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T Dwyer

Publications and source records attributed to T Dwyer.

At least 109 records · Page 6Linked to original sources
PubMed1992

Thermal environment and sudden infant death syndrome: case-control study.

OBJECTIVE: To compare the thermal environment of infants who died of the sudden infant death syndrome with that of age matched control infants. DESIGN: Case-control study. Infants who died were matched with two controls, one for age and one for age and birth weight. Thermal measurements were conducted at the death scene for cases and at the scene of last sleep for control infants, who were visited unexpectedly within four weeks of the index infant's death on a day of similar climatic conditions. A follow up questionnaire was administered to parents of cases and controls. SETTING: The geographical area served by the professional Tasmanian state ambulance service, which includes 94% of the Tasmanian population. SUBJECTS: 41 infants died of the sudden infant death syndrome at home; thermal observations at death scene were available for 28 (68%), parental questionnaire data were available for 40 (96%). 38 controls matched for age and 41 matched for age and birth weight. RESULTS: Cases had more excess thermal insulation for their given room temperature (2.3 togs) than matched controls (0.6 togs) (p = 0.009). For every excess thermal insulation unit (tog) the relative risk of the sudden infant death syndrome was 1.26 (95% confidence interval 1.05 to 1.52). The average thermal bedding value calculated from parental recall was similar to that observed by attendant ambulance officers (mean difference = 0.4 tog, p = 0.39). Cases were more likely to have been found prone (odds ratio 4.58; 1.48 to 14.11). Prone sleeping position was not a confounder or effect modifier of the relation between excess thermal insulation and the syndrome. CONCLUSIONS: Overheating and the prone sleeping position are independently associated with an increased risk of the sudden infant death syndrome. Further work on infant thermal balance and sudden infant death is required and guidelines for appropriate infant thermal care need to be developed.

Bedding and Linens↗
PubMed1992

Industrial safety engineering--challenges of the future.

Safety management is now entering an era quite different to that which marked its foundation. The multiple challenges facing safety engineering are focused upon. In the United States, France, Britain, and Brazil, safety engineering has experienced fast growth over the past two decades. An increased questioning of the traditional assumptions of the profession in both traditional and postindustrial work has accompanied this growth. New directions of reflection and research are being pursued. Recent research in sociology, where worker perceptions of tasks and their dangers are incorporated into the analysis of accident production, brings promising but still incipient new perspectives to accident research and theory. Simultaneously, novel challenges for safety engineering are posed by the emergence of postindustrial technologies. Some of these threaten large civilian populations, and the knowledge is not currently available to guarantee accident prevention. In this way the responsibilities of safety engineering, both ethical and with regards the provision of information to the public, are brought under the spotlight. The face of safety engineering is being changed.

Accident Prevention↗
PubMed1992

Population-based survey of human sodium and potassium excretion.

1. During the 1989 National Heart Foundation Risk Factor Prevalence Survey a subsample in Hobart collected 24 h urine samples to measure electrolyte excretion. 2. The ranges were 30-344 mmol/24 h for Na+ excretion (mean 160 mmol/24 h for men, 124 mmol/24 h for women), and 25-119 mmol/24 h for K+ excretion (mean 77 mmol/24 h for men, 68 mmol/24 h for women). 3. As in other surveys, women excreted about 20-25% less Na+ and K+ than men, although there was no significant sex difference in the ratio of Na+/K+ excretion. 4. The recommended dietary intake (RDI) for Na+ and K+ was followed simultaneously by 19% of subjects, and 13% had a 24 h urinary Na+/K+ ratio less than or equal to 1.0. 5. Observance of the RDI limited the value of iodized salt for goitre prophylaxis. 6. Sodium excretion rates were outside the therapeutic range of thiazide diuretics in 22% of subjects. 7. Diet groups for long-term prospective cohort studies to test the prophylactic value of avoiding salt could apparently be recruited from existing subsamples of the population.

Adult↗
PubMed1992

Characteristics of the infant thermal environment in the control population of a case-control study of SIDS.

