equilibrium in the three ethnic groups.
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.
A retrospective study on discharges of children from hospital against medical advice or at own risk (AOR) discharges was conducted at our department from March 1981 to February 1990. There were altogether 890 patients giving an average incidence of 2%/year. The racial composition comprised 62.5% Chinese, 28.5% Malay, 7.3% Indian and 1.7% others. The common reasons for AOR discharge includes: (a) Inconvenience of having the child hospitalised (18.4%). (b) Preference of being treated by the general practitioner (15%). (c) Parents think child is well (14%). (d) Preference of being treated by private specialist or other hospital (11.9%) etc. Neonate comprised 16.9%, infants (except neonates) 44%, children > 1-5 yrs 28.6%, > 5-10 yrs 7.7% and > 10 yr 1.9%. The common diagnoses of these children include gastroenteritis (13.9%), febrile fit (13%), upper respiratory tract infection (11.7%), neonatal jaundice (5.7%). In conclusion AOR discharges of children from hospital is not uncommon and more could be done to reduce the incidence.
The close epidemiological relationships between specific genital human papillomavirus (HPV) types and neoplasia of the cervix uteri have been extensively documented worldwide, including Singapore. Cervical cancer incidence rates in Singapore show variations between the major ethnic groups. To ascertain the corresponding HPV infection rates among the various races in Singapore, we analysed the cervical smears of 225 women by filter in situ DNA hybridization, and compared the data with a previous similar study. Fourteen (6.2%) individuals were HPV-positive, with HPV 16 and HPV 31 being the commonest types. No significant difference between HPV positivity rates in Chinese (5.0%) and in Malays (6.7%) was found, even though Chinese have a higher cervical cancer incidence than Malays. Furthermore, the cervical HPV carriage rate among women with normal cytology was 5.9%. In the light of reports of high genital HPV prevalence rates detected by DNA amplification, these data support the notion that HPV infection is commonly latent and requires the cooperation of other factors for cervical carcinogenesis.
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.
Data on 1800 term babies, 600 from each of the Chinese, Malay and Indian racial groups, were used to identify the factors affecting birthweight in Singapore. After adjustment for gestation, maternal height and other variables, the mean Indian birthweight was 100 g less than for the Chinese (P less than 0.001), 0.001), while the Malays averaged 33 g less than the Chinese. The shortfall in Indian birthweight is thought to be due, at least partly, to environmental factors.
Haemorrhagic fever with renal syndrome (HFRS) is caused by a group of RNA viruses within the family of Bunyaviridae known as hantaviruses. The classical, severe form of HFRS is characterized by fever, headache, abdominal and lumbar pain, proteinuria, haemorrhagic phenomena, shock and renal failure. The disease is associated with the prototype Hantaan virus and occurs in rural areas of Korea and China with Apodemus mice as reservoir hosts. A clinically less severe form of HFRS, which is caused by Seoul virus, occurs in urban areas with the house rat Rattus novegicus as the main reservoir host. The disease in nonendemic areas may be atypical and patients with symptoms the hepatitis and minimal renal involvement have been observed in Malaysia. Outbreaks of HFRS in humans involving infected laboratory rat colonies have occurred in several medical centres in various countries. Hantaviruses cause a chronic, asymptomatic infection in rodents which excrete the virus in their lungs, saliva and urine. Man becomes infected mainly by inhalation of infected droplets from healthy rodent carriers. Seroepidemiological studies using mainly the indirect immunoflourescent antibody test of sera from humans and rats showed that hantaviruses have a worldwide distribution.
A 22-year-old Malay man with recurrent hypoglycaemic fainting spells was found to have hyperinsulinism. Although the CT scan of the abdomen and arteriogram failed to demonstrate any tumour in the pancreas, three tumours were found in the body of the pancreas at laporatomy, An appraisal of the techinques currently available for diagnosis and localisation of insulinoma is presented.
This study was conducted on 506 firemen in Singapore. Interviews, pulmonary function tests and audiometry were conducted. With regard to pulmonary function, the results showed that forced vital capacity (FVC) increased up to the age of 25-30 years for both Chinese and Malays. Both FVC and forced expiratory volume in one second (FEV1.0) increased with standing height over the whole age range studied. The mean values of FVC and FEV1.0 were higher in Chinese. It was also found that the FEV1 of the subjects in the study showed a greater decline in rate with age than other workers studied by the authors previously. The hearing threshold of 83 fire fighters showed a prominent upward shift of 6-8 KHz at ages 20-30. This upward shift was more pronounced in the right ear. The implications of the findings are discussed and a comparison with results of other similar studies in other countries is made.
Blood lead levels of two ethnic groups (11 Chinese and 25 Malays) of workers in a factory manufacturing lead accumulator battery were studied. The mean adjusted (for environmental lead levels, age, exposure duration and stick-years of smoking by analysis of covariance) blood lead level of the Malays was 34.8 micrograms/dl as compared to 22.4 micrograms/dl for the Chinese. This difference was significant (p less than 0.02). Oral ingestion of lead, through eating of food with hands contaminated by lead compound, among the Malay workers was suggested as a possible cause for the difference in the mean blood lead levels. Preventive measures and recommendations to overcome the problem among this particular group of workers were discussed.
