Search PubMed⌕ Search

Biomedical subjects

T H Lam

Publications and source records attributed to T H Lam.

At least 91 records · Page 5Linked to original sources

The relationship between fibrinogen and other coronary heart disease risk factors in a Chinese population.

Few studies have examined fibrinogen in Chinese populations in which the incidence of coronary heart disease (CHD) is lower than that in the West. This study aimed to examine the relationship between fibrinogen and other CHD risk factors in Hong Kong Chinese. Fibrinogen was measured by the Clauss method in 1359 men and 1405 women aged 25-74 years, randomly selected from the Hong Kong population. Mean fibrinogen level increased with age, from 2.22 g/l in those aged 25-34 years to 2.76 g/l in 65-74 years in men, and from 2.42 to 2.94 g/l respectively in women. The most important factors associated with fibrinogen were age, obesity and blood lipid levels in both genders. In men, smoking was associated with higher fibrinogen levels and cessation of smoking with lower levels. Prospective studies are needed to examine the role of fibrinogen in CHD in Chinese and other Asian populations.

Adult↗

The correlates of depressed mood in adolescents in Hong Kong.

PURPOSE: Most studies of depressed mood and its correlates in adolescents have been conducted in Western countries. This study examined the relationship between a broad range of stressors and depressed mood in a community sample of Hong Kong adolescents. METHODS: Secondary school students (n = 996) completed the Chinese Beck Depression Inventory (C-BDI), provided demographic information, and indicated their perceptions of family and peer relationships, school function and pressures, and subjective health, and some measures salient to the Hong Kong environment: triad gang pressure, religiosity, and intent to emigrate. The correlation between C-BDI and these variables was assessed in bivariate and multivariate analyses. RESULTS: Hong Kong adolescents reported higher levels of depressive symptoms than a comparison group of Western teenagers. Girls showed more symptoms than boys. All stressors correlated in bivariate analyses with C-BDI, indicating similar influences on depressed mood in Western and Hong Kong teenagers. In multivariate analyses, the stressors contributed cumulatively to the C-BDI score. Perceptions of a lack of parental understanding and peer acceptance appeared as the strongest variables in predicting depressed mood. CONCLUSIONS: Depressed mood is highly prevalent among Hong Kong teenagers. Stressors play a cumulative role in their relationship to mood. Our findings point to the importance of broad screening of this vulnerable population.

Adolescent↗

Influence of educational level and marital status on dietary intake, obesity and other cardiovascular risk factors in a Hong Kong Chinese population.

OBJECTIVES: To examine the influence of education and marital status on dietary intake, body mass index, waist hip ratio, blood pressure, fasting and 2 h glucose, and lipid profile in adult Hong Kong Chinese. DESIGN: Randomized age and sex stratified survey. SUBJECTS: One thousand and ten subjects aged 25-74 y (500 men, 510 women) recruited for the 1995-96 Hong Kong Dietary and Cardiovascular Risk Prevalence Survey. MEASUREMENTS: Dietary intake was estimated using a food frequency method. Information on education level and marital status was included in the questionnaire. Anthropometry and biochemical parameters were measured using standard methods. RESULTS: After adjustment for age, higher levels of education are associated with higher percentage protein intake in men, higher percentage fat intake in women, higher nutrient density of fibre and calcium in both men and women, and higher nutrient density of protein, fat, niacin, vitamin D, and polyunsaturated fatty acid in women. Consumption of fruits was also higher in women, and that of dairy products higher in men. Body mass index and waist-hip ratio were lower with increasing levels of education in women, while lower mean systolic BP was observed in men. Single women had lower nutrient densities of vitamin D and iron, and lower consumption of vegetables and fish, compared with married women. Body mass index was lower in both single men and women. Single men had a better cardiovascular risk factor profile, in that diastolic BP, triglycerides and cholesterol/HDL ratio were lower, in addition to a lower body mass index. CONCLUSION: Higher education level is associated with a healthier diet and lower prevalence of overweight.

Adult↗

A prospective analysis of stress and academic performance in the first two years of medical school.

