The Impact of Alcohol Restriction on Hospital and Emergency Department Service Utilizations in Two Remote Towns in the Kimberley Region of Western Australia.

Background: In a remote region of Western Australia, Kimberley, residents have nearly twice the State average per capita consumption of alcohol, four and a half times the level of alcohol-related hospitalizations and nearly three times the level of alcohol-related deaths. This study aimed to evaluate the long term effects of alcohol sale restrictions on health service utilization in two remote towns in Kimberley. Methods: Sale of high strength packaged alcohol was restricted in Fitzroy Crossing and Halls Creek since October 2007 and May 2009, respectively. Alcohol-related Emergency Department (ED) attendances and hospitalizations utilized by local residents before and after the intervention between 2003 and 2013 was compared by using yearly rates (/1,000 person-years) and interrupted time series analysis with Autoregressive Integrated Moving Average (ARIMA) modeling. The Western Australia specific aetiological fractions (AAFs) were applied to hospital inpatient data for estimation of the proportion of hospital separations attributable to alcohol. Results: In Fitzroy Crossing, there was a significant reduction of over 40% on rates (/1,000 person-years) of alcohol-related acute hospitalizations (54.2 [95% CI: 53.8-54.7] vs. 31.7 [31.4-32.1]) and ED attendances (534.1[532.8-535.5] vs. 294.5 [293.5-295.4]). In Halls Creek, there was a significant reduction of over 50% on rates (/1,000 person-years) of alcohol- related acute hospitalizations (17.7 [17.6-17.8] vs. 8.0 [7.9-8.1]) and ED attendance (248.4 [247.9-248.9] vs. 111.1[110.8-111.5]). Domestic violence and injury related hospitalization rates were also reduced by over 20% in both towns. Conclusions: The total restriction of selling high strength alcohol through a community driven process has shown to be effective in reducing alcohol-related health service utilization in post-intervention period. Continue monitoring is required to address new emerging issues. Future research on health service utilization related to alcohol by using interrupted time series analysis incorporating ARIMA modeling and applying AAFs are recommended for evaluating alcohol-related interventions.

Strategic information for hospital service planning: a linked data study to inform an urban Aboriginal Health Liaison Officer program in Western Australia.

OBJECTIVES: The aim of the present study was to provide descriptive planning data for a hospital-based Aboriginal Health Liaison Officer (AHLO) program, specifically quantifying episodes of care and outcomes within 28 days after discharge. METHODS: A follow-up study of Aboriginal in-patient hospital episodes was undertaken using person-based linked administrative data from four South Metropolitan hospitals in Perth, Western Australia (2006-11). Outcomes included 28-day deaths, emergency department (ED) presentations and in-patient re-admissions. RESULTS: There were 8041 eligible index admissions among 5113 individuals, with episode volumes increasing by 31% over the study period. Among patients 25 years and older, the highest ranking comorbidities included injury (47%), drug and alcohol disorders (41%), heart disease (40%), infection (40%), mental illness (31%) and diabetes (31%). Most events (96%) ended in a regular discharge. Within 28 days, 24% of events resulted in ED presentations and 20% resulted in hospital readmissions. Emergency readmissions (13%) were twice as likely as booked re-admissions (7%). Stratified analyses showed poorer outcomes for older people, and for emergency and tertiary hospital admissions. CONCLUSIONS: Future planning must address the greater service volumes anticipated. The high prevalence of comorbidities requires intensive case management to address case complexity. These data will inform the refinement of the AHLO program to improve in-patient experiences and outcomes.

Burden of stroke in indigenous Western Australians: a study using data linkage.

BACKGROUND AND PURPOSE: Despite the disproportionate burden of cardiovascular disease among indigenous Australians, information on stroke is sparse. This article documents the incidence and burden of stroke (in disability-adjusted life years) in indigenous and non-indigenous people in Western Australia (1997-2002), a state resident to 15% of indigenous Australians comprising 3.4% of the population of Western Australia. METHODS: Indigenous and non-indigenous stroke incidence and excess mortality rates were estimated from linked hospital and mortality data, with adjustment for nonadmitted events. Nonfatal burden was calculated from nonfatal incidence, duration (modeled from incidence, excess mortality, and remission), and disability weights. Stroke death counts formed the basis of fatal burden. Nonfatal and fatal burden were summed to obtain disability-adjusted life years, by indigenous status. RESULTS: The total burden was 55 099 and 2134 disability-adjusted life years in non-indigenous and indigenous Western Australians, respectively. The indigenous to non-indigenous age-standardized stroke incidence rate ratio (≥15 years) was 2.6 in males (95% CI, 2.3-3.0) and 3.0 (95% CI, 2.6-3.5) in females, with similar rate ratios of disability-adjusted life years. The burden profile differed substantially between populations, with rate ratios being highest at younger ages. CONCLUSIONS: The differential between indigenous and non-indigenous stroke burden is considerable, highlighting the need for comprehensive intersectoral interventions to reduce indigenous stroke incidence and improve outcomes. Programs to reduce risk factors and increase access to culturally appropriate stroke services are required. The results here provide the quantitative basis for policy development and monitoring of stroke outcomes.