This report examines the thermal environment during last sleep of a control population to investigate how the thermal environment of the infant's bedroom varies by season, external temperature and by certain maternal and infant characteristics. Two age-matched control infants were chosen for each case, one of which was also matched on birthweight. The home visits were not pre-arranged and were matched on climatic conditions, time of year and time period of day for the index case. The initial response rate for controls (n = 108) was 86%. Although there was a large amount of variation in the infant thermal environment, thermal insulation correlated with room temperature (r = -0.44, P = 0.0001) and external temperature (r = -0.30, P = 0.002). The thermal environment of the infant, as defined by excess thermal insulation for room temperature, did not vary by indoor or outdoor temperature, but higher average values were observed in teenage mothers (mean difference = 2.7 tog [95% Cl = 0.3, 5.2]), infants who slept in an adult bed (mean difference = 2.6 tog [-0.1, 5.4]) and infants with an illness (mean difference = 0.8 tog [-0.3, 1.9]). There was a tendency for the thermal environment of infants to be higher and more variable during winter, supporting previous hypotheses that paradoxical overheating may occur in some infants during winter. Further work is required to provide a set of recommendations on the optimal thermal conditions for post-neonatal infants.

Bedding and Linens↗
PubMed1992

Sudden infant death syndrome: seasonality and a biphasic model of pathogenesis.

STUDY OBJECTIVE: This paper examines the relationship between season, age, and the sudden infant death syndrome (SIDS). It provides a theoretical model for the pathogenesis of SIDS and uses it as a framework to consider risk factor mechanism. DESIGN: A case series analysis was used to examine season and age in relation to SIDS and seasonal pattern and age at death distribution of perinatal risk factors. SETTING: The source population for the SIDS cases in this study was all live births in the state of Tasmania, Australia, 1975 to 1987 inclusive. SUBJECTS: Cases were all infants born 1975 to 1987 who died of SIDS on whom birth notification information was available (n = 348). The live birth cohort 1980-87 (n = 55,944) was used as the control population for risk factor identification. MEASUREMENTS AND MAIN RESULTS: The median ages of death for spring, summer, autumn, and winter born infants were 115, 103.5, 91 and 78 days. Spring and summer born infants died at a significantly older median age than winter born infants. The month of birth distribution of SIDS cases did not alter significantly from a uniform, nonseasonal distribution (p greater than 0.25) but month of death was seasonally distributed (p less than 0.01). Premature and low birthweight infants died at an older median age (p less than 0.05) than term and non-low-birthweight infants. An excess of male infant deaths and infant deaths to older mothers occurred during winter (p less than 0.05). CONCLUSIONS: The pathogenesis of SIDS can be represented as a biphasic model with three pathways of risk factor operation. In this study, season influenced the age at death of SIDS infants. We propose that risk factors with a strong seasonal distribution are likely to be operating in the postnatal period.

Female↗
PubMed1992

The industrial safety professionals: a comparative analysis from World War I until the 1980s.

The birth of industrial society produced demand for the services of professionals specialized in matters related to industrial safety. Three professions--safety engineering, industrial medicine, and ergonomics--are examined. These professions are observed to either submit to single sets of demands, to integrate contradictory demands, or to experience scission. Until the late 1960s their growth appears to have been relatively peaceful and uncontroversial. From this period onward, controversy breaks out over questions related to industrial safety, and professions and government administrations grow. Increasingly, the traditional approach of safety professionals is called into question, and they adopt new orientations. These changes are mapped through the examination of data drawn principally from the United States, France, Great Britain, and to a lesser extent Brazil. The traditional standards approach competes with cost-benefit analysis and with systemic safety for influence; in addition, an emergent approach that analyzes accident causes in terms of social relations of work is detected. From Bhopal to Chernobyl, new technologies subject civilian populations to risks of catastrophic accidents, and the action of safety professionals comes under the spotlight. The analysis constructed permits new understandings of the past and the future of these professions.

Accidents, Occupational↗
PubMed1991

Prospective cohort study of prone sleeping position and sudden infant death syndrome.

Studies of the link between prone sleeping position and sudden infant death syndrome have been criticised on grounds of recall bias and for not taking into account possible confounding effects. To avoid recall bias and to allow measurement of important biological factors a prospective cohort study of the cause of sudden infant death syndrome (SIDS) is being conducted. The infants included are those at high risk of the syndrome as assessed by a perinatal score. Of the 3110 members of the cohort born between January, 1988, and end of March, 1990, 23 infants later died of SIDS. Sleep position information was available for 15 of these. Matched analysis to control for the confounding effects of infant birthweight and maternal age indicated that prone sleeping position was associated with an increased risk of SIDS (OR 4.47 95% Cl [1.30-15.43]). The findings are strengthened by the results of a concurrent retrospective case-control study of 42 SIDS cases in which the prone position was also associated with an increased risk of SIDS (unadjusted OR 3.45 [1.59-7.49]).

