Kate Brameld

Validation of linked administrative data on end‐stage renal failure: application of record linkage to a ‘clinical base population’

Objective: To evaluate the use of record linkage to monitor the occurrence of end‐stage renal failure in Western Australia in 1980–94.

Socio-demographic disparities in the uptake of prenatal screening and diagnosis in Western Australia.

Introduction:  Since the early 1980s, prenatal screening using ultrasound and biochemical markers has been used to refine the risk of Down syndrome and other fetal anomalies prior to considering fetal karyotyping. The performance of prenatal screening is subject to ongoing monitoring in Western Australia. The collection of these data can also assist in the identification of any potential inequities of access to prenatal screening within the state‐wide programme.

First trimester predictors of adverse pregnancy outcomes.

Aim: To identify first trimester indicators of adverse pregnancy outcomes.

The Impact of Single Gene and Chromosomal Disorders on Hospital Admissions of Children and Adolescents: A Population-Based Study

Background: It is well recognized that genetic disease makes a significant contribution to childhood illness. Here, we present recent population data describing the impact of single gene and chromosomal disorders on hospital admissions of children and adolescents. Methods: Hospital admissions for patients aged 0–19 years between 2000 and 2006, with a single gene or chromosomal disorder, were extracted from the Western Australian Hospital Morbidity Data System using 296 diagnosis codes identified from the International Statistical Classification of Diseases, Tenth Revision, Australian Modification. Data extracted for each patient included the number, length and cost of all admissions. Results: Between 2000 and 2006, 14,197 admissions were identified for 3,271 patients aged 0–19 years with single gene and chromosomal disorders, representing 2.6% of admissions and 4.3% of total hospital costs in this age group. Patients with genetic disorders had more admissions and stayed longer in hospital than patients admitted for any reason. Specific disorders associated with a high demand on hospital services included cystic fibrosis, Down syndrome, osteogenesis imperfecta, thalassemia, and von Willebrand’s disease. Conclusions: Children and adolescents with single gene and chromosomal disorders placed higher demands on hospital services than other patients in their age group, but were responsible for a relatively small proportion of hospital admissions and costs. These data will enable informed planning of health care services for patients with single gene and chromosomal disorders in Western Australia.

Demographic factors as predictors for hospital admission in patients with chronic disease

Objective: To identify demographic predictors of hospital admission for chronic disease.

Increasing 'active prevalence' of cancer in Western Australia and its implications for health services.

Objective:To measure the active and total prevalence of cancer in Western Australia from 1990–98 and to examine trends in utilisation of hospital services by prevalent cancer patients.

Use of a state data bank to measure incidence and prevalence of a chronic disease: End-stage renal failure

The Western Australian Health Services Research Linked Database was used to examine trends in the incidence rate and prevalence of end-stage renal failure and to describe treatment patterns in these patients. Linked hospital morbidity and mortality records from 1980 to 1994 were selected if a record had a principal diagnosis or procedure of chronic renal failure, dialysis, or renal transplantation. Patient records were grouped according to the stage of care (predialysis, dialysis, transplant, or death). A total of 1, 046 patients with a principal diagnosis or procedure that met our criteria for end-stage renal failure was admitted to the hospital from 1985 to 1994. Trends in the incidence rate and prevalence of end-stage renal failure by sex and race, patterns of care, indices of comorbidity, and waiting time to transplantation were calculated. Results showed that both the incidence rate and prevalence of end-stage renal failure increased from 1986 to 1994, most noticeably in the aboriginal population. Rates of renal failure in 1994 were 15 times greater in aborigines than in nonaborigines. Of the hospital patients, 73.5% received dialysis three times a week. Complications associated with dialysis treatment were the most common cause of comorbid hospitalization. The mean waiting time to transplantation was 503 days for those who had a transplant and 6.3 years for all patients. The escalating numbers of patients undergoing renal dialysis, the high cost of maintaining them on dialysis, and the additional use of hospital services for comorbid conditions highlight the need to develop programs to prevent the occurrence of renal failure, particularly in the aboriginal population.

