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A J Dobson

Publications and source records attributed to A J Dobson.

At least 19 recordsLinked to original sources
PubMed2006

From partying to parenthood: young women's perceptions of cigarette smoking across life transitions.

This study explored influences on adoption, maintenance and cessation of smoking among young women as they experienced life transitions: leaving home, gaining employment or attending college/university, marriage and parenthood. Standardized, open-ended telephone interviews were conducted with 80 women (including never smokers, continuing smokers, recent adopters and quitters) aged 24-29 years, recruited from participants in the Australian Longitudinal Study on Women's Health. The social context of smoking (socializing with other smokers, drinking alcohol and going to pubs and clubs) was perceived to be a predominant influence on smoking from the time young women left home until they settled into a committed relationship or started their own family. Stress was identified as an important factor as they experienced lifestyle changes. An increased sensitivity to the negative aspects of smoking after turning 21 was reported, and around the mid-20s the women became concerned about the addictive nature of cigarettes. Motherhood was seen to carry increased responsibilities to protect children from passive smoking and there was a perceived importance of positive role modelling to protect children from becoming smokers themselves. This study highlights the need for public health campaigns to address the social role that smoking plays in young women's lives, and the perceived use of cigarettes for stress relief. Life changes such as settling down with a partner and the contemplation of motherhood provide opportunities for targeted interventions to promote quitting.

Adolescent↗
PubMed2004

Estimating trends and seasonality in coronary heart disease.

We present two methods of estimating the trend, seasonality and noise in time series of coronary heart disease events. In contrast to previous work we use a non-linear trend, allow multiple seasonal components, and carefully examine the residuals from the fitted model. We show the importance of estimating these three aspects of the observed data to aid insight of the underlying process, although our major focus is on the seasonal components. For one method we allow the seasonal effects to vary over time and show how this helps the understanding of the association between coronary heart disease and varying temperature patterns.

Adult↗
PubMed2004

Current smoking and the risk of non-fatal myocardial infarction in the WHO MONICA Project populations.

BACKGROUND: Cohort studies have shown that smoking has a substantial influence on coronary heart disease mortality in young people. Population based data on non-fatal events have been sparse, however. OBJECTIVE: To study the impact of smoking on the risk of non-fatal acute myocardial infarction (MI) in young middle age people. METHODS: From 1985 to 1994 all non-fatal MI events in the age group 35-64 were registered in men and women in the WHO MONICA (multinational monitoring of trends and determinants in cardiovascular disease) project populations (18,762 events in men and 4047 in women from 32 populations from 21 countries). In the same populations and age groups 65,741 men and 66,717 women participated in the surveys of risk factors (overall response rate 72%). The relative risk of non-fatal MI for current smokers was compared with non-smokers, by sex and five year age group. RESULTS: The prevalence of smoking in people aged 35-39 years who experienced non-fatal MI events was 81% in men and 77% in women. It declined with increasing age to 45% in men aged 60-64 years and 36% in women, respectively. In the 35-39 years age group the relative risk of non-fatal MI for smokers was 4.9 (95% confidence interval (CI) 3.9 to 6.1) in men and 5.3 (95% CI 3.2 to 8.7) in women, and the population attributable fractions were 65% and 55%, respectively. CONCLUSIONS: During the study period more than half of the non-fatal MIs occurring in young middle age people can be attributed to smoking.

Adult↗
PubMed2002

Impact numbers in health policy decisions.

OBJECTIVE: To outline the major methodological issues appropriate to the use of the population impact number (PIN) and the disease impact number (DIN) in health policy decision making. DESIGN: Review of literature and calculation of PIN and DIN statistics in different settings. SETTING: Previously proposed extensions to the number needed to treat (NNT): the DIN and the PIN, which give a population perspective to this measure. MAIN RESULTS: The PIN and DIN allow us to compare the population impact of different interventions either within the same disease or in different diseases or conditions. The primary studies used for relative risk estimates should have outcomes, time periods and comparison groups that are congruent and relevant to the local setting. These need to be combined with local data on disease rates and population size. Depending on the particular problem, the target may be disease incidence or prevalence and the effects of interest may be either the incremental impact or the total impact of each intervention. For practical application, it will be important to use sensitivity analyses to determine plausible intervals for the impact numbers. CONCLUSIONS: Attention to various methodological issues will permit the DIN and PIN to be used to assist health policy makers assign a population perspective to measures of risk.

