Patterns of Medicare-funded primary health and specialist consultations in Aboriginal and non-Aboriginal Australians in the two years before hospitalisation for ischaemic heart disease.

BACKGROUND: Ischaemic heart disease (IHD) remains the leading cause of morbidity and mortality for both Aboriginal and non-Aboriginal Australians. Patterns of primary and specialist care in patients leading up to the first hospitalisation for IHD potentially impact on prevention and subsequent outcomes. We investigated the differences in general practice (GP), specialist and emergency department (ED) consultations, and associated resource use in Aboriginal and non-Aboriginal people in the two years preceding hospitalisation for IHD. METHODS: Linked-data were used to identify first IHD admissions for Western Australians aged 25-74 years in 2002-2007. Person-linked GP, specialist and ED consultations were obtained from the Medicare Benefits Schedule (MBS) and ED records to assess health care access and costs for the preceding 2 years. RESULTS: Aboriginal people constituted 4.7% of 27,230 IHD patients, 3.5% of 1,348,238 MBS records, and 14% of 33,170 ED presentations. Aboriginal (vs. non-Aboriginal) people were younger (mean 50.2 vs 60.5 years), more commonly women (45.2% vs 28.4%), had more comorbidities [Charlson index≥1, 35.2% vs 26.3%], were more likely to have had GP visits (adjusted rate-ratio 1.07, 95% CI 1.02-1.12), long/prolonged (16.0% vs 11.9%) consults and non-vocationally registered GP consults (17.1% vs 3.2%), but less likely to received specialist consults (mean 1.0 vs 4.1). Mean number of urgent/semi-urgent ED presentations in the year preceding the IHD admission was higher in Aboriginal people (2.9 vs 1.9). Aboriginal people incurred 2.7% of total associated MBS expenditure (estimated at $59.7 million). Mean total cost per person was 43.3% lower in Aboriginal patients, with cost differentials being greatest in diabetic and chronic kidney disease patients. CONCLUSIONS: Despite being over-represented in urgent/semi-urgent ED presentations and admissions for IHD, Aboriginal people were under-resourced compared with the rest of the population, particularly in terms of specialist care prior to first IHD hospitalisation. The findings underscore the need for better primary and specialist shared care delivery models particularly for Aboriginal people.

Impact of population ageing on growing demand for emergency transportation to emergency departments in Western Australia, 2005-2020.

OBJECTIVE: The aim of the present paper is to quantify the impact of population ageing on demand for emergency transportation (ET) to EDs in Western Australia (WA). METHODS: A population-based longitudinal study using the statewide ED presentation data from 2005-2014 was used to predict ET demand in 2020, stratified by age group and sex. RESULTS: From 2005 to 2014, 14.9% of all ED presentations arrived by ET. The number rose from 94 369 (13.9%) in 2005 to 153 374 (15.5%) in 2014, a compound annual growth of 5.5%. Of those presentations, 55.2% resulted in hospital admission. The proportion was higher in older age groups (64.5% in 65-74 years, 67.1% in 75-84 years and 68.4% in ≥85 years). Of ED presentations arriving by ET in age group ≥65 years, 70.9% were Australasian Triage Scale category 1, 2 or 3. The rate of ET per 1000 population increased in all age groups and sex. The highest growth was in the older age groups: from 86.6, 187.0 and 512.1 in ages 65-74 years, 75-84 years and ≥85 years, respectively, in 2005 to 102.5, 226.7 and 613.6 in 2014, and are expected to increase to 115.1, 264.3 and 707.7 by 2020. The ET demands in these age groups were projected to increase annually by 5.0%, 3.6% and 4.9%, respectively, in the next 6 years, comparing to less than 4.5% in the younger age groups. CONCLUSION: There has been a continuous rise in ET demand in WA, particularly in older people who have a higher urgency and requirement for admission.

A comparison of multivariate and univariate time series approaches to modelling and forecasting emergency department demand in Western Australia.