The collective impact of rare diseases in Western Australia: an estimate using a population-based cohort

Purpose:It has been argued that rare diseases should be recognized as a public health priority. However, there is a shortage of epidemiological data describing the true burden of rare diseases. This study investigated hospital service use to provide a better understanding of the collective health and economic impacts of rare diseases.Methods:Novel methodology was developed using a carefully constructed set of diagnostic codes, a selection of rare disease cohorts from hospital administrative data, and advanced data-linkage technologies. Outcomes included health-service use and hospital admission costs.Results:In 2010, cohort members who were alive represented approximately 2.0% of the Western Australian population. The cohort accounted for 4.6% of people discharged from hospital and 9.9% of hospital discharges, and it had a greater average length of stay than the general population. The total cost of hospital discharges for the cohort represented 10.5% of 2010 state inpatient hospital costs.Conclusions:This population-based cohort study provides strong new evidence of a marked disparity between the proportion of the population with rare diseases and their combined health-system costs. The methodology will inform future rare-disease studies, and the evidence will guide government strategies for managing the service needs of people living with rare diseases.Genet Med advance online publication 22 September 2016

The use of end-quintile comparisons to identify under-servicing of the poor and over-servicing of the rich: A longitudinal study describing the effect of socioeconomic status on healthcare

BackgroundTo demonstrate the use of end-quintile comparisons in assessing the effect of socio-economic status on hospital utilisation and outcomes in Western Australia.MethodsHospital morbidity records were extracted from the WA Data Linkage System for the period 1994–99, with follow-up to the end of 2000. Multivariate modelling was used to estimate the effect of socio-economic status on hospital admission rates, average and total length of stay (LOS), cumulative incidence of readmission at 30 days and one year, and case fatality at one year.ResultsThe study demonstrated higher rate ratios of hospital admission in the more disadvantaged quintiles: rate ratios were 1.31 (95% CI 1.25–1.37) and 1.32 (1.26–1.38) in the first quintile (most disadvantaged) and the second quintile respectively, compared with the fifth quintile (most advantaged). There was a longer total LOS in the most disadvantaged quintile compared with quintile 5 (LOS ratio 1.24; 1.23–1.26). The risk of readmission at 30 days and one year and the risk of death at one year were also greater in those with greater disadvantage: the hazard ratios for quintiles 1:quintile 5 were 1.07 (1.05–1.09), 1.17 (1.16–1.18) and 1.10 (1.07–1.13) respectively. In contradiction to the trends towards higher hospital utilisation and poorer outcomes with increasing social disadvantage, in some MDCs the rate ratio of quintile 1:quintile 2 was less than 1, and quintile 4:quintile 5 was greater than 1. For all surgical admissions the most disadvantaged had a significantly lower admission rate than the second quintile.ConclusionThis study has shown that the disadvantaged within Western Australia are more intensive users of hospital services but their outcomes following hospitalisation are worse, consistent with their health status. Instances of overuse in the least disadvantaged and under use in the most disadvantaged have also been identified.

Possession of health insurance in Australia – how does it affect hospital use and outcomes?

Objective: To assess the effect of possession of private health insurance on hospital use and outcomes in Western Australia. Method: Hospital morbidity records were extracted from the Western Australian (WA) Data Linkage System for all 22 major diagnostic categories (MDCs) for the period 1994–99, with follow-up to the end of 2000. Multivariate modelling techniques were used to estimate the effect of possession of private health insurance on hospital admission rates, average and total length of stay (LOS), cumulative incidence of admission at 30 days and one year, and case fatality at one year. Results: Possession of private health insurance had significant effects on hospital use and outcomes, even after adjustments for age, sex, aboriginality, socioeconomic status, location and comorbidity. Non-insured patients tended to have a higher overall hospital admission rate but a lower admission rate for surgical episodes, and they generally had a longer LOS although this difference was only greater than a day in three MDCs. Case fatality was higher in non-insured patients, but there was no systematic trend with regard to readmission rates. Conclusions: The study found that for all MDCs, other than those where treatment was required on an emergency basis, patients with private health insurance had improved access to surgical procedures. Either non-insured patients were disadvantaged in their access to surgery or the higher intervention rate in privately insured patients represented supplier-/consumer-induced demand which may not always have been to the patients advantage or both may have occurred.