AIM: This study provides prospective, longitudinal data on the relationship between stress-related measures and academic performance during the first two years of medical school. METHODS: First year medical students (n = 121) were surveyed prior to beginning classes (wave 1), and again 8 months later (wave 2). Personality variables predisposing to distress (optimism and trait anxiety), stress response (depression and state anxiety), and stress management strategies were assessed at wave 1 and wave 2. Pre-medical academic scores, and grades at the end of five assessment periods over the course of the first 2 years of medical school were also obtained. RESULTS AND CONCLUSIONS: As expected, pre-medical-school academic performance strongly predicted performance in medical school. Academic performance before and during medical school was negatively related to reported stress levels. On bivariate correlations, there were numerous significant relationships between stress reported at waves 1 and 2, and medical school academic performance assessed after these measures. In addition there were modest negative correlations between self-reported coping strategies of 'humour' and 'wishful thinking', and consequent academic performance. However, the predictive value of stress and its management on prospective academic performance was much decreased once pre-medical-school performance was statistically controlled.

Adolescent↗

Effects of ambient air pollution and environmental tobacco smoke on respiratory health of non-smoking women in Hong Kong.

BACKGROUND: Two-thirds of complaints received by the Hong Kong Environmental Protection Department in 1988 were related to poor air quality. In July 1990 legislation was implemented to reduce fuel sulphur levels. The intervention led to a reduction in respiratory symptoms and bronchial hyperresponsiveness of primary school children. The objectives of this study were to investigate the differences in respiratory health between non-smoking women living in the more polluted district (Kwai Tsing) and those living in the less polluted district (Southern); to assess the impact of the government air quality intervention; and to study the effect of environmental tobacco smoke on respiratory health in non-smoking women in both districts. METHOD: A total of 3405 non-smoking women, aged 36.5 years (standard deviation = 3.0), from two districts with good and poor air quality respectively before the intervention were followed yearly from 1989 to 1991. Binary latent variable modelling was used to summarize the six respiratory symptoms and to estimate the effects of risk factors. RESULTS: In 1989, living in the polluted district was associated with poor respiratory health (odds ratio [OR] = 1.55, 95% confidence interval [CI]: 1.11-2.17, P < 0.01). After the intervention, in the polluted district only, sulphur dioxide levels fell by up to 80% and sulphate concentrations in respirable particulates by 38%. Between 1989 and 1990-1991, there was no significantly greater decline (P > 0.241) in the more polluted compared with the less polluted district for poor respiratory health. In 1989, the effects on poor respiratory health for exposure to two or more categories of smokers relative to none in the home (OR = 1.80, 95% CI: 1.15-2.83, P < 0.01) were higher but not significantly than those for living in polluted relative to less polluted district (95% CI of the two effects overlapping each other). CONCLUSIONS: Environmental tobacco smoke (ETS) and outdoor air pollution had independent adverse effects on respiratory health of non-smoking women and improvement in air quality had produced some but non-significant benefits.

Adolescent↗

Passive smoking and respiratory symptoms in primary school children in Hong Kong. Child Health and Activity Research Group (CHARG).

1. We aimed to study whether passive smoking is associated with respiratory ill health in primary school children in Hong Kong. 2. In this cross-sectional study, a standardised structured questionnaire was used to obtain information on respiratory symptoms, smokers in the household and smoking habit of the children. A random sample of 30 primary schools was included. Four classes were randomly selected for each school, one class each from each school year of primary 3-6. A total of 3964 children aged 8 - 13 years completed the questionnaire during October 1995-May 1996. The response rate was over 94%. 3. In 3480 children who had never smoked, after adjusting for gender, age, place of birth and living district, the odds ratios (95% confidence interval) were: (a) throat problems, 1.35 (1.08-1.68); (b) cough, 1.54 (1.28-1.84); (c) phlegm, 1.43 (1.21-1.70); (d) wheezing, 1.21 (0.89-1.41); (e) nose problems, 1.17 (1.02-1.35). The odds ratios increased with increasing number of smokers at home (P for trend < 0.001; except for wheezing, P=0.3). The odds ratios for having any of the above symptoms for one, two and three smokers at home were respectively 1.15 (0.99-1.34), 1.48 (1.16-1.88) and 2.03 (1.47 - 2.81); P for trend < 0.001. 4. We conclude that the results provide further evidence that passive smoking is a cause of respiratory ill health in school children in Hong Kong.

Adolescent↗

Passive smoking exposure of sick children in Hong Kong.

