Associations between cardiovascular disease and its risk factors with hearing loss-A cross-sectional analysis.

OBJECTIVES: To investigate the relationship between hearing loss and cardiovascular disease risk factors. DESIGN: Cross-sectional study. METHODS: Participants were recruited between May 2010 and December 2015 and answered a health and risk factor questionnaire. Physical and biochemical assessments were performed. SETTING: A community-based population. PARTICIPANTS: A total of 5107 participants born within the years 1946-1964 enrolled in the Busselton Healthy Ageing Study. MAIN OUTCOME MEASURES: Hearing was assessed behaviourally through the best ear pure-tone average (500, 1000, 2000, 4000 Hz), low-frequency average (250, 500, 1000 Hz) and high-frequency average (4000, 8000 Hz). Self-reported hearing loss, tinnitus and hyperacusis were assessed via questionnaire. Cardiovascular risk factors were assessed via a patient-completed questionnaire and objective measurements including blood pressure, body mass index, waist circumference, lipid profile and glycated haemoglobin. RESULTS: Of the participants, 54% were female, with the mean age of 58 years (range 45-69 years). Age, sex and family history of hearing loss were consistently strong determinants of hearing loss outcomes. After adjusting for these, obesity, current smoking, peripheral arterial disease and history of cardiovascular disease were significantly associated with pure-tone, low-frequency and high-frequency hearing loss. In addition, high blood pressure, triglyceride and glycated haemoglobin were significantly associated with low-frequency hearing loss. There was a graded association between hearing loss and Framingham Risk Score for cardiovascular risk (P<0.001). CONCLUSIONS: Established cardiovascular disease and individual and combined cardiovascular disease risk factors were found to be associated with hearing loss. Future research should prospectively investigate whether targeting cardiovascular disease can prevent hearing loss.

Evaluation of long-term clinical and health service outcomes following coronary artery revascularisation in Western Australia (WACARP): a population-based cohort study protocol.

INTRODUCTION: Coronary artery bypass grafting (CABG) and percutaneous coronary interventions (PCI) are procedures commonly performed on patients with significant obstructive coronary artery disease to relieve symptoms of ischaemia, improve survival or both. Although the efficacy of both procedures at the individual level has been established, the impact of advances in coronary artery revascularisation procedures (CARP) on long-term outcomes and cost-effectiveness at the population level are yet to be assessed. Our aim is to evaluate a minimum of 6-year outcomes and costs for the total population of patients who had CARP in Western Australia (WA) in 2000-2005. METHODS AND ANALYSIS: This retrospective population cohort study will link clinical and administrative health data for a previously defined cohort including all patients in WA who had a CARP in the period 2000-2005. The cohort consists of 19,014 patients who had 21,175 procedures (15,429 PCI and 5746 CABG). We are now collecting a minimum of 6 years follow-up of morbidity and mortality data for the cohort using the WA Data Linkage System, clinical registries and hospital records, with 12 years follow-up for cases in the year 2000. Comparison of long-term outcomes for different CARP will be reported (PCI vs CABG; bare metal stents vs drug-eluting stents vs CABG). Cost-effectiveness analysis of CARP from the perspective of the healthcare sector will be performed using individual level cost data and average costs from Australian Refined Diagnosis Related Groups. ETHICS AND DISSEMINATION: This study has received ethics approval from the University of Western Australia, the Western Australian Department of Health and all participating hospitals. Being a large population cohort study, approval included a waiver of informed consent. All findings will be presented at local, national and international healthcare/academic conferences and published in peer-reviewed journals.

Evidence-based prescribing of drugs for secondary prevention of acute coronary syndrome in Aboriginal and non-Aboriginal patients admitted to Western Australian hospitals.

