Risk factors and direct medical cost of early versus late unplanned readmissions among diabetes patients at a tertiary hospital in Singapore

Abstract

Objective: To examine the risk factors and direct medical costs associated with early (≤30 days) versus late (31–180 days) unplanned readmissions among patients with type 2 diabetes in Singapore.

Methods: Risk factors and associated costs among diabetes patients were investigated using electronic medical records from a local tertiary care hospital from 2010 to 2012. Multivariable logistic regression was used to identify risk factors associated with early and late unplanned readmissions while a generalized linear model was used to estimate the direct medical cost. Sensitivity analysis was also performed.

Results: A total of 1729 diabetes patients had unplanned readmissions within 180 days of an index discharge. Length of index stay (a marker of acute illness burden) was one of the risk factors associated with early unplanned readmission while patient behavior-related factors, like diabetes-related medication adherence, were associated with late unplanned readmission. Adjusted mean cost of index admission was higher among patients with unplanned readmission. Sensitivity analysis yielded similar results.

Conclusions: Existing routinely captured data can be used to develop prediction models that flag high risk patients during their index admission, potentially helping to support clinical decisions and prevent such readmissions.

Keywords:

• Readmission
• unplanned
• diabetes
• cost
• risk factor

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Declaration of funding

This manuscript was not funded.

Author contributions: M.E.P., J.Y., C.C. and H.L.W. were involved in the conception and design of the study. M.E.P. analyzed the data while M.E.P., J.Y., H.L.W. and E.S.T. were involved in the interpretation of the data. M.E.P. and J.Y. were involved in the drafting of the paper. All authors agree to be accountable for all aspects of the work. All authors critically revised the manuscript for intellectual content, agreed to be accountable for all aspects of the work and provided the final approval of the version to be published.

Declaration of financial/other relationships

M.E.P., J.Y., C.C., C.S.T., E.S.T., E.Y.H.K. and H.L.W. have disclosed that they have no significant relationships with or financial interests in any commercial companies related to this study or article.

CMRO peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Acknowledgements

We would like to thank Mr. Mark Kevin Salloway from the Saw Swee Hock School of Public Health, National University of Singapore and Mr. Kok Joon Chong from the Department of Medicine, National University Hospital for their support in data management for this study.