OBJECTIVE: To develop multivariate vector-ARMA (VARMA) forecast models for predicting emergency department (ED) demand in Western Australia (WA) and compare them to the benchmark univariate autoregressive moving average (ARMA) and Winters' models. METHODS: Seven-year monthly WA state-wide public hospital ED presentation data from 2006/07 to 2012/13 were modelled. Graphical and VARMA modelling methods were used for descriptive analysis and model fitting. The VARMA models were compared to the benchmark univariate ARMA and Winters' models to determine their accuracy to predict ED demand. The best models were evaluated by using error correction methods for accuracy. RESULTS: Descriptive analysis of all the dependent variables showed an increasing pattern of ED use with seasonal trends over time. The VARMA models provided a more precise and accurate forecast with smaller confidence intervals and better measures of accuracy in predicting ED demand in WA than the ARMA and Winters' method. CONCLUSION: VARMA models are a reliable forecasting method to predict ED demand for strategic planning and resource allocation. While the ARMA models are a closely competing alternative, they under-estimated future ED demand.

Growth in Western Australian emergency department demand during 2007-2013 is due to people with urgent and complex care needs.

OBJECTIVES: To determine the magnitude and characteristics of the increase in ED demand in Western Australia (WA) from 2007 to 2013. METHODS: We conducted a population-based longitudinal study examining trends in ED demand, stratified by area of residence, age group, sex, Australasian Triage Scale category and discharge disposition. The outcome measures were annual number and rate of ED presentations. We calculated average annual growth, and age-specific and age-standardised rates. We assessed the statistical significance of trends, overall and within each category, using the Mann-Kendall trend test and analysis of variance ANOVA. We also calculated the proportions of growth in ED demand that were attributable to changes in population and utilisation rate. RESULTS: From 2007 to 2013, ED presentations increased by an average 4.6% annually from 739,742 to 945,244. The rate increased 1.4% from 354.1 to 382.6 per 1000 WA population (P = 0.02 for the trend). The main increase occurred in metropolitan WA, age 45+ years, triage category 2 and 3 and admitted cohorts. Approximately three-quarters of this increase was due to population change (growth and ageing) and one-quarter due to increase in utilisation. CONCLUSION: Our study reveals a 4.6% annual increase in ED demand in WA in 2007-2013, mostly because of an increase in people with urgent and complex care needs, and not a shift (demand transfer) from primary care. This indicates that a system-wide integrated approach is required for demand management.

Hospital mental health admissions in women after unsuccessful infertility treatment and in vitro fertilization: an Australian population-based cohort study.

OBJECTIVE: To examine the association between in vitro fertilization (IVF) and later admission to hospital with a mental health diagnosis in women who remained childless after infertility treatment. METHODS: This was a population-based cohort study using linked administrative hospital and registry data. The study population included all women commencing hospital treatment for infertility in Western Australia between the years 1982 and 2002 aged 20-44 years at treatment commencement who did not have a recorded birth by the end of follow-up (15 August 2010) and did not have a hospital mental health admission prior to the first infertility admission (n=6,567). Of these, 2,623 women had IVF and 3,944 did not. We used multivariate Cox regression modeling of mental health admissions and compared women undergoing IVF treatment with women having infertility treatment but not IVF. RESULTS: Over an average of 17 years of follow-up, 411 women in the cohort were admitted to hospital with a mental health diagnosis; 93 who had IVF and 318 who did not. The unadjusted hazard ratio (HR) for a hospital mental health admission comparing women who had IVF with those receiving other infertility treatment was 0.50 (95% confidence interval [CI] 0.40-0.63). After adjustment for age, calendar year and socio-economic status the HR was 0.56 (95% CI 0.44-0.71). CONCLUSIONS: IVF treatment is associated with a reduced risk of hospital mental health admissions in women after unsuccessful infertility treatment. This may be explained by the healthy cohort effect.

Predicting the number of emergency department presentations in Western Australia: a population-based time series analysis.