AIMS: To assess the level of evidence-based drug prescribing for acute coronary syndrome (ACS) at discharge from Western Australian (WA) hospitals and determine predictors of such prescribing in Aboriginal and non-Aboriginal patients. METHODS: All Aboriginal (2002-2004) and a random sample of non-Aboriginal (2003) hospital admissions with a principal diagnosis of ACS were extracted from the WA Hospital Morbidity Data Collection of WA Data Linkage System. Clinical information, history of co-morbidities and drugs were collected from medical notes by trained data collectors. Evidence-based prescribing (EBP) was defined as prescribing of aspirin, statin and beta-blocker or angiotensin-converting enzyme inhibitor/angiotensin II antagonist. RESULTS: Records for 1717 ACS patients discharged alive from hospitals were reviewed. The majority of patients (71%) had EBP, and there was no significant difference between Aboriginal and non-Aboriginal patients (70% vs 71%, P = 0.36). Conversely, a significantly higher proportion of Aboriginal patients had none of the drugs prescribed compared with non-Aboriginal patients (11% vs 7%, P < 0.01). EBP for ACS was independently associated with male sex (odds ratio (OR) 1.63, 95% confidence interval (CI) 1.26-2.11), previous admission for ACS (OR 1.83, 95% CI 1.39-2.42) and diabetes (OR 1.36, 95% CI 1.04-1.79). However, ACS patients living in regional and remote areas, attending district or private hospitals, or with a history of chronic obstructive pulmonary disease were significantly less likely to have ACS drugs prescribed at discharge. CONCLUSIONS: Opportunity exists to improve prescribing of recommended drugs for ACS patients at discharge from WA hospitals in both Aboriginal and non-Aboriginal patients. Attention regarding pharmaceutical management post-ACS is particularly required for patients from rural and remote areas, and those attending district and private hospitals.

Gastro-oesophageal reflux and respiratory symptoms in Busselton adults: the effects of bodyweight and sleep apnoea.

BACKGROUND/AIM: Respiratory symptoms and gastro-oesophageal reflux disease (GORD) are common within the general population. Although a number of epidemiological studies have addressed their relationship, none has investigated the confounding effects of body mass index (BMI) and obstructive sleep apnoea (OSA), both of which are associated with reflux. METHODS: Men and women (2700) from the 2005-2007 cross-sectional Busselton health survey were included. Questionnaire data included demography, information on general health, asthma, cough, wheeze, dyspnoea and reflux symptoms (never, monthly or less often and weekly or more often). BMI, risk of OSA (Berlin questionnaire definition), spirometry and airway hyperresponsiveness (AHR) were recorded. The effects of BMI and OSA on the relationship between respiratory and reflux symptoms were examined using logistic regression models, expressed as adjusted odds ratios for risk of respiratory symptoms by reflux symptom category. RESULTS: Fifty per cent had reflux symptoms (5-10% weekly or more often). Reflux symptoms had strong positive, dose-related associations with cough/phlegm, breathlessness, chest tightness and wheeze in the last 12 months (P < 0.001), but were not related to diagnosed asthma or AHR. Twenty-three per cent were at high risk of OSA and 63% had a BMI of >25 (22% > 30). Increased weight or high risk of OSA did not affect the relationship between respiratory symptoms and reflux symptoms. CONCLUSION: The relationship between reflux and respiratory symptoms was independent of BMI, high risk of OSA or AHR. These findings suggest that reflux contributes directly to respiratory symptoms.

Meat consumption and cooking practices and the risk of colorectal cancer.

BACKGROUND/OBJECTIVES: The association between meat consumption and the risk of colorectal cancer (CRC) has been controversial. One of the difficulties in determining this association has been measurement of different attributes of meat consumption, including cooking methods and level of doneness. SUBJECTS/METHODS: We investigated the association between meat consumption and cooking practices and the risk of CRC in a population-based case-control study in the Western Australian Bowel Health Study. From July 2005 to February 2007, 567 incident CRC cases and 713 controls, who were frequency matched to cases for age- and sex, completed questionnaires on lifestyle and meat consumption. Estimated odds ratios (ORs) comparing meat consumption quartile groups were obtained from multivariate logistic regression models. RESULTS: The amount of red baked meat consumed had a statistically significant inverse trend of association with CRC (Q4 OR=0.73 95% confidence interval 0.53-1.01). When frequency was multiplied by serving size and by doneness, the association remained protective but was no longer statistically significant. The protective trends for red pan-fried meat were also borderline statistically significant. There were no other statistically significant or meaningful associations with any of the types of meat cooked by any method and the risk of CRC. CONCLUSIONS: Our data do not support the hypothesis that meat consumption is a risk factor for CRC.

