To estimate dementia incidence rates using Australian administrative datasets and compare the characteristics of people identified with dementia across different datasets. This data linkage study used a cohort of 267,153 from the Australian 45 and Up Study. Participants completed a survey in 2006-2009 and subsequent dementia was identified through pharmaceutical claims, hospitalisations, aged care eligibility assessments, care needs at residential aged care entry and death certificates. Agespecific, and age-standardised incidence rates, incidence rate ratios and survival from first dementia diagnosis were estimated. Estimated age-standardised dementia incidence rates using all linked datasets was 16.8 cases per 1000 person years for people aged 65+. Comparing incidence rates to the global published rates suggested 77% of cases were identified but this varied by age with highest coverage among those aged 80-84 years (92%). Incidence rate ratios were inconsistent across datasets for: sex, socioeconomic disadvantage, size of support network, marital status, functional limitations and diabetes. Median survival from first dementia diagnosis ranged from 1.80 years in the care needs dataset to 3.74 years in the pharmaceutical claims dataset. Characteristics of people identified with dementia in different administrative datasets reflect the factors that drive interaction with specific services; this may introduce bias in observational studies using a single data-source to identify dementia. Routinely-collected linked administrative data are increasingly being used to monitor endpoints in observational studies and clinical trials 1. Dementia prevention studies may benefit from this approach due to the long time-frame required to study risk factors in this population 2. Within a research setting, maintaining contact with people in older age groups, particularly as they develop cognitive impairment or dementia is often not viable. Administrative data have the potential to increase power within studies by improving completeness of follow-up, and to reduce bias by avoiding the issue of differential drop-out due to cognitive impairment 3. However, there are also potential limitations to using administrative databases for detecting dementia. Administrative health data are those generated routinely via a person's interaction with the health system. They may include records of hospitalisation, physician visits, entry to long term care or dispensing of pharmaceuticals. They are generally collected with payment rather than research in mind, but there is often a degree of data curation that increases accuracy or adds value such as through coding of diseases and medical conditions. As such, they can be a valuable resource for research 4. When using such data to measure endpoints in trials or cohort studies it is important to consider both whether the cases identified have the disease of interest (usually indicated by high positive predictive value (PPV)) and the proportion of total cases that are detected (sensitivity). A recent syst...

IntroductionThere is no gold standard method for monitoring dementia incidence in Australia. Routinely collected linked administrative data are increasingly being used to monitor endpoints in observational studies and clinical trials and could benefit dementia research. Objectives and ApproachThis study examines dementia incidence within different Australian administrative datasets and how characteristics vary across datasets for groups detected as having dementia. This was an observational data linkage study based on a prospective cohort of 267,153 people in New South Wales, Australia from the 45 and Up Study. Participants completed a survey in 2006-2009 and dementia was identified using linked pharmaceutical claims (provided by Services Australia), hospitalisations, assessments of aged care eligibility, care needs at entry to residential aged care and death certificates. Data linkage was undertaken by the Centre for Health Record Linkage (CHeReL) and the Australian Institute of Health and Welfare. Age-specific and age-standardised incidence rates, incidence rate ratios and survival from first dementia diagnosis were calculated. ResultsAge-standardised dementia incidence was 16.9 cases per 1000 person years (PY) for people aged 65 years and over. Estimates for those aged 80-89 years were closest to published incidence rates (91% of rates for high-income countries). Relationships with dementia incidence were inconsistent across datasets for characteristics including sex, relative socio-economic disadvantage, support network size, marital status, functional limitations and diabetes. Median survival from first pharmaceutical claim for an anti-dementia medicine was 3.7 years compared to 3.0 years from first aged care eligibility assessment, 2.0 years from a dementia-related hospitalisation and 1.8 years from first residential aged care needs assessment. Conclusion / ImplicationsPeople identified with dementia in different administrative datasets have different characteristics, reflecting the factors that drive interaction with specific services. Bias may be introduced if single data sources are used to identify dementia as an outcome in observational studies.

Aim:To describe the characteristics of people in Central and Eastern Sydney (CES), NSW, who had a General Practice Management Plan (GPMP) and claimed for at least one private allied health service item; and to examine if allied health service use results in less hospitalisations over a five-year period.Background:The number of people living with chronic health conditions is increasing in Australia. The Chronic Disease Management programme was introduced to the Medicare Benefits Schedule (MBS) to provide a more structured approach to managing patients with chronic conditions and complex care needs. The programme supports general practitioners claiming up to one GPMP and one Team Care Arrangement every year, and the patient additionally claiming for up to five private allied health services visits.Methods:A prospective longitudinal study was conducted. The sample consisted of 5771 participants in CES who had a GPMP within a two-year health service utilisation baseline period (2007–2009). The analysis used the 45 and Up Study questionnaire data linked to the MBS, hospitalisation, death and emergency department data for the period 2006–2014.Findings:Of the eligible participants, 43% (2460) had at least one allied health service item claim in the subsequent 12 months. Allied health services were reported as physiotherapy, podiatry and other allied health services. The highest rates of allied health service use were among participants aged 85 years and over (49%). After controlling for confounding factors, a significant difference was found between having claimed for five or more physiotherapy services and emergency admissions (HR: 0.83; 95% CI: 0.72–0.95) and potentially preventable hospitalisations (HR: 0.79; 95% CI: 0.64–0.96) in the subsequent five years. Use of allied health service items was well targeted towards those with chronic and complex care needs, and use of physiotherapy services was associated with less avoidable hospitalisations.

Objective: To examine relationships between changing general practitioner after entering residential aged care and overall medicines prescribing (including polypharmacy) and that of psychotropic medicines in particular.Design: Retrospective data linkage study. Setting, participants: 45 and Up Study participants in New SouthWales with dementia who were PBS concession card holders and entered permanent residential aged care during January 2010 -June 2014 and were alive six months after entry.

The number of older people living with chronic health conditions is increasing in Australia. The Chronic Disease Management (CDM) items program was introduced to the Medicare Benefits Schedule (MBS) to encourage a more structured approach to managing patients with chronic conditions. Initial uptake was slow and recent research has suggested that uptake is decreasing. This paper examines: person MBS CDM claims in NSW between 2006 and 2014 — using baseline survey data (2006–09) from the Sax Institute’s 45 and Up Study linked to MBS and Death Registry data (2006–14) — and MBS CDM claims per 100000 population — using billing data sourced from the Medicare Australia Statistics website — to systematically examine any changes in uptake using a time-series analysis. After age adjustment, claims for initial plans increased from 11.3% in 2006 to 22.4% in 2014. Increases were also seen for allied health service claims (from 4.1% in 2006 to 20.8% in 2014) and for plan reviews (from 5.9% in 2006 to 16.0% in 2014). These increases were consistent with the MBS summary claims data. There is evidence that these plans are appropriately targeting those in most need; however, there is limited evidence of their effect. Claims for plan reviews, although increasing, are suboptimal and may indicate poor continuity of care.