Three different ethnic groups from Singapore comprising 79 Chinese, 34 Malays and 23 Indians of Dravidian origin, were investigated for the HindIII RFLP at the DNF15S2 locus. The three populations had very similar allele frequencies and the frequency of rarer(S) allele was significantly (p less than 0.01) lower (0.21) in these ethnic groups compared to that in Caucasians (0.41). The phenotypic distributions were at Hardy-Weinberg equilibrium.
Based on data collected by the population-based Singapore Cancer Registry over the period 1968 to 1982, baseline epidemiological characteristics and incidence trends of primary liver cancer were described. This will facilitate the interpretation of future trends, especially in the light of new interventions such as hepatitis B immunisation. The primary liver cancer incidence is four times higher in males than in females, with the incidence peaked in the seventh decade. The incidence rate was higher in the Chinese than in Malays and Indians and marginally higher among foreign born than Singapore born Chinese. A general declining trend in liver cancer incidence was especially notable in the local born Chinese. Misclassification of metastatic carcinomas in the earlier years of cancer registration may have contributed to the initial higher incidence. Definitive decrease in incidence as a result of hepatitis immunisation will only be seen in another two to three decades.
Singapore is an island republic of 616 km2. Four main ethnic groups make up its population of 2.4 million; these are the Chinese, Malays, Indians and others. Singapore's successful housing, industrialization and modernization programmes have caused tremendous changes in the lifestyles and expectations of the people. This very success has rendered some traditional customs impractical and irrelevant. Older Indians and Malay women still chew betel-nut. During the Hindu Thaipusam ceremony a traditional practice of dental interest is the piercing of devotees' cheeks and tongues with slivers of silver. There is no pain, bleeding or permanent tissue damage. The Chinese pick their teeth, crack melon seeds and scrape their tongues every morning. They also drink large quantities of unsweetened tea. Yet they remain caries-prone. Singaporeans have recently adopted the practice of eating at all hours of the day and night. This may have a bearing on their future caries state. Singapore has two categories of dental practitioner: the graduate and the registered but unqualified dentist who is invariably of Chinese descent. The swaged metal crown over sound and diseased tooth structure is frequently the unfortunate trademark of the latter. Often abscesses and cysts develop beneath these crowns. Successful dental health programmes have produced a DMFT of 2.8 in 12-year-old children, which betters the DMF target of 3.0 set by WHO for the year 2000. The progressive outlook of Singaporeans may eventually reduce further the number of traditional practices which are harmful to oral health.
Consideration. is gzven to the recognition and prevention of carious types of mental retardation due to hazards of environmental origin. Observations are presented on congenital syphilis, congenital toxoplasmosis, congenital rubella, Singapore kernicterus, Japanese B encephalitis, and tuberculous meningitis. Appropriate preventiue measures have resulted in a significant reduction in Singapore of these conditions, and hence in a decreased frequency of environmentally determined mental retardation. and related disabilities.
Peripheral fibroma/fibrous epulis accounts for the great majority of localised gingival swellings as was substantiated by various reports in the literature. A study was undertaken to investigate the clinical features of a series of 204 localised fibrous gingival swellings received by the Histopathology Laboratory, Department of Oral Surgery, National University of Singapore. The female patients were more affected than the male patients and the lesions occurred predominantly among the Chinese. The lesions were mainly pedunculated and most commonly occurred in anterior maxilla. The recurrence rate was about 10.3%. In conclusion the results obtained in this study were overall in agreement with those of other authors.
Peptic ulcer occurs with different frequencies in the three main racial groups in Singapore. This study aimed firstly to determine the prevalence of Helicobacter pylori in peptic ulcer and non-ulcer dyspepsia patients of the different races and secondly, to assess the relation between H pylori, histological gastritis, patient diagnosis, and race. Gastric antral biopsy specimens from 1502 patients undergoing gastroduodenoscopy were studied and 892 (59%) were positive for H pylori. H pylori was strongly associated with gastritis: 873 of 1197 (73%) patients with gastritis were positive compared with 19 of 305 (6%) without gastritis (p less than 0.0001). The prevalences of H pylori and gastritis were similar in peptic ulcer patients of different races. Malay patients with non-ulcer dyspepsia, however, were less likely to be positive for H pylori (10 of 46 (22%] or to have antral gastritis (17 of 46 (37%] than Chinese (292 of 605 (48%) were positive for H pylori and 421 of 605 (70%) had gastritis) and Indians (35 of 61 (57%) were H pylori positive and 42 of 61 (69%) had gastritis). Patients with duodenal ulcer were more likely to be positive for H pylori than those with non-ulcer dyspepsia, even when subjects with gastritis were considered separately. While our results do not help to explain the observed racial differences in peptic ulcer frequency it may be that the pathophysiology of non-ulcer dyspepsia is different in the different races in Singapore.