Changes in case-mix and outcomes of critically ill patients in an Australian tertiary intensive care unit.

Critical care service is expensive and the demand for such service is increasing in many developed countries. This study aimed to assess the changes in characteristics of critically ill patients and their effect on long-term outcome. This cohort study utilised linked data between the intensive care unit database and state-wide morbidity and mortality databases. Logistic and Cox regression was used to examine hospital survival and five-year survival of 22,298 intensive care unit patients, respectively. There was a significant increase in age, severity of illness and Charlson Comorbidity Index of the patients over a 16-year study period. Although hospital mortality and median length of intensive care unit and hospital stay remained unchanged, one- and five-year survival had significantly improved with time, after adjusting for age, gender; severity of illness, organ failure, comorbidity, 'new' cancer and diagnostic group. Stratified analyses showed that the improvement in five-year survival was particularly strong among patients admitted after cardiac surgery (P = 0.001). In conclusion, although critical care service is increasingly being provided to patients with a higher severity of acute and chronic illnesses, long-term survival outcome has improved with time suggesting that critical care service may still be cost-effectiveness despite the changes in case-mix.

The C282Y polymorphism of the hereditary hemochromatosis gene is associated with increased sex hormone-binding globulin and normal testosterone levels in men.

BACKGROUND: Hereditary hemochromatosis resulting either from homozygosity for the C282Y polymorphism of the HFE gene, or compound heterozygosity for C282Y and H63D, manifests with liver disease and hypogonadism. However, it is unclear whether men who are heterozygotes for C282Y or H63D exhibit subtle abnormalities of sex hormone status. AIMS: To evaluate whether heterozygosity for either of the HFE gene polymorphisms C282Y or H63D is associated with circulating testosterone and SHBG in men. SUBJECTS AND METHODS: We performed a cross-sectional analysis of 388 community-dwelling men. Men were genotyped for C282Y and H63D. Sera were analysed for testosterone and SHBG, and insulin resistance was estimated using a homeostatic model (HOMA2-IR). RESULTS: Mean age of men in the cohort was 56.9 yr. Men who were heterozygous for the C282Y polymorphism in the HFE gene had higher SHBG levels than men who did not carry this polymorphism (mean ± SE, 38.2 ± 1.64 vs 32.8 ± 0.71 nmol/l, p=0.006). Total and free testosterone levels did not differ in the two groups. In multivariate analysis adjusting for potential confounders including age, waist circumference, testosterone, and HOMA2-IR, C282Y heterozygosity remained associated with SHBG levels (p<0.001). CONCLUSION: The C282Y polymorphism is associated with SHBG levels in men who do not manifest iron overload. Further studies are needed to clarify potential mechanisms and determine the clinical relevance of this finding.

Changes in the prevalence of asthma in adults since 1966: the Busselton health study.

Asthma prevalence has increased worldwide; although less so in developed countries recently. This study assessed changes in the prevalence of asthma and related symptoms in the Busselton community since 1966. Cross-sectional respiratory health surveys of Busselton adults were conducted in 1966, 1969, 1972, 1975, 1981, 1990 and 2005-2007. Logistic regression models were used to estimate prevalence rates of asthma, respiratory symptoms, smoking, airway hyperresponsiveness (AHR) and atopy and to make comparisons in 2005-2007 and previous survey years. Asthma was defined as ever having doctor-diagnosed asthma (DDA). The prevalence of DDA was around 6% from 1966 to 1975, 8% in 1981 and rose to 19% in 2005-2007. From 1981 to 2005-2007, smoking prevalence declined and obesity and atopy increased but changes in these variables explained only a small part of the increase in DDA. Wheeze and cough/phlegm increased but AHR, breathlessness and doctor-diagnosed bronchitis remained relatively stable over the same period. These observations indicate that the increase in DDA is partly explained by increased symptoms and atopy. The lack of changes in AHR and doctor-diagnosed bronchitis suggests that factors such as diagnostic transfer and increased awareness of asthma have also contributed to the rise in prevalence of DDA.