Decision Making↗
PubMed2002

Impact numbers: measures of risk factor impact on the whole population from case-control and cohort studies.

OBJECTIVE: To describe new measures of risk from case-control and cohort studies, which are simple to understand and relate to numbers of the population at risk. DESIGN: Theoretical development of new measures of risk. SETTING: Review of literature and previously described measures. MAIN RESULTS: The new measures are: (1) the population impact number (PIN), the number of those in the whole population among whom one case is attributable to the exposure or risk factor (this is equivalent to the reciprocal of the population attributable risk); (2) the case impact number (CIN) the number of people with the disease or outcome for whom one case will be attributable to the exposure or risk factor (this is equivalent to the reciprocal of the population attributable fraction); (3) the exposure impact number (EIN) the number of people with the exposure among whom one excess case is attributable to the exposure (this is equivalent to the reciprocal of the attributable risk); (4) the exposed cases impact number (ECIN) the number of exposed cases among whom one case is attributable to the exposure (this is equivalent to the reciprocal of the aetiological fraction). The impact number reflects the number of people in each population (the whole population, the cases, all those exposed, and the exposed cases) among whom one case is attributable to the particular risk factor. CONCLUSIONS: These new measures should help communicate the impact on a population, of estimates of risk derived from cohort or case-control studies.

Case-Control Studies↗
PubMed2001

Determinants of general practitioner use among women in Australia.

This study investigates the use of general practitioner services by women in Australia. Although there is a universal health insurance system (Medicare) in Australia, there are variations in access to services and out of pocket costs for services. Survey data from 2350 mid-age (45-50 years) and 2102 older (70-75 years) women participating in the Australian Longitudinal Study on Women's Health were linked with Medicare data to provide a range of individual and contextual variables hypothesised to explain general practitioner use. Structural equation modelling showed that physical health was the most powerful explanatory factor of general practitioner use. However, after adjusting for self-reported health, out of pocket cost per consultation was inversely associated with use of services. The out of pocket cost was generally lower for women with low socioeconomic status but cost was also directly related to geographical remoteness. Women living in more remote areas had higher out of pocket costs and poorer access to services. Women who reported better access to care were more likely to be satisfied with their most recent general practice consultation and less likely to be sceptical of the value of medical care. These results show the need for health policies that improve the equitable use of general practitioner services in Australia.

Aged↗
PubMed2001

Case fatality after an acute cardiac event: the effect of smoking and alcohol consumption.

The objective of this study was to use a population-based register of acute cardiac events to investigate the association between survival after an acute event and history of smoking and alcohol consumption. The population was all residents of the Lower Hunter Region of Australia aged 25 to 69 years who suffered myocardial infarction or sudden cardiac death between 1986 and 1994. Among 10,170 events, 2504 resulted in death within 28 days. After adjusting for sex, age and medical history, current smokers had a similar risk of dying after an acute cardiac event to never-smokers [odds ratio (OR)=1.10, 95% confidence interval (CI) 0.94-1.29]. People who consumed more than 8 alcoholic drinks per day on more than 2 days per week (OR=1.93, 95% CI 1.39-2.69) and former moderate to heavy drinkers (OR=4.59, 95% CI 3.65-5.76) were more likely to die than people who were nondrinkers. The results of this large community study, suggesting no effect of smoking on case fatality and an increased risk of death after an acute cardiac event for heavy drinkers and former moderate to heavy drinkers, highlight the importance of a population view of case fatality. These results can also shed some light on reasons for the paradoxical results from clinical trials.

Acute Disease↗
PubMed2001

Opportunities for control of coronary heart disease in Australia.