1. This study aims to investigate the extent of passive smoking exposure of sick children in Hong Kong; their father's smoking behaviors and their mother's action to protect the child from environmental tobacco smoke (ETS). 2. This cross-sectional survey was the first phase of a randomized controlled trial on a health education intervention provided by nurses in the general paediatric wards of four major hospitals in Hong Kong. The subjects are non-smoking mothers of sick children admitted to hospital and with a smoking husband living together in the same household with the child. Eligible subjects completed a self-administered baseline questionnaire before entering into the trial. 3. All the 848 children whose mothers completed the questionnaire during December 1997 to April 1998 had a smoking father. They constituted about 24% (95% CI: 22.6-24.9%) of all the sick children during the same period. More than half of the children's fathers (55%; 51.6-58.3%) smoked 1-14 cigarettes per day and about 68% (64.7-71.0%) of them were daily smokers for over 10 years. Over half (53%; 49.4-56.2%) of the fathers smoked 1-14 cigarettes at home every day. About 21% of the fathers smoked near the child occasionally and 31% (27.4-33.6%) smoked 1-14 cigarettes near the child per day. About 16% of the children lived with more than one smoker (2-3). About 86% (83.3-88.0%) of the children had 1-3 smokers who smoked at home and 61% (58.1 - 64.7%) of them had 1-3 smokers who smoked near them every day. However, 70% of the children were reported by their mothers as exposed to ETS at home. This percentage (70%) was less than the percentage (86%) of smokers who smoked at home daily. About 31.1% of the mothers reported symptoms of coughing and running nose (20.6%) in their children when they were exposed to ETS. To protect the child from ETS exposure, 43% of the mothers requested the father not to smoke near the child, 33.1% requested the father to smoke less cigarettes and 31.5% advised the father to quit smoking. 4. In conclusion, sick children in Hong Kong are at risk of exposure to ETS, but not all mothers are aware of the health risks and their actions were inadequate. There is a critical need to promote awareness of ETS exposure and the health risks in the family in Hong Kong so as to reduce illness and hospital admission in children.

Adolescent↗

Suicide ideation and its relationship to depressed mood in a community sample of adolescents in Hong Kong.

A sample of 996 Chinese adolescents in Hong Kong provided information about their suicide ideation. Their depressive symptoms were measured by the Chinese Beck Depression Inventory (C-BDI), and a broad range of stressors were also assessed as potential predictors to level of suicide ideation. The stressors and C-BDI scores predicted 33% of the variance in suicide ideation. In boys, most of the prediction was attributable to C-BDI scores, suggesting that depression mediated the effects of stressors. In girls, C-BDI scores, perceptions of low parental caring, and high conflict with parents had additive effects in predicting level of suicide ideation. This study contributes needed information about a non-Western population and highlights gender differences.

Adolescent↗

A review on studies of smoking and coronary heart disease in China and Hong Kong.

PURPOSE: To document and review all the published reports on smoking and coronary heart disease (CHD) in China and Hong Kong, and to estimate the risks of CHD due to smoking. DATA SOURCES: Papers cited in Medline, Chinese Biomedical Literature Disc and Chinese Medical Current Contents, references in review papers, conference papers and abstracts. STUDY SELECTION: All published reports which had findings on smoking and CHD were included. DATA EXTRACTION: Reports on 13 cross-sectional, 16 case-control and 13 prospective studies were included. Available data on risk estimates from 23 studies were extracted and pooled odds ratios (OR) and relative risks (RR) were calculated using Mantel-Haenszel's methods. RESULTS: In China in 1970s, most results, which were from cross-sectional studies, did not show an association between smoking and CHD. In the 1980s, most case control studies found an association but the prospective studies did not. In the 1990s, there was stronger evidence from prospective studies mainly in men. The relative risk was about 1.90 in men and about 2.50-3.50 in women although the 95% confidence interval for the latter was wide. Dose response relationships were observed in 12 studies. In Hong Kong, there were one cross-sectional and two case control studies. CONCLUSIONS: The existing evidence supports that smoking is a cause of CHD in Chinese, particularly in men. More data in women are needed to quantify the risk more precisely. The risk estimates probably indicate only the early stage of a growing tobacco epidemic.

China↗

Tobacco advertisements: one of the strongest risk factors for smoking in Hong Kong students.