Effect of an episode of critical illness on subsequent hospitalisation: a linked data study.

Healthcare utilisation can affect quality of life and is important in assessing the cost-effectiveness of medical interventions. A clinical database was linked to two Australian state administrative databases to assess the difference in incidence of healthcare utilisation of 19,921 patients who survived their first episode of critical illness. The number of hospital admissions and days of hospitalisation per patient-year was respectively 150% and 220% greater after than before an episode of critical illness (assessed over the same time period). This was the case regardless of age or type of surgery (i.e. cardiac vs non-cardiac). After adjusting for the ageing effect of the cohort as a whole, there was still an unexplained two to four-fold increase in hospital admissions per patient-year after an episode of critical illness. We conclude that an episode of critical illness is a robust predictor of subsequent healthcare utilisation.

An Australian cardiovascular risk equation for type 2 diabetes: the Fremantle Diabetes Study.

BACKGROUND: There is no valid cardiovascular disease (CVD) risk prediction equation for Australians with diabetes. The aim of this study is to develop and validate a multivariate risk function for 5-year cardiovascular risk prediction in Australian type 2 diabetes patients. METHODS: The Fremantle Diabetes Study is a community-based longitudinal observational study. A total of 1240 type 2 diabetic patients (95.8% of the baseline cohort) with all required risk factor data were followed from baseline (1993-1996) for 5 years or until they experienced a cardiovascular event or died, whichever came first. CVD during follow up was defined as hospitalization for/with myocardial infarction or stroke, and death from cardiac or cerebrovascular causes or sudden death. Validation of the algorithm was performed on an independent diabetic cohort from the Busselton Health Study. RESULTS: During 5570 patient-years of follow up, 185 (14.9%) had at least one CVD event and 175 (14.1%) died (57.7% from CVD). Variables in the final model comprised age, sex, prior CVD, ln(urinary albumin : creatinine ratio), lnHbA(1c), ln(high density lipoprotein-cholesterol), Southern European ethnic background and Aboriginality. The mean 5-year predicted risk of a CVD event was 15.5%. Applied to the Busselton cohort, discrimination of the model was good (AUC = 0.84, P < 0.001) as was the goodness-of-fit (Hosmer-Lemeshow C-test, P= 0.85) and accuracy (mean squared error (95% confidence interval) = 0.09 (0-0.76)). The positive and negative predictive values for a 10% 5-year CVD risk cut-off were 23.4% and 97.7% respectively. CONCLUSION: This simple diabetes-specific 5-year CVD risk equation is the first validated, population-based Australian model. It should have a role in diabetes management in primary and specialist care.

Serum testosterone levels correlate with haemoglobin in middle-aged and older men.

BACKGROUND: Lower testosterone levels are associated with anaemia in older men and women. The relation between testosterone and haemoglobin (Hb) in younger and middle-aged men is less well defined. The aim of the study was to examine the association between testosterone and Hb levels in men spanning middle to older ages. METHODS: A cross-sectional analysis of 492 men aged 30.7-94.5 years from the Busselton Health Survey, Western Australia, was carried out. Haemoglobin (Hb), early-morning serum total testosterone and sex hormone-binding globulin (SHBG) were measured. Free testosterone was calculated using mass action equations. RESULTS: Haemoglobin correlated to total and free testosterone concentrations (r= 0.13, P= 0.003 and r= 0.20, P < 0.001, respectively). Hb and SHBG were inversely correlated (r=-0.14, P= 0.001). Hb increased across lowest to highest quartiles of total testosterone (P= 0.02) and free testosterone (P < 0.001), but not SHBG. After adjusting for age, waist circumference, smoking status, alcohol consumption, renal function and ferritin, total testosterone was associated with Hb (beta= 0.037, P= 0.003) as was free testosterone (beta= 2.32, P < 0.001), whereas SHBG was not associated. CONCLUSION: Testosterone concentration modulates Hb levels in community-dwelling men across a wide age range. Further studies are needed to clarify implications of this association between testosterone and Hb in men.

Impact of new biomarkers of myocardial damage on trends in myocardial infarction hospital admission rates from population-based administrative data.

