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Hospital length of stay variation and comorbidity of mental illness: a retrospective study of five common chronic medical conditions


Siddiqui, N and Dwyer, M and Stankovich, J and Peterson, G and Greenfield, D and Si, L and Kinsman, L, Hospital length of stay variation and comorbidity of mental illness: a retrospective study of five common chronic medical conditions, BMC Health Services Research, 18 Article 498. ISSN 1472-6963 (2018) [Refereed Article]

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© The Author(s). 2018. Licensed under Creative Commons Attribution 4.0 International (CC BY 4.0)

DOI: doi:10.1186/s12913-018-3316-2


Background: With the increasing burden of mental illness globally, it is becoming common for hospitalised patients with chronic medical conditions to have a comorbidity of mental illness. This combination could prolong length of stay (LOS) of this patient cohort. We conducted an investigation in Tasmania, Australian hospitals to characterise this cohort and assess if co-morbidity of mental illness is a distinguishing factor that generates LOS variation across different chronic medical conditions.

Methods: The retrospective study analysed 16,898 admissions of patients with a primary diagnosis of one of five chronic medical conditions: lung or colorectal cancer, chronic obstructive pulmonary disease (COPD), type II diabetes, ischaemic heart disease (IHD) and stroke. Data were from July 2010 to June 2015, across four hospitals that collectively cover 95% of public hospital admissions in Tasmania, Australia. Descriptive statistics were used to compare characteristics of patients between the scenarios of with and without co-morbidity of mental illness. We used negative binomial regression models to assess whether co-morbidity of mental illness, along with its subtypes, after adjustment for potential confounding variables, associated with LOS variation in patients of each medical condition. Based on the adjusted LOS variation, we estimated differences in bed days’ use between patients with and without comorbidity of mental illness.

Results: Patients with co-morbidity of mental illness were significantly younger in comparison to patients without mental illness. With each medical condition, patients with comorbidity of mental illness had incurred higher bed days’ use than for those without mental illness. In cancer and stroke cohorts, co-morbidity of mental illness unfavourably affected the LOS variation by as high as 97% (CI: 49.9%–159%) and 109% (78%–146%), respectively. Though mental and behavioural disorders due to psychoactive substances was a dominant sub-type of mental illness across the medical conditions, it contributed significant unfavourable LOS variation only in the stroke patients i.e. 36.3% (CI: 16.2%–59.9%).

Conclusions: Mental illness consistently produced unfavourable LOS variation. Upskilling of healthcare teams and greater reporting and analysis of LOS variation for this patient cohort, and the sub-cohorts within it, are necessary to provide improved medical care and achieve system efficiencies.

Item Details

Item Type:Refereed Article
Keywords:mental health, demand, crowding, comorbidities, LOS variation, hospital
Research Division:Health Sciences
Research Group:Health services and systems
Research Field:Mental health services
Objective Division:Health
Objective Group:Public health (excl. specific population health)
Objective Field:Mental health
UTAS Author:Siddiqui, N (Dr Nazlee Siddiqui)
UTAS Author:Dwyer, M (Dr Mitchell Dwyer)
UTAS Author:Stankovich, J (Dr Jim Stankovich)
UTAS Author:Peterson, G (Professor Gregory Peterson)
UTAS Author:Greenfield, D (Professor David Greenfield)
UTAS Author:Kinsman, L (Professor Leigh Kinsman)
ID Code:126849
Year Published:2018
Web of Science® Times Cited:14
Deposited By:Health Sciences
Deposited On:2018-06-28
Last Modified:2018-11-29
Downloads:120 View Download Statistics

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