Background: People with mental disorders have increased health service use, a higher frequency of hospitalisation and longer admissions than the general population.
Objectives: To identify clinical characteristics of patients with repeat mental health (MH) admissions and determine whether the clinical characteristics vary across admission thresholds within a 12-month period of high use.
Methods: Retrospective longitudinal study of hospital admissions for MH, among residents aged 18 years and older admitted with a mental disorder as a principal diagnosis to Illawarra Shoalhaven Local Health District (ISLHD) hospitals between 1 January 2012 and 31 December 2016. Diagnostic subgroups were substance use, mood, neurotic, schizophrenia, personality, behavioural and self- harm disorder.
Findings: Of the 5631 people in the study, 50.9% had at most one admission and 25.4% had at most two admissions in any 12-month period. Mood disorder was the most prevalent principal diagnosis (26.0%), followed by neurotic disorders (25.6%), substance use disorders (23.7%) and schizophrenia (19.3%). Patients with schizophrenia had the highest number of admissions (mean, 2.6) and bed days (mean, 56.2). The percentage of people with schizophrenia doubled among those with one compared to four admissions (13.9���28.0%); however, the percentage of people with neurotic disorders halved at these same thresholds (30.9���14.0%).
Conclusion: Identifying characteristics of people with MH problems and high health service utilisation at various thresholds of admissions requires a longitudinal perspective. Evidence on clinical characteristics can support service providers and policymakers to understand patterns of repeat MH admission, and whether alternative models of care are required.