Use of troponin testing in the diagnosis of myocardial infarction substantially increases the number of cases diagnosed as myocardial infarction among suspected cases in comparison with previous criteria. However, the impact of troponin testing on rates reported in national statistics that use routinely collected hospital morbidity data is uncertain. The authors developed Poisson regression models to estimate the effect of troponin testing on long-term trends in hospital admission rates in Perth, Western Australia, from 1980 to 2004. Troponin tests were used for 10.5% of patients with suspected myocardial infarction in 1996, rising rapidly to more than 90% of patients from 2001 onward. Fitted models that assumed a continuing linear decline estimated that 100% use of troponin testing in cases of suspected myocardial infarction would lead to an apparent increase in hospital admission rates of 42% (95% confidence interval (CI): 28, 56) in men and 21% (95% CI: 4, 41) in women as compared with rates that would be expected if previous linear trends had continued. Smaller effects of 30% (95% CI: 14, 48) in men and -2% (95% CI: -21, 20) in women were found in fitted models that assumed an underlying attenuating trend in the rates. Similarly constructed logistic regression trend models found no significant effect of troponin testing on trends in 28-day case-fatality.

Surgeon experience and trends in intraoperative complications in laparoscopic cholecystectomy.

BACKGROUND: Intraoperative complications, particularly bile duct injuries (BDIs), have increased since the introduction of laparoscopic cholecystectomy (LC). This excess risk is expected to decline as surgeon experience in laparoscopic surgery increases. METHODS: This was a population-based study of trends in intraoperative injuries in 33 309 cholecystectomies carried out in Western Australia between 1988 and 1998, based on hospital discharge abstracts. Endpoints were identified from diagnostic and procedure codes in index or postoperative readmissions, or a register of endoscopic retrograde cholangiopancreatography procedures, and validated using hospital records. Multivariate analysis was used to estimate the risk of complications associated with potential risk factors. RESULTS: Following the introduction of LC in 1991, the prevalence of all complications doubled by 1994 then stabilized, whereas that of BDI declined after 1994. The risk of complications increased with age, was higher in men, teaching and country hospitals, and was higher for LC and more complicated operations. It was lower when intraoperative cholangiography was performed and with increasing surgeon experience. Approximately 20 per cent of all complications and 30 per cent of BDIs were attributable to surgeons who had performed 200 or fewer cholecystectomies in the previous 5 years. CONCLUSION: The risk of intraoperative complications declined with increasing surgical experience and use of intraoperative cholangiography.

The obesity-driven rising costs of type 2 diabetes in Australia: projections from the Fremantle Diabetes Study.

BACKGROUND: The cost of diabetes is high for both the individual and society. Future health-care planning requires patient-level diabetes-attributable health-care cost data that have not previously been available for Australia. AIM: To determine Australian national direct diabetes-attributable health-care costs for known type 2 diabetes in 2000 and project these to 2051. METHODS: A total of 1294 patients with type 2 diabetes was recruited to the Fremantle Diabetes Study between 1993 and 1996. A bottom-up, prevalence-based approach using diabetes-attributable costs provided average annual per patient health-care costs (in year 2000 A$). Costs were extrapolated to 2051 using Australian type 2 diabetes prevalence figures and Australian Bureau of Statistics population projections, assuming that prevalence rates (i) remain at current levels and (ii) rise steadily. RESULTS: Total annual direct diabetes-attributable health-care costs in 2000 in Australia for people > or =25 years with known type 2 diabetes were estimated at A$636 million. As a result of ageing, the number of people with type 2 diabetes will double between 2000 and 2051 with a 2.5-fold increase in diabetes-attributable health-care costs. If obesity and inactivity prevalence rates continue to rise, prevalence rates of type 2 diabetes will further increase. The number of people with type 2 diabetes in 2051 may be 3.5 times higher than in 2000 with a 3.7-fold cost increase. CONCLUSIONS: The financial burden of treating type 2 diabetes could quadruple by 2051 unless more is done to prevent type 2 diabetes and its complications. A smaller proportion of the population will have the capacity to fund these rising health-care costs.

Trends in coronary artery revascularisation procedures in Western Australia, 1980-2001.

