Using linked health and social care data to monitor dementia incidence and evaluate dementia care in Australia

Abstract

Dementia is a leading cause of disability affecting approximately 50 million people worldwide. Currently, in Australia, there is no optimum way of monitoring the incidence or prevalence of dementia at the population level. There are also many unanswered questions regarding crucial aspects of dementia care, such as whether the provision of home-based services can reduce the time spent in residential care. Routinely collected administrative data have the potential to fill these gaps.

This thesis explores the use of linked administrative data for detecting and monitoring dementia in Australia, uses these data to understand the care pathways followed by people with dementia, and addresses policy-focused questions aimed at improving dementia care. It does so by presenting the results of four research studies using the 45 and Up Study, a cohort of 267,153, recruited in 2006-2009 in New South Wales, Australia. The 45 and Up baseline survey was linked to a range of administrative datasets including records of hospitalisations, emergency department visits, aged care assessments, and claims for pharmaceuticals, medical services, aged care services and deaths for the period 2006-2016.

Key findings include: (i) measuring dementia incidence with multiple linked administrative datasets identifies almost 80% of expected dementia cases (92% for those aged 80-84 years) and produces age-specific incidence rates that mirror those based on clinical diagnosis; (ii) entering residential care is the norm among people with dementia, and home-based care may not be meeting their needs at end of life; (iii) high-level home care for people with dementia may reduce the subsequent time spent in residential care; and (iv) changing to a new general practitioner (GP) when entering residential care is related to increased polypharmacy and initiation of psychotropic medicines among people with dementia.

These findings will inform on-going efforts to monitor dementia incidence and care in Australia. They also have major policy implications, including emphasising the pressing need in Australia for more high-level home care packages, and highlighting end-of-life dementia care as a priority for policy development and innovation in service delivery. The link between GP continuity and psychotropic prescribing highlights a new intervention point that could assist in the efforts to reduce psychotropic prescribing in residential aged care.