OBJECTIVE: To estimate the number of coronary events that could be prevented in Australia each year by the use of preventive and therapeutic strategies targeted to subgroups of the population based on their levels of risk and need. METHODS: Estimates of risk reduction from the published literature, prevalence estimates of elevated risk factor levels from the 1995 National Health Survey and treatment levels from the Australian collaborating centres in the World Health Organization's MONICA Project were used to calculate numbers of coronary events preventable among men and women aged 35-79 years in Australia. RESULTS: Approximately 14,000 coronary events could be avoided each year if the mean level of cholesterol in the population was reduced by 0.5 mmol/L, smoking prevalence was halved and prevalence of physical inactivity was reduced to 25%. This represents a reduction in coronary events of about 40%. Even with less optimistic targets, a reduction of 20% could be attained, while the achievement of some internationally recommended targets could lead to almost 50% reduction. In the short term, aggressive medical treatment of people with elevated levels of risk factors and established coronary disease offers the greatest opportunity for reducing coronary events. CONCLUSION: A comprehensive approach to reduce levels of behavioural and biological risk factors and improve the use of effective treatment could lead to a large reduction in coronary event rates. In the long term, primary prevention--especially to reduce smoking, lower cholesterol levels and increase exercise--has the potential to reduce the population levels of risk and hence contain the national cost of coronary disease.

Adult↗
PubMed2001

Trends in cigarette smoking in 36 populations from the early 1980s to the mid-1990s: findings from the WHO MONICA Project.

OBJECTIVES: This report analyzes cigarette smoking over 10 years in populations in the World Health Organization (WHO) MONICA Project (to monitor trends and determinants of cardiovascular disease). METHODS: Over 300,000 randomly selected subjects aged 25 to 64 years participated in surveys conducted in geographically defined populations. RESULTS: For men, smoking prevalence decreased by more than 5% in 16 of the 36 study populations, remained static in most others, but increased in Beijing. Where prevalence decreased, this was largely due to higher proportions of never smokers in the younger age groups rather than to smokers quitting. Among women, smoking prevalence increased by more than 5% in 6 populations and decreased by more than 5% in 9 populations. For women, smoking tended to increase in populations with low prevalence and decrease in populations with higher prevalence; for men, the reverse pattern was observed. CONCLUSIONS: These data illustrate the evolution of the smoking epidemic in populations and provide the basis for targeted public health interventions to support the WHO priority for tobacco control.

Adult↗
PubMed2001

Health services research using linked records: who consents and what is the gain?

OBJECTIVE: To assess consent to record linkage, describe the characteristics of consenters and compare self-report versus Medicare records of general practitioner use. METHOD: Almost 40,000 women in the Australian Longitudinal Study on Women's Health were sent a request by mail for permission to link their Medicare records and survey data. RESULTS: 19,700 women consented: 37% of young (18-23 years), 59% of mid-age (45-50 years) and 53% of older women (70-75 years). Consenters tended to have higher levels of education and, among the older cohort, were in better health than non-consenters. Women tended to under-report the number of visits to general practitioners. CONCLUSIONS: Record linkage of survey and Medicare data on a large scale is feasible. The linked data provide information on health and socio-economic status which are valuable for understanding health service utilisation. IMPLICATIONS: Linked records provide a powerful tool for health care research, particularly in longitudinal studies.

Adolescent↗
PubMed2000

Death and readmission in the year after hospital admission with cardiovascular disease: the Hunter Area Heart and Stroke Register.

OBJECTIVES: To compare outcomes one year after hospital admission for patients initially discharged with a diagnosis of acute myocardial infarction (AMI), other ischaemic heart disease (other IHD), congestive heart failure (CHF) or stroke. DESIGN: Cohort study. SETTING: Hunter Area Heart and Stroke Register, which registers all patients admitted with heart disease or stroke to any of the 22 hospitals in the Hunter Area Health Service in New South Wales. PATIENTS: 4981 patients with AMI, other IHD, CHF or stroke admitted to hospital as an emergency between 1 July 1995 and 30 June 1997 and followed for at least one year. MAIN OUTCOME MEASURES: Death from any cause or emergency hospital readmission for cardiovascular disease. RESULTS: In-hospital mortality varied from 1% of those with other IHD to 22% of those with stroke. Almost a third of all patients discharged alive (and 38% of those aged 70 or more) had died or been readmitted within one year. This varied from 22% of those with stroke to 49% of those with CHF. The causes of death and readmission were from a spectrum of cardiovascular disease, regardless of the cause of the original hospital admission. CONCLUSIONS: Data from this population register show the poor outcome, especially with increasing age, among patients admitted to hospital with cardiovascular disease. This should alert us to determine whether optimal secondary prevention strategies are being adopted among such patients.