OBJECTIVES: To describe trends in the use of coronary artery revascularisation procedures (CARPs) and to determine whether or when CARP rates will stabilise. SETTING: State of Western Australia. PATIENTS: All patients treated by coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) between 1980 and 2001. DESIGN: Descriptive study. MAIN OUTCOME MEASURES: Age standardised rates of first and total CARPs, CABGs, and PCIs. RESULTS: Overall rates for both total and first CARPs among men and women rose steeply from 1980 to 1993, when they abruptly stabilised or actually started to decline. Rates in age groups under 65 years tended to rise earlier in the period and remained relatively flat, while rates for people over the age of 75 years started to rise later and were still increasing at the end of the study. CONCLUSIONS: Despite continuing increases in capacity to perform both CABG and PCI in Western Australia and evidence of continuing increases in the use of CARPs in the elderly population, rates appear to have stabilised for the first time since they were introduced.

Trends in two year risk of repeat revascularisation or death from cardiovascular disease after coronary artery bypass grafting or percutaneous coronary intervention in Western Australia, 1980-2001.

AIMS: To investigate whether, over the 21 year period 1980-2001, there had been a reduction in the risk of repeat revascularisation or death from cardiovascular disease in the cohort of all patients who were treated by coronary revascularisation in Western Australia. SETTING: State of Western Australia. PATIENTS: All patients treated by coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) between 1980 and 2001. DESIGN: Cohort study. MAIN OUTCOME MEASURES: Risk of repeat coronary artery revascularisation procedures (CARP) and risk of death from cardiovascular disease after first CARP. RESULTS: After a CABG procedure, the two year risk of repeat revascularisation remained low (less than 2%) across the period 1980-2001. For PCI, however, this risk declined significantly from 33.6% in 1985-9 to 12.4% in 2000-1. The risk of death from cardiovascular disease after a CARP declined by about 50% between 1985 and 2001. CONCLUSIONS: Outcomes such as the risk of repeat revascularisation and the risk of death from cardiovascular disease have improved significantly for patients who underwent CARPs across the period 1980-2001. This has occurred despite an increasing trend in first CARP rates among older people and those with a recent history of myocardial infarction.

Risk of death in prisoners after release from jail.

OBJECTIVE: To compare the risk of death in a cohort of Western Australian released prisoners with the risk experienced by the general population of Western Australia. METHODS: A cohort study of prisoners in Western Australia whose last date of release ranged from 1 January 1994 to 1 January 1999. Overall mortality and cause of death were determined by data linkage to the Registrar General's record of deaths. RESULTS: Aboriginal prisoners had a significantly lower survival rate after release than non-Aboriginal prisoners (p < 0.0001). When compared with their peers in the Western Australian community, both Aboriginal and non-Aboriginal prisoners were found to have an increased relative risk of death. Female non-Aboriginal released prisoners aged between 20 and 40 years were 17.8 (95% CI 8.1-27.5) times more likely to die than other female non-Aboriginals in Western Australia in the same age range. Male non-Aboriginal prisoners aged 20-40 years were 6.3 (95% CI 5.2-7.4) times more likely to die than their counterparts in the WA community. Female Aboriginal released prisoners were 3.4 (95% CI 1.2-5.6) times more likely to die than their peers, while male Aboriginal released prisoners were 2.9 (95% CI 2.2-3.5) times more likely to die. In their first six months after release, female non-Aboriginal prisoners aged 20 to 40 years were 69.1 (95% CI 17.9-120.3) times more likely to die than their counterparts in the WA community. The main causes of excess death were related to drug and alcohol abuse. CONCLUSION: All prisoners were at greater than expected relative risk of death after release from prison, with female non-Aboriginal prisoners at particularly high relative risk.

Serum ferritin and cardiovascular disease: a 17-year follow-up study in Busselton, Western Australia.