OBJECTIVE: To predict the number of ED presentations in Western Australia (WA) in the next 5 years, stratified by place of treatment, age, triage and disposition. METHODS: We conducted a population-based time series analysis of 7 year monthly WA statewide ED presentation data from the financial years 2006/07 to 2012/13 using univariate autoregressive integrated moving average (ARIMA) and multivariate vector-ARIMA techniques. RESULTS: ED presentations in WA were predicted to increase from 990,342 in 2012/13 to 1,250,991 (95% CI: 982,265-1,519,718) in 2017/18, an increase of 260,649 (or 26.3%). The majority of this increase would occur in metropolitan WA (84.2%). The compound annual growth rate (CAGR) in metropolitan WA in the next 5 years was predicted to be 6.5% compared with 2.0% in the non-metropolitan area. The greatest growth in metropolitan WA would be in ages 65 and over (CAGR, 6.9%), triage categories 2 and 3 (8.3% and 7.7%, respectively) and admitted (9.8%) cohorts. The only predicted decrease was triage category 5 (-5.3%). CONCLUSIONS: ED demand in WA will exceed population growth. The highest growth will be in patients with complex care needs. An integrated system-wide strategy is urgently required to ensure access, quality and sustainability of the health system.

Long-term use and cost-effectiveness of secondary prevention drugs for heart disease in Western Australian seniors (WAMACH): a study protocol.

INTRODUCTION: Secondary prevention drugs for cardiac disease have been demonstrated by clinical trials to be effective in reducing future cardiovascular and mortality events (WAMACH is the Western Australian Medication Adherence and Costs in Heart disease study). Hence, most countries have adopted health policies and guidelines for the use of these drugs, and included them in government subsidised drug lists to encourage their use. However, suboptimal prescribing and non-adherence to these drugs remains a universal problem. Our study will investigate trends in dispensing patterns of drugs for secondary prevention of cardiovascular events and will also identify factors influencing these patterns. It will also assess the clinical and economic consequences of non-adherence and the cost-effectiveness of using these drugs. METHODS AND ANALYSIS: This population-based cohort study will use longitudinal data on almost 40,000 people aged 65 years or older who were hospitalised in Western Australia between 2003 and 2008 for coronary heart disease, heart failure or atrial fibrillation. Linking of several State and Federal government administrative data sets will provide person-based information on drugs dispensed precardiac and postcardiac event, reasons for hospital admission, emergency department visits, mortality and medical visits. Dispensed drug trends will be described, drug adherence measured and their association with future all-cause/cardiovascular events will be estimated. The cost-effectiveness of these long-term therapies for cardiac disease and the impact of adherence will be evaluated. ETHICS AND DISSEMINATION: Human Research Ethics Committee (HREC) approvals have been obtained from the Department of Health (Western Australian #2011/62 and Federal) and the University of Western Australia (RA/4/1/1130), in addition to HREC approvals from all participating hospitals. Findings will be published in peer-reviewed medical journals and presented at local, national and international conferences. Results will also be disseminated to consumer groups.

Mental illness related disparities in diabetes prevalence, quality of care and outcomes: a population-based longitudinal study.

BACKGROUND: Health care disparity is a public health challenge. We compared the prevalence of diabetes, quality of care and outcomes between mental health clients (MHCs) and non-MHCs. METHODS: This was a population-based longitudinal study of 139,208 MHCs and 294,180 matched non-MHCs in Western Australia (WA) from 1990 to 2006, using linked data of mental health registry, electoral roll registrations, hospital admissions, emergency department attendances, deaths, and Medicare and pharmaceutical benefits claims. Diabetes was identified from hospital diagnoses, prescriptions and diabetes-specific primary care claims (17,045 MHCs, 26,626 non-MHCs). Both univariate and multivariate analyses adjusted for socio-demographic factors and case mix were performed to compare the outcome measures among MHCs, category of mental disorders and non-MHCs. RESULTS: The prevalence of diabetes was significantly higher in MHCs than in non-MHCs (crude age-sex-standardised point-prevalence of diabetes on 30 June 2006 in those aged ≥20 years, 9.3% vs 6.1%, respectively, P < 0.001; adjusted odds ratio (OR) 1.40, 95% CI 1.36 to 1.43). Receipt of recommended pathology tests (HbA1c, microalbuminuria, blood lipids) was suboptimal in both groups, but was lower in MHCs (for all tests combined; adjusted OR 0.81, 95% CI 0.78 to 0.85, at one year; and adjusted rate ratio (RR) 0.86, 95% CI 0.84 to 0.88, during the study period). MHCs also had increased risks of hospitalisation for diabetes complications (adjusted RR 1.20, 95% CI 1.17 to 1.24), diabetes-related mortality (1.43, 1.35 to 1.52) and all-cause mortality (1.47, 1.42 to 1.53). The disparities were most marked for alcohol/drug disorders, schizophrenia, affective disorders, other psychoses and personality disorders. CONCLUSIONS: MHCs warrant special attention for primary and secondary prevention of diabetes, especially at the primary care level.

