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

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.