The association between serum ferritin level and coronary heart disease (CHD) and stroke events was evaluated in a long-term Western Australia prospective study in 1981-1998. The cohort consisted of the 1612 men and women aged 40-89 years who participated in the 1981 Busselton Health Survey and who were free of cardiovascular disease at that time. Serum ferritin levels were obtained from serum samples stored frozen since 1981. The outcomes of interest were time to first CHD event (hospital admission or death) and time to first stroke event. Case-cohort sampling was used to reduce costs and preserve serum but still allow efficient analysis. Ferritin assays were performed for 217 CHD cases, 118 stroke cases, and a random sample of 450 of the total cohort. Proportional hazards regression models were used to obtain age-adjusted and multivariate-adjusted hazard ratios for ferritin level in relation to CHD and stroke. The hazard ratio for the highest tertile group compared with the lowest group was 0.96 (95% confidence interval: 0.60, 1.53) for CHD and 1.43 (95% confidence interval: 0.78, 2.64) for stroke. Little or no evidence was found that ferritin level was a risk factor for cardiovascular disease.

Health status of users of hormone replacement therapy by hysterectomy status in Western Australia.

STUDY OBJECTIVES: To compare the demographic, behavioural, and biological correlates of use of hormone replacement therapy (HRT) in women with an intact uterus and women who have undergone hysterectomy. DESIGN: Cross sectional analysis of data from the Busselton Health Study and the 1994 Healthway-National Heart Foundation Risk Factor Survey. SETTING: Busselton and Perth, Western Australia, 1994. PARTICIPANTS: 2540 women aged 35-79 years. MAIN OUTCOME MEASURES: Demographic, behavioural, and biological correlates of use of HRT by hysterectomy status. RESULTS: In women with an intact uterus, after adjustment for age and place of residence, current use of HRT was significantly associated with having a professional level of occupation, ever use of alcohol, having a history of smoking, and a lower body mass index. Current users of HRT had significantly lower levels of total cholesterol and higher levels of triglycerides than non-users. In women who had undergone hysterectomy, the only non-biological characteristic associated with use of HRT was having a history of smoking. Current users of HRT had lower levels of systolic blood pressure, lower levels of LDL cholesterol, higher levels of HDL cholesterol, and higher levels of triglycerides. The association between use of HRT and participation in exercise, level of systolic blood pressure, level of HDL cholesterol, and total/HDL cholesterol ratio varied significantly by hysterectomy status. After adjustment for age and place of residence, the mean levels of systolic and diastolic blood pressure, body mass index, waist/hip ratio, LDL cholesterol, and total/HDL cholesterol ratio were highest in women who had undergone hysterectomy and were not using HRT. CONCLUSIONS: Demographic/behavioural and biological correlates of use of HRT varied depending on hysterectomy status. Demographic and behavioural characteristics were more important as selection factors for use of HRT in women with an intact uterus than in women who had undergone hysterectomy. Women who had undergone hysterectomy and were not using HRT had a significantly worse profile for CHD than did women with an intact uterus. These results indicate that any bias in estimates of the protective effect of HRT on risk of CHD in observational studies is likely to depend on the prevalence of hysterectomy within the study population. Hysterectomy status needs to be taken into account in any studies that investigate the effect of HRT on risk of CHD.

Trends in road injury hospitalisation rates for Aboriginal and non-Aboriginal people in Western Australia, 1971-97.

OBJECTIVE: To examine trends in road injury hospitalisation rates for Aboriginal and non-Aboriginal people in Western Australia. METHODS: Data from the Western Australian Hospital Morbidity Data System for the years between 1971 and 1997 were analysed. Poisson regression models were fitted to determine whether the trends were significant. RESULTS: The rate of hospitalisation due to road injury for Aboriginal people (719.1 per 100 000 population per year) over the time period examined was almost twice as high as that for non-Aboriginal people (363.4 per 100 000 population per year). Overall, the results showed that while hospitalisations from road injury involving non-Aboriginal people have been decreasing by 6.7% per three year period since 1971, the rates of hospitalisation for Aboriginal people have been increasing by 2.6% per three year period. Both of these trends were statistically significant. The alarming increasing trend observed for Aboriginal people was more pronounced in males, those aged 0-14 years and over 45 years, and for those living in rural areas. CONCLUSIONS: As the rates of road injury for Aboriginal people are higher than for non-Aboriginal people, and are also following an increasing trend, road safety issues involving Aboriginal people need to be addressed urgently by health and transport authorities.