Public mental health service use by people with intellectual disability in New South Wales and its costs

Abstract

Objectives: To describe the population characteristics of people with intellectual disability in New South Wales; to quantify and compare public mental health service use and costs for people with and without intellectual disability in NSW during 2014-15.

Design: Retrospective cohort data linkage analysis.

Setting, participants: People using publicly funded in- or outpatient (admitted or non-admitted) mental health services in NSW, 2014-15.

Main outcome measures: Numbers of bed days (inpatient mental health services), and treatment days (ambulatory mental health); costs of publicly funded mental health services.

Results: People with intellectual disability comprised 1.1% of the NSW population, but 6.3% of people who used public mental health services; 12% of public mental health costs during 2014-15 were for people with intellectual disability. Compared with metropolitan local health districts (LHDs), overall public mental health service costs were lower for rural and regional LHDs (adjusted incidence rate ratio [aIRR], 0.8; 95% CI, 0.8-0.9) and higher for specialty networks (aIRR, 1.2; 95% CI, 1.1-1.3). Per person costs for people with intellectual disability were higher than for those without intellectual disability (aIRR, 2.6; 95% CI, 2.2-3.0).

Conclusion: People with intellectual disability use public mental health services to a greater degree than other people. They should be explicitly considered by all tiers of mental health policy and service planning in Australia. Population health planning for the needs of people with disabilities would be assisted by including disability identifiers in all health administrative data sets.

Keywords: Mental health policy; Mental health services.