Aged↗
PubMed2000

Patterns of alcohol consumption in young Australian women: socio-demographic factors, health-related behaviours and physical health.

OBJECTIVE: To determine which socio-demographic factors, health-related behaviours and physical health conditions are associated with non-drinking, binge drinking and hazardous/harmful drinking in young Australian women. METHODS: Cross-sectional data were obtained from the baseline survey of 14,762 young women (aged 18-23 years) enrolled in the Women's Health Australia study in 1996. Associations between a range of drinking patterns and socio-demographic factors, health-related behaviours and health conditions were examined. RESULTS: Half the women were 'low intake' drinkers, a third 'rarely drank' and 9% were non-drinkers; however, 70% reported binge drinking with one-quarter of the binge drinkers doing so at least weekly. Non-drinkers were more likely than drinkers to be married, pregnant, non-smokers, born in non-English speaking countries, to live in the Northern Territory, and to have lower levels of education, employment, and private health insurance. 'Low intake/binge weekly' drinkers (12%) and 'hazardous/harmful' drinkers (5%) were more likely than 'low risk' drinkers to be unmarried; to live in shared accommodation, alone or with their parents; to live in rural or remote areas; to have ever had any sexually transmitted infection; to be current smokers or ex-smokers and to have used unhealthy weight-control practices. CONCLUSIONS: The results confirm findings from other countries about the importance of social conditions as determinants of alcohol consumption by young women. IMPLICATIONS: Health promotion to reduce young women's alcohol consumption needs to be carefully targeted to take account of their demographies, living environments and beliefs.

Adolescent↗
PubMed2000

Trends in coronary heart disease--has the socio-economic differential changed?

OBJECTIVE: To compare both trends in rates of coronary heart disease and levels of coronary risk factors between different socio-economic groups. METHODS: Rates of coronary events for men and women aged 25 to 69 years were estimated from a population-based register in the Lower Hunter Region of New South Wales from 1985 to 1993. Risk factor levels were estimated for men and women aged 35 to 64 years from three surveys of risk factors conducted in 1983, 1988/89 and 1994 in the same study population. RESULTS: There was a decline in major coronary events from 1985 to 1993. The greatest decline was for fatal coronary events, which fell by between 4.3% and 9.1% per year. Trends in event rates were similar for all socio-economic groups, except for trends in non-fatal definite myocardial infarction among women. Women from the areas with high socio-economic status tended to have a greater reduction in non-fatal definite myocardial infarction compared with women from low socio-economic areas. Trends in risk-factor levels were similar except the prevalence of cigarette smoking among women from the lowest quintile of socio-economic status did not decline. CONCLUSION: Prevention strategies seem to have had a beneficial impact on this population, resulting in similar declines in rates of coronary events for all socio-economic groups. However, event rates are still high, suggesting a further reduction in mortality and morbidity is possible. This could be achieved by further reductions in smoking, cholesterol and blood pressure, especially among people from areas with low socio-economic status.

Adult↗
PubMed2000

Access and equity in the provision of general practitioner services for women in Australia.

OBJECTIVE: To assess geographical equity in the availability, accessibility and out-of-pocket costs of general practitioner (GP) services for women in Australia. METHOD: Data on general practice consultations during 1995 and 1996 for women aged 18-23 years (n = 5,260), 45-50 years (n = 7,898) and 70-75 years (n = 6,542) in the Australian Longitudinal Study on Women's Health were obtained from the Health Insurance Commission. A sub-study of 4,577 participants provided data on access to health services. RESULTS: Older women were more likely to have no out-of-pocket costs for their GP consultations, but in all age groups, the proportion was lower in rural areas than in urban areas (older age: 60% rural areas, 76% capital cities; mid-age: 24% rural areas, 40% capital cities; young age: 35% rural areas, 52% capital cities). Among mid-aged women, the median out-of-pocket cost per consultation ranged from $2.11 in capital cities to $6.48 in remote areas. Women living in rural and remote areas gave lower ratings for the availability, accessibility and affordability of health services than women living in urban areas. CONCLUSIONS: This study has shown a striking gradient in financial and nonfinancial barriers to health care associated with area of residence. IMPLICATIONS: The geographical imbalance in the supply and distribution of GP services in Australia has long been recognised but inequities in the affordability of services must also be addressed. Longitudinal survey data and Health Insurance Commission data provide a means to evaluate policies designed to improve access to health services in rural and remote areas.