STUDY OBJECTIVE: To describe the prevalence of smoking in junior secondary school students in Hong Kong and to analyse the relationship between a range of risk factors and ever-smoking experience, including tobacco advertisements. METHODS: Cross-sectional survey using an anonymous standardised self-administered questionnaire. SETTING: 61 randomly selected secondary schools in Hong Kong. PARTICIPANTS: 6,304 form 1 to 3 Chinese students from 172 classes (51% girls and 49% boys; 90% were aged 12 to 15 years). RESULTS: The smoking status (95% confidence interval) was: (1) never smoker, 71.1% (70.0%-72.2%), (2) tried only, 15.5% (14.6%-16.4%), (3) used to smoke but not now, 4.2% (3.7%-4.7%), (4) smoked < 1 cigarette per week, 2.9% (2.5%-3.4%), (5) smoked 1-6 per week, 1.7% (1.4%-2.0%), and (6) smoked > 6 per week, 4.5% (4.0%-5.0%). In a backward stepwise logistic regression model, ever-smoking (including categories 2 to 6 above) was independently associated with thirteen factors, including gender (boys), increasing age, place of birth (outside Hong Kong, mainly China), poor knowledge of the hazards of smoking, positive attitudes to smoking, smoking in family members, participation in tobacco promotional activities, and perception of cigarette advertisements as attractive. Among the strongest associations observed was the youth's perception of cigarette advertisements as attractive, with the adjusted odds ratio (95% confidence interval) of 2.68 (2.33-3.07). CONCLUSIONS: Smoking among young people is an important public health problem. Although the causes are multifactorial, in Hong Kong environmental tobacco advertising is an important risk factor that can be removed by banning all forms of tobacco promotion to young people.

Adolescent↗

Respiratory symptoms due to active and passive smoking in junior secondary school students in Hong Kong.

BACKGROUND: Evidence on respiratory symptoms due to smoking and passive smoking in children is mainly derived from studies in Western countries. Evidence from the East was required to support stronger tobacco control policy in Asia. This study aimed to analyse the relationship between respiratory symptoms and smoking status in junior secondary students and between respiratory symptoms and family smoking in never-smoking students. METHODS: In a cross-sectional survey in 1994, anonymous questionnaires were administered to a two-stage cluster probability sample of 6304 students, aged mostly 12-15 years, from 172 classes of 61 schools in Hong Kong. RESULTS: Significant linear trends were found between smoking and the prevalence of throat and nose problems, cough and phlegm, and wheezing. The odds ratio (OR), after adjustment for age, gender, area of residence, type of housing and correlation within schools and classes (cluster effects), for smoking at least weekly ranged from 1.35 to 4.84. In never-smoking children, significant trends were found between the number of smokers living with the children and throat and nose problems, cough and phlegm, and recent wheezing. The adjusted OR and 95% confidence interval (CI) for any cough or phlegm symptoms was 1.19 (95% CI: 1.01-1.47) for one smoking household member, 1.38 (95% CI: 1.07-1.79) for two and 1.85 (95% CI: 1.19-2.85) for three (P for trend <0.001). Increased OR were found for father and mother smoking. CONCLUSIONS: This study provides strong evidence that both active and passive smoking can cause respiratory ill health in Chinese children in Hong Kong. Urgent measures are needed to protect children from the health hazards of active and passive smoking in Asia.

Adolescent↗

Economic burden of environmental tobacco smoke on Hong Kong families: scale and impact.

STUDY OBJECTIVE: To examine the financial cost of doctor consultations for cough, phlegm, and wheeze in children living in a home where family members smoke compared with those not exposed to environmental tobacco smoke. To model these costs to provide the Territory of Hong Kong with estimates of potentially avoidable health care resource use. DESIGN: Cross sectional questionnaire survey. SUBJECTS AND SETTING: All children (10,615) in classes primary 3 to 6 (aged 8-13 years) attending 27 schools in two districts of Hong Kong in 1992 and their parents. MEASUREMENTS AND MAIN RESULTS: Doctor consultations during the previous three months for symptoms of either cough, phlegm or wheeze were higher in younger children, ranging from 22.9% in 8 year olds to 8.4% in those aged 12 or over. For those children living in homes with one, or more than one, smoker category (there were four categories of smokers: father, mother, siblings, others), the adjusted odds ratios (95% confidence intervals) for a doctor consultation for any of these symptoms were 1.15 (1.01, 1.31) and 1.38 (1.14, 1.67) respectively. Using US$15 as the minimum cost incurred per consultation, the expected direct cost per annum per child of doctor consultations was 14% higher for children living in a one smoker category home and 25% for two or more compared with exposure to no smokers in the home. Using these values on a territory wide basis, the annual avoidable direct cost associated with exposure to tobacco smoke in children from birth to 12 years of age ranged from US$338,042 to US$991,591. CONCLUSIONS: Exposure to environmental tobacco smoke not only provides a respiratory health risk for children but also an avoidable excess cost to the family's financial resources and health service providers.

Child↗

Dietary intake and practices in the Hong Kong Chinese population.