Disability burden due to stroke in Western Australia: new insights from linked data sources.

BACKGROUND: The disability-adjusted life year index is used extensively to compare disease burden among diseases and locations, but difficulties remain in accurately estimating the nonfatal stroke burden in years lived with disability. AIMS: To improve stroke-related years lived with disability estimates in Western Australia for 2000, by improving the accuracy of component inputs: nonfatal (28-day survivor) incidence, disease duration and disability (severity) weights. METHODS: Nonfatal stroke incidence and the mortality difference between prevalent cases and the general population were estimated from linked hospital and mortality data using the Western Australian Data Linkage System. dismod software used these inputs to model disease duration. Disability weights were estimated from population-based stroke survey data, using indirect health valuation methods and adjusting for prestroke disability. Years lived with disability were calculated from the three components. RESULTS: The annual age-standardised nonfatal incidence (n=1985) was higher in males (121/100,000) than females (96/100,000). The duration varied between 35.8 (females 15-24 years) and 3.4 years (males 85+ years). The mean pre-stroke-adjusted disability weight was higher at 4-months (0.38) than at 12-months (0.31). The age-standardised rate of nonfatal burden in males (302/100,000; 95% CI 290-314) was significantly higher than that in females (250/100,000; 95% CI 240-260). The nonfatal proportion of stroke burden (males 45%; females 37%) was higher than estimated in previous studies. CONCLUSION: This study illustrates that previous reports most likely underestimated disability burden as a contributor to the total stroke burden in Australia. Methodological refinements will contribute to burden of disease studies elsewhere.

Excess mortality rates for estimating the non-fatal burden of stroke in Western Australia: a data linkage study.

BACKGROUND: Non-fatal stroke burden measured in Years Lived with Disability (YLD) requires valid estimates of stroke case fatality to allow modelling of disease duration. In the model, case fatality can be calculated from the absolute risk of mortality in cases in excess of that in the non-diseased. AIMS: Our purpose was to estimate excess mortality rates in 28-day survivors of stroke in Western Australia and to evaluate differentials in survival by stroke type, age and time since the first stroke event. METHOD: Excess mortality among prevalent (first-ever plus existing) survivors was estimated from linked hospital and mortality data. Changes in excess mortality over time were calculated over a 6-year period. RESULTS: Excess mortality increased with age for both males (21 per 1,000 in the 15- to 54-year to 109 per 1,000 in the > or =85-year age group) and females (16 and 122 per 1,000 for the 15- to 54-year and > or =85-year groups, respectively). Survival by stroke sub-types differed at ages <55 years but not >55 years. During the first year excess mortality was markedly higher, after which it was relatively constant for each age group. The assumption of constant rather than changing excess mortality in 28-day survivors of stroke had minimal effect on estimates of duration. CONCLUSION: Measures of excess mortality in prevalent survivors have not previously been available for estimating YLD for stroke. An analysis of all stroke types combined is not likely to substantially bias estimates of non-fatal stroke burden nor is an assumption of constant excess mortality for survivors.

What is the impact of missing Indigenous status on mortality estimates? An assessment using record linkage in Western Australia.

BACKGROUND: The analysis aimed to assess the Indigenous status of an increasing number of deaths not coded with a useable Indigenous status from 1997 to 2002 and its impact on reported recent gains in Indigenous mortality. METHODS: The Indigenous status of WA death records with a missing Indigenous status was determined based upon data linkage to three other data sources (Hospital Morbidity Database System, Mental Health Information System and Midwives Notification System). RESULTS: Overall, the majority of un-coded cases were assigned an Indigenous status, with 5.9% identified as Indigenous from the M1 series and 7.5% from the M2 series. The significant increase in Indigenous male LE of 5.4 years from 1997 to 2002 decreased to 4.0 and 3.6 years using the M1 and M2 series, respectively, but remained significant. For Indigenous females, the non-significant increase in LE of 1.8 years from 1997 to 2002 decreased to 1.0 and 0.6 years. Furthermore, annual all-cause mortality rates were higher than in the original data for both genders, but the significant decline for males remained. CONCLUSION: Through data linkage, the increasing proportion of deaths not coded with a useable Indigenous status was shown to impact on Indigenous mortality statistics in Western Australia leading to an overestimate of improvements in life expectancy. Greater attention needs to be given to better identification and recording of Indigenous identifiers if real improvements in health status are to be demonstrated. A system that captures an individual's Indigenous status once and is reflected in all health and administrative data systems needs consideration within Australia.

Ischemic stroke hospital stay and discharge destination.