Adolescent↗
PubMed2000

Cigarette smoking, menstrual symptoms and miscarriage among young women.

OBJECTIVE: To examine associations between cigarette smoking and menstrual symptoms and miscarriage among young women. METHOD: The study sample consists of 14,779 women aged 18-23 years who participated in the mailed baseline survey for the Australian Longitudinal Study on Women's Health, conducted in 1996. The main outcome measures are self reported menstrual symptoms and miscarriages. RESULTS: Current smokers and ex-smokers had an increased risk of menstrual symptoms and miscarriages compared with women who had never smoked, with the highest risk occurring in heavy smokers (adjusted odds ratios for those smoking > or = 20 cigarettes per day: premenstrual tension 1.5 (95% confidence interval 1.3 to 1.7), irregular periods 1.5 (1.3 to 1.8), heavy periods 1.6 (1.4 to 1.9), severe period pain 1.5 (1.4 to 1.7), one or more miscarriages 2.0 (1.5 to 2.8). The odds ratios generally increased with numbers of cigarettes smoked and a younger age of starting to smoke. CONCLUSION: This study suggests that young women who smoke are at higher risk of a range of menstrual problems and miscarriage than those who have never smoked. The immediacy of this risk (in contrast to the longer term risks of chronic disease) can be used to improve the relevance of anti-smoking campaigns targeted to young women.

Abortion, Spontaneous↗
PubMed1999

Hydrogen bonding and C-H...O interactions in bis(4-carboxyquinolinium) sulfate monohydrate.

The title substance, 2C10H8NO2+.SO4(2-).H2O, crystallized in the centrosymmetric space group P1 with two organic cations, one sulfate ion and one water molecule in the asymmetric unit. Seven leading intermolecular hydrogen bonds are formed in this structure: two N-H...O bonds have N...O distances of 2.592 (3) and 2.650 (3) A, while five O-H...O bonds have O...O distances ranging from 2.493 (2) to 3.072 (3) A. All of the potential donors are involved in these bonds, but three of the potential nine acceptors are not. The H and O atoms in all these hydrogen bonds are ordered. The hydrogen bonds form a three-dimensional network. In addition, there are nine significant C-H...O interactions for which the H...O distances are less than the corresponding van der Waals radii sum. The dihedral angle between the best-fit quinoline core plane and the carboxyl group plane is 35.2 (3) degrees for one of the organic cations and 6.4 (4) degrees for the other.

Crystallography, X-Ray↗
PubMed1999

Hydrogen bonding and C-H...X interactions in two triclinic phases of 4-carboxyquinolinium chloride monohydrate.

The title substance, C10H8NO2+.Cl-.H2O, crystallized in the centrosymmetric space group P1 in two phases, alpha and beta, each with one organic cation, one Cl- ion and one water molecule in the asymmetric unit. The principle structural difference in the two asymmetric units lies in the relative orientation of the water molecule. Three hydrogen bonds in the alpha phase have donor-acceptor distances (N...Cl or O...Cl) ranging from 3.052 (1) to 3.189 (2) A, while one has an O...O distance of 2.603 (3) A. Three hydrogen bonds in the beta phase have donor-acceptor distances (N...Cl or O...Cl) ranging from 3.044 (2) to 3.206 (2) A, while two have O...O distances of 2.586 (2) and 3.147 (3) A. The H atoms in all these hydrogen bonds are ordered. Each of these phases has five leading C-H...X interactions, for which the H...X distances are less than, or at most slightly greater than, the corresponding van der Waals radius sums. Taken together, these hydrogen bonds and C-H...X interactions form a three-dimensional network of interactions in each phase. The dihedral angle between the best-fit quinoline core plane and the carboxyl group plane is 25.9 (1) degree for the alpha phase and 20.0 (1) degree for the beta phase.

Crystallography, X-Ray↗