OBJECTIVES: To examine dietary intake and practices of the adult Hong Kong Chinese population to provide a basis for future public health recommendations with regard to prevention of certain chronic diseases such as cardiovascular disease, hypertension, and osteoporosis. PARTICIPANTS: Age and sex stratified random sample of the Hong Kong Chinese population aged 25 to 74 years (500 men, 510 women). METHOD: A food frequency method over a one week period was used for nutrient quantification, and a separate questionnaire was used for assessment of dietary habits. Information was obtained by interview. RESULTS: Men had higher intakes of energy and higher nutrient density of vitamin D, monounsaturated fatty acids and cholesterol, but lower nutrient density of protein, many vitamins, calcium, iron, copper, and polyunsaturated fatty acids. There was an age related decrease in energy intake and other nutrients except for vitamin C, sodium, potassium, and percentage of total calorie from carbohydrate, which all increased with age. Approximately 50% of the population had a cholesterol intake of < or = 300 mg; 60% had a fat intake < or = 30% of total energy; and 85% had a percentage of energy from saturated fats < or = 10%; criteria considered desirable for cardiovascular health. Seventy eight per cent of the population had sodium intake values in the range shown to be associated with the age related rise in blood pressure with age. Mean calcium intake was lower than the FAO/WHO recommendations. The awareness of the value of wholemeal bread and polyunsaturated fat spreads was lower in this population compared with that in Australia. There was a marked difference in types of cooking oil compared with Singaporeans, the latter using more coconut/palm/mixed vegetable oils. CONCLUSION: Although the current intake pattern for cardiovascular health for fat, saturated fatty acid, and cholesterol fall within the recommended range for over 50% of the population, follow up surveys to monitor the pattern would be needed. Decreasing salt consumption, increasing calcium intake, and increasing the awareness of the health value of fibre may all be beneficial in the context of chronic disease prevention.

Adult↗

Comparison between two districts of the effects of an air pollution intervention on bronchial responsiveness in primary school children in Hong Kong.

STUDY OBJECTIVE: This study examined the impact on children's respiratory health of a government air quality intervention that restricted the sulphur content of fuels to 0.5% from July 1990 onwards. DESIGN/SETTING/PARTICIPANTS: This study examined the changes, one and two years after the introduction of the intervention, in airway hyperreactivity of non-asthmatic and non-wheezing, primary 4, 5, and 6, school children aged 9-12 years living in a polluted district compared with those in a less polluted district. Bronchial hyperreactivity (BHR)(a 20% decrease in FEV1 provoked by a cumulative dose of histamine less than 7.8 mumol) and bronchial reactivity slope (BR slope) (percentage change in logarithmic scale in FEV1 per unit dose of histamine) were used to estimate responses to a histamine challenge. The between districts differences after the intervention were studied to assess the effectiveness of the intervention. MAIN RESULTS: In cohorts, comparing measurements made before the intervention and one year afterwards, both BHR and BR slope declined from 29% to 16% (p = 0.026) and from 48 to 39 (p = 0.075) respectively in the polluted district; and from 21% to 10% (p = 0.001) and 42 to 36 (p > 0.100) in the less polluted district. Comparing measurements made in 1991 (one year after intervention) with those in 1992 (two years after intervention), only the polluted district showed a significant decline from 28% to 12% (p = 0.016) and from 46 to 35 (p = 0.014), for BHR and BR slope respectively, with a greater decline in both responses (p = 0.018 and 0.073) than in the less polluted district. CONCLUSION: Bronchial hyperresponsiveness tests can be used to support the evaluation of an air quality intervention. The demonstrated reduction in bronchial hyperresponsiveness is an indication of the effectiveness of the intervention.

Air Pollutants↗

The public health harm of tobacco and its prevention in Hong Kong.

This paper briefly reviews the health hazards associated with smoking, including passive smoking, with specific reference to local (Hong Kong) evidence. A Medline search of Hong Kong papers from January 1966 to January 1998 was made, and these and other relevant papers were reviewed. In Hong Kong, at least 10 people die daily from smoking- related diseases. Local studies show that smoking is associated with lung cancer, oesophageal cancer, liver cancer, ischaemic heart disease, peripheral vascular disease, ischaemic stroke, peptic ulcer, osteoporosis, impaired lung function, respiratory symptoms, and other adverse health effects. Smoking in pregnant women can result in smaller babies being born. Pooled results from four case-control studies show a 60% excess risk of lung cancer due to exposure to environmental tobacco smoke. Several studies confirm the link between exposure to environmental tobacco smoke and respiratory illness, hospitalisation, and asthma in children. The risks of smoking (one of every two smokers will be killed by tobacco) are not well known and are underestimated by both doctors and the public. Stronger health messages and more local evidence are needed to support tobacco control in Hong Kong.

Journal Article↗