An examination of inpatient ward and secondary community care stay costs for individuals with complex mental health needs in the UK.

Some people with mental health problems have such high levels of complex clinical and/or risk needs that those needs cannot be adequately met within generic mental health services. To design health and social provisions to better serve these people's needs, it is necessary to first characterise the current provision. This study examines the cost element of this provision. This retrospective observational cohort study examined routinely collected healthcare service administrative data from a large UK-based NHS provider of community and hospital-based mental health services. Data were collected from medical records of individuals with complex mental health (CMH) needs aged ≥18 years old who had an inpatient ward stay between February 2000 until August 2021. Predictors of annual inpatient ward and secondary community care stay (residential/supported living/independent) costs were estimated using generalised linear models. Mean (median) annual total healthcare costs for 185 included adults were £106,847 (£109,651), comprising 16.4% from inpatient ward stay costs of £17,512 (£10,723) and 83.6% from secondary community care stay costs of £89,336 (£97,739). Associations varied across care context. Key predictors of inpatient stay cost included age, deprivation, and substance abuse. The primary diagnostic group of schizophrenia, schizotypal and delusional disorders (ICD10 codes: F20-F29) was found to be a predictor of greater secondary community care stay costs. Inpatient ward and secondary community care stay costs varied across patient characteristics. Additional research is warranted to further explore predictors identified in this study to prevent, promote, and monitor activities for individuals with differing CMH needs.