PURPOSE: Stroke hospitalizations are among the most expensive, with a mean length of stay (LOS) higher than other hospitalizations. This retrospective study assesses factors influencing ischemic stroke LOS taking into consideration the discharge destination of patients. METHODS: Linked hospital separation records between July 1995 and December 1999 were extracted to determine the first admission for ischemic stroke in Western Australia. Multiple hospitalization records for the same patient were screened to obtain the total duration of hospitalization. Demographic characteristics, hospital type, and medical history of patients were also retrieved. In the presence of censoring and without prior assumption on the time-to-discharge distribution, the Cox's proportional hazards model was used to assess the factors affecting LOS. RESULTS: During the study period, 6469 patients with a first-ever admission for ischemic stroke were identified, with average LOS being 28 days (95% CI, 26-30 days). Hospital stays were significantly longer for females and patients directly admitted to hospitals maintaining a specialist stroke unit, whereas patients residing in rural areas had shorter stays. CONCLUSIONS: The impact of stroke severity and placement in nursing homes after discharge need to be understood to manage LOS and the cost of acute care. Accurate diagnosis upon initial presentation would benefit both the efficiency of hospitals and the outcomes of rural ischemic stroke patients.

Risk factors for ischaemic stroke recurrence after hospitalisation.

OBJECTIVE: To determine risk factors for ischaemic stroke recurrence among patients admitted to hospital for a first-ever occurrence of ischaemic stroke. DESIGN, SETTING AND PATIENTS: Retrospective study involving linked hospitalisation and death records. The cohort comprised 7816 people who were hospitalised for first-ever ischaemic stroke between July 1995 and December 1999 in Western Australia. Cox's proportional hazards model was used to identify risk factors for stroke recurrence. MAIN OUTCOME MEASURES: Time to first recurrence; cumulative recurrence risk; risk factors for recurrence. RESULTS: The median time to first stroke recurrence was 255 days. The cumulative probability of first recurrence was 5.1% (95% CI, 4.6%-5.7%) at 6 months, 8.4% (95% CI, 7.6%-9.1%) at 1 year and 19.8% (95% CI, 18.1%-21.4%) at 4 years. The risk of first recurrence was increased by advancing age (hazard ratio [HR], 1.03; 95% CI, 1.02-1.04), Aboriginality (HR, 1.50; 95% CI, 1.02-2.22), diabetes (HR, 1.27; 95% CI, 1.07-1.51), a history of cardiac conditions (HR, 1.18; 95% CI, 1.01-1.38), post-stroke urinary incontinence (HR, 1.27; 95% CI, 1.03-1.57) and transfer to another hospital on index admission (HR, 1.26; 95% CI, 1.08-1.46). Admission at first stroke occurrence to a hospital maintaining a stroke unit reduced the risk of recurrence (HR, 0.84; 95% CI, 0.72-0.99). CONCLUSION: The risk factors identified in our study have implications for planning secondary prevention strategies. In particular, Aboriginality and transfer to another hospital upon admission for first-ever ischaemic stroke were important risk factors. Research into the level of compliance and access to stroke treatment by Aboriginal patients to prevent further strokes is required.

Factors influencing survival after stroke in Western Australia.

OBJECTIVE: To determine the factors influencing survival among patients admitted to Western Australian hospitals for the first time with stroke or transient ischaemic attack (TIA). DESIGN, SETTING AND PATIENTS: Linked hospitalisation and death records of 7784 patients admitted to hospital for first-ever stroke or TIA between July 1995 and December 1998 were retrieved retrospectively to determine survival; effects of risk factors on death due to stroke were assessed using the Cox proportional hazards regression model. MAIN OUTCOME MEASURES: All-cause stroke survival; short- and long-term stroke survival probabilities. RESULTS: Survival at 28 days was lowest for haemorrhagic stroke. However, following the first month after admission survival after haemorrhagic stroke was similar to, if not higher than, after ischaemic stroke. Among all patients, significant predictors of death were age (all subtypes of stroke), atrial fibrillation (intracerebral haemorrhage and ischaemic stroke), other cardiac conditions (ischaemic stroke and TIA), and sex and diabetes (TIA). Further predictors of death were residence in rural or remote areas (ischaemic stroke), and Aboriginality (TIA). Among 28-day survivors of ischaemic stroke, additional predictors of death were sex, diabetes and urinary incontinence still present 7 days after admission. CONCLUSION: Use of linked hospitalisation and death data allowed us to increase the scope and size of our study compared with previous studies of survival after stroke and TIA in WA. We confirmed the importance of type of stroke, age and comorbidities to this survival, and found that Aboriginality and place of residence are also important.

Truncated negative binomial mixed regression modelling of ischaemic stroke hospitalizations.

A zero-truncated negative binomial mixed regression model is presented to analyse overdispersed positive count data. The study is motivated by the determination of pertinent risk factors associated with ischaemic stroke hospitalizations. Random effects are incorporated in the linear predictor to adjust for inter-hospital variations and the dependency of clustered observations using the generalized linear mixed model approach. The method assists hospital administrators and clinicians to estimate the number of subsequent readmissions based on characteristics of the patient at the index stroke. The findings have important implications on resource usage, rehabilitation planning and management of acute stroke care.