Influence of Y3+, Bi3+ content on photoluminescence of YVO4:Dy3+ phosphor induced by ultraviolet excitation.

YxVO4: 0.01Dy3+ and Y0.99-x V04: 0.01Dy3+, xBi3+ phosphors were synthesized by chemical coprecipitation method. Their crystal structure, micromorphology and photoluminescence (PL) properties were investigated by X-ray diffraction (XRD), scan electron microscopy (SEM) and spectrofluorometer. YxVO4: 0.01Dy3+ and Y0.99--xVO4: 0.01Dy3+, xBi3+ phosphors have a broad excitation band from about 250 to 350 nm including a strongest peak at about 310 nm. Under its excitation, the emission spectra exhibits two sharp peaks, one of which centered at about 483 nm for 4F9/2-->6H15/2 transition of Dy3+ and the other at about 574 nm due to the 4F9/2-->6 H13/2 transition of Dy+. For YxVO4: 0.01Dy3+, (x = 0.94, 0.97, 0.99, 1.01, 1.03) phosphor, with increasing value of x, the body color of phosphor changes from yellow to white and the strongest peak in the excitation spectra shifts a little to shorter wavelength. It is detrimental to luminous intensity when Y3+ content deviates stoichiometric ratio. For Y0.99--x VO4: 0.01Dy3+, xBi3+ (x = 0.01, 0.05, 0.1, 0.15, 0.2, 0.25) phosphor, the samples have extraneous bismuth vanadium oxide phase except for the major tetragonal zircon structure when x > or = 0.20. With increasing value of x, the band edge in the excitation spectra shifts to longer wavelength, the excitation intensity and luminous intensity increase early and decrease late. When the value of x is 0.01, the intensities increase evidently. In addition, the influence of Y3+ or Bi3+ on the color temperature of emission and micromorphology of YVO4:Dy3+ is slight.

The impact of mental illness on potentially preventable hospitalisations: a population-based cohort study.

BACKGROUND: Emerging evidence indicates an association between mental illness and poor quality of physical health care. To test this, we compared mental health clients (MHCs) with non-MHCs on potentially preventable hospitalisations (PPHs) as an indicator of the quality of primary care received. METHODS: Population-based retrospective cohort study of 139,208 MHCs and 294,180 matched non-MHCs in Western Australia from 1990 to 2006, using linked data from electoral roll registrations, mental health registry (MHR) records, hospital inpatient discharges and deaths. We used the electoral roll data as the sampling frame for both cohorts to enhance internal validity of the study, and the MHR to separate MHCs from non-MHCs. Rates of PPHs (overall and by PPH category and medical condition) were compared between MHCs, category of mental disorders and non-MHCs. Multivariate negative binomial regression analyses adjusted for socio-demographic factors, case mix and the year at the start of follow up due to dynamic nature of study cohorts. RESULTS: PPHs accounted for more than 10% of all hospital admissions in MHCs, with diabetes and its complications, adverse drug events (ADEs), chronic obstructive pulmonary disease (COPD), convulsions and epilepsy, and congestive heart failure being the most common causes. Compared with non-MHCs, MHCs with any mental disorders were more likely to experience a PPH than non-MHCs (overall adjusted rate ratio (ARR) 2.06, 95% confidence interval (CI) 2.03-2.09). ARRs of PPHs were highest for convulsions and epilepsy, nutritional deficiencies, COPD and ADEs. The ARR of a PPH was highest in MHCs with alcohol/drug disorders, affective psychoses, other psychoses and schizophrenia. CONCLUSIONS: MHCs have a significantly higher rate of PPHs than non-MHCs. Improving primary and secondary prevention is warranted in MHCs, especially at the primary care level, despite there may be different thresholds for admission in people with established physical disease that is influenced by whether or not they have comorbid mental illness.