Case-Control Studies↗
PubMed1991

Iodisation of salt.

Explore the source record for details and available documents.

Cultural Characteristics↗
PubMed1991

Industrial accidents are produced by social relations of work: a sociological theory of industrial accidents.

Industrial accidents are produced by social relations work. This sociological explanation of accidents differs from the hypotheses on which the majority of modern safety practices are based, which reduce accident causes to unsafe acts and unsafe conditions. Accidents are seen as produced at each of three levels of social relations of work (rewards, command and organisation), and also non-socially at the individual-member level. The resulting hypotheses were tested using data collected according to a semi-experimental design in seven plants in which shift (day/night), shift type (rotating/fixed), technological type and management styles were the factors controlled for. Because of the design, machines, materials and, in most cases, workers were the same across shifts and social relations varied. The sociological theory proved capable of explaining most of the variation in inter-shift differences in accident rates, and, when tested statistically, appeared to have greater explanatory power than competing hypotheses. It is concluded that accidents can be prevented by workers who exercise auto-control at all levels and by management which, in the absence of worker orientations favourable to auto-control, engages in safety management as defined sociologically. A practical consequence for ergonomics is that when plant, equipment and processes are to be modified, an attempt to understand their interaction with the social relations of work should be made. A theoretical consequence is that sociological insights should be incorporated into the perspective of the ergonomics discipline.

Journal Article↗
PubMed1991

Assessing school health education programs.

This review focuses on the component of health education directed at achieving changes in health behavior. Much of the work in this field has centered on health behavior that has a role in preventing future disease. Because the evidence is strongest in relation to coronary heart disease (17), considerable effort has been devoted to this area. Walter et al. (34) indicated that the most relevant forms of health behavior to be considered in school-based programs on heart disease are those relating to diet, physical activity, and smoking. Programs relating to each of these behaviors are addressed here.

Adolescent↗
PubMed1991

Prone sleeping position and SIDS: evidence from recent case-control and cohort studies in Tasmania.

The most recent data from the cohort and case-control studies of SIDS and prone position recently reported from Tasmania are reviewed. The cohort analysis was based on 4103 infants born between 1 January 1988 and 1 December 1990 assessed as being at high risk at birth, of whom 29 later died of SIDS. A matched analysis which controlled for infant birthweight and maternal age indicated that prone sleeping position was associated with an increased risk of SIDS (OR 3.92, 95% Cl [1.37-11.24]). The case-control study was based on all (n = 55) Tasmanian SIDS death from October 1989 to April 1991 and matched live controls. The unadjusted odds ratio for prone position and SIDS was 5.04 (95% Cl [2.29-11.11]). The population attributable risk percentage, based on the high risk cohort data, was 0.38 (95% Cl [0.35-0.41]), suggesting that a significant reduction in SIDS incidence might occur if the prevalence of the prone sleeping position in the infant population were reduced. Other factors which may be important for the development of any public health interventions to reduce SIDS based on these findings are discussed.

Case-Control Studies↗
PubMed1990

Differences in modifiable cardiovascular disease risk factors in Australian schoolchildren: the results of a nationwide survey.

Two thousand four hundred schoolchildren ages 9, 12, and 15 years were randomly selected to participate in the Health and Fitness Survey of Australian Schoolchildren in 1985. Data on blood lipids, aerobic fitness, blood pressure, and obesity were obtained through physical measurement. Information on socioeconomic status and ethnic origin was collected via questionnaire. Serum total cholesterol and low and high-density lipoprotein cholesterol were lowest in the oldest age group. Girls had significantly higher serum lipid levels, the difference being greatest at 15 years. However, comparison of the total cholesterol/high-density lipoprotein cholesterol ratio showed a trend in the direction of decreasing risk with increasing age for girls, with the reverse being found in boys. Fifteen-year-old girls were also the fattest and least fit of all the children, but had significantly lower systolic and diastolic blood pressures than their male peers. Children of Asian ethnic origin had significantly lower systolic and diastolic blood pressures and a significantly higher mean high-density lipoprotein cholesterol and were less likely to be overweight compared with other ethnic groups. Children from Mediterranean/Middle-East countries were significantly fatter and had a higher mean diastolic blood pressure than the other ethnic groups. These differences were detectable at age 9 years. Children from lower socioeconomic backgrounds were fatter and had a significantly lower mean high-density lipoprotein cholesterol and higher mean serum triglyceride levels. As with ethnic origin, these differences were detectable at age 9 years. The results demonstrate that age, sex, ethnic origin, and socioeconomic status can be used as variables to describe mean differences in the levels of cardiovascular risk factors in the national population of children. As some elevations in risk factors appear to be present in the youngest age group and these levels correlate with fatty streak and fibrous plaque formation in young adulthood, preventive programs should aim at intervention prior to puberty.