How effective is in vitro fertilization, and how can it be improved?

OBJECTIVE: To measure IVF effectiveness, which is defined as the cumulative incidence of live delivery over real time in women after commencing IVF treatment. DESIGN: Population-based retrospective cohort study. SETTING: IVF clinics in Western Australia (WA). PATIENT(S): All women ages 20-44 years inclusive at start of treatment, commencing IVF in 1982-1992 and 1993-2002 at clinics in WA (n = 8,275). INTERVENTION(S): Data on IVF cycles were extracted from hospital records and a statutory reproductive technology register and linked to records of births. MAIN OUTCOME MEASURE(S): Cumulative incidence of an IVF-attributed live delivery and cumulative incidence of an IVF-attributed or IVF treatment-independent live delivery. RESULT(S): IVF effectiveness in the 1993-2002 cohort was 47% overall. It was highest in women ages 20-29 years at the start of treatment, measuring 58%; and 79% with the inclusion of IVF treatment-independent deliveries, and declined to 22% and 33%, respectively, in women ages 40-44 years. Couples underwent, on average, only three cycles, even though the cumulative probability of a live delivery increased with each successive cycle for at least the first five cycles. CONCLUSION(S): IVF effectiveness could be improved if women, particularly those over 35, underwent more cycles.

Do users of mental health services lack access to general practitioner services?

OBJECTIVE: To compare rates of visits to a general practitioner between users and non-users of mental health services (MHS). DESIGN, PARTICIPANTS AND SETTING: Population-based retrospective cohort study of 204 727 users and 294 076 matched non-users of MHS in Western Australia from 1 January 1990 to 30 June 2006, based on linked records of the use of MHS, hospital admissions, Medicare claims for GP and specialist services, electoral roll registration and deaths. MAIN OUTCOME MEASURES: Adjusted rate ratios (ARRs) for the number of visits to GPs by users of MHS relative to non-users, and for different categories of mental disorders. RESULTS: Relative to non-users of MHS, the ARR of visits to GPs by users of MHS was 1.622 (95% CI, 1.613-1.631) overall, and was elevated in each separate category of mental illness. ARRs were highest for alcohol/drug disorders, schizophrenia and affective psychoses (2.404, 1.834 and 1.798, respectively). The results were not changed by location (metropolitan, rural or remote addresses). However, the 4% of MHS users with no fixed address had a very low ARR of visits to GPs (0.058; 95% CI, 0.057-0.060). CONCLUSIONS: Users of MHS visit GPs substantially more often than non-users, with the exception of those with no fixed address who seldom see a GP at all.

Impact of laparoscopic cholecystectomy on hospital utilization.

OBJECTIVE: The objective of the present study was to assess the impact of laparoscopic cholecystectomy (LC) and associated endoscopic retrograde pancreatography (ERCP) on hospital utilization. BACKGROUND: Laparoscopic cholecystectomy (LC) has resulted in marked reductions in average length of hospital stay; but population-based studies of hospital utilization have generally not taken into account increased cholecystectomy rates or associated increases in pre and postoperative admissions. METHODS: We conducted a population-based study of all residents of Western Australia who underwent cholecystectomy in the period 1980-2000. Record linkage was used to identify pre and postoperative admissions, and to estimate aggregate length of stay per case based on all relevant admissions. We estimated trends in cholecystectomy rates, proportions of cases with related pre and postoperative hospital admissions, average aggregate length of stay per case and total bed utilization per unit of population. RESULTS: The introduction of LC was associated with a sustained increase in rates of cholecystectomy of 25%. Similar increases occurred in the percentage of cases with related preoperative and postoperative admissions. Average length of stay for index admissions declined by nearly 60% compared with 50% for all related admissions. Per capita hospital utilization for index admissions decreased by 45% compared with 38% for index and associated admissions combined, and 32% for all admissions for biliary disease. CONCLUSIONS: Reduced hospital utilization associated with LC was partly offset by increases in pre and postoperative admissions and a sustained increase in cholecystectomy rates. Record linkage is required to assess the true impact of new technologies on hospital utilization.