Adolescent↗
PubMed1990

The development of a model for predicting infants at high risk of sudden infant death syndrome in Tasmania.

A statutory 'Notification of Birth' form, containing obstetric and perinatal information, has been routinely collected for Tasmanian deliveries since 1974. For the period 1980 to 1984, birth notification data was collected for over 99% of Tasmanian deliveries. This data was examined for the 130 cases of sudden infant death syndrome (SIDS) that occurred from 1980 to 1984 and for 610 controls. It was then used to construct an at-birth scoring system to predict infants at higher risk of SIDS in the postneonatal period. A predictive model of the relative risk of SIDS was developed by fitting a binomial/logistic generalised linear model to the binary 1980-1984 case control data with birth variables used as predictors. The final predictive model contained five variables (maternal age, infant sex, birth weight, month of birth and feeding practice) and had a sensitivity of 62% and specificity of 73%. The model was then tested on independent birth cohorts from 1985 and 1986 and found to have a sensitivity of 47% and specificity of 77%. The risk of SIDS in the group of infants classified as high risk was 7.9 per 1000 live births and in the group at low risk it was 2.5 per 1000 live births. In addition, the model predicted 74% of neonatal deaths occurring during these 2 years. This compares well with other predictive models developed elsewhere. The predictive model will be used to identify infants at high risk for SIDS in a prospective cohort study.

Cohort Studies↗
PubMed1989

Cigarette smoking in Australian schoolchildren.

Six thousand, four hundred and fifty-one schoolchildren who were aged nine to 15 years completed a questionnaire about their patterns of cigarette use, as part of the nation-wide Health and Fitness Survey of Australian Schoolchildren which was conducted in 1985. The survey yielded figures for the prevalence of cigarette smoking by age, sex, socioeconomic status and ethnic origin. It also provided data on the relationship between parental smoking and smoking in children. By the age of 15 years, 32.4% of the girls and 26.0% of the boys in the study sample had smoked at least one cigarette in the seven days before they were surveyed. In some of the age-groups, the average number of cigarettes that were consumed by girl smokers equalled or exceeded that of their male counterparts. There were no significant differences in the prevalence of current cigarette smoking with differences in socioeconomic status. This finding contrasts with the pattern of use in adults. Ethnic origin was a statistically-significant predictor of smoking behaviour in children. Significantly-fewer children of Asian ethnic origin were current smokers. Parental smoking status also appeared to be an important determinant of smoking behaviour in schoolchildren. This influence was more important for girls than for boys, particularly when the mother was a smoker. The over-all findings suggest that many features of the adult pattern of cigarette use are established by the age of 15 years. The findings also supported the trend towards increased cigarette consumption by girls compared with boys that was noted by earlier researchers. These findings should encourage a serious reappraisal of the role of cigarette advertising in the promotion of smoking in young persons.

Adolescent↗
PubMed1989

Fall in coronary heart disease mortality in U.S.A. and Australia due to sudden death: evidence for the role of polyunsaturated fat.

Epidemiological studies have been reviewed which provide suggestive evidence of an association between the fall in coronary heart disease mortality in the U.S.A and Australia since 1967, characterized by a fall in sudden deaths, to the increase in polyunsaturate fat consumption that has occurred in both countries since 1960. This association led directly in the same institution to carefully designed experimental studies undertaken in the rat, and a non-human primate, the marmoset (Callithrix jacchus jacchus) with a heart and lipid metabolism more closely resembling that of man. In both animal species, a vegetable fat diet had a protective effect against the increase in contractility of isolated papillary muscles induced by age, the addition of animal fat, or by isoprenaline in vitro. Similar effects were observed following coronary artery ligation, where the extent of dysrhythmia was greatly reduced by supplementing the diet with a linoleic acid rich vegetable oil. It is concluded that the combination of epidemiological and experimental evidence indicates a protective effect of dietary polyunsaturates against sudden cardiac death. This work illustrates the value of the integration of epidemiological and experimental approaches to the aetiology of disease.

Animals↗