title: Predicting frequent hospital admission risk in Singapore: a retrospective cohort study to investigate the impact of comorbidities, acute illness burden and social determinants of health.
abstract: To evaluate the impact of comorbidities, acute illness burden and social determinants of health on predicting the risk of frequent hospital admissions.
  
  
  
  Multivariable logistic regression was used to associate the predictive variables extracted from electronic health records and frequent hospital admission risk. The model's performance of our predictive model was evaluated using a 10-fold cross-validation.
  
  
  
  A single tertiary hospital in Singapore.
  
  
  
  All adult patients admitted to the hospital between 1 January 2013 and 31 May 2014 (n=25 244).
  
  
  
  Frequent hospital admissions, defined as 3 or more inpatient admissions within 12 months of discharge. Area under the receiver operating characteristic curve (AUC) of the predictive model, and the sensitivity, specificity and positive predictive values for various cut-offs.
  
  
  
  4322 patients (17.1%) met the primary outcome. 11 variables were observed as significant predictors and included in the final regression model. The strongest independent predictor was treatment with antidepressants in the past 1 year (adjusted OR 2.51, 95% CI 2.26 to 2.78). Other notable predictors include requiring dialysis and treatment with intravenous furosemide during the index admission. The predictive model achieved an AUC of 0.84 (95% CI 0.83 to 0.85) for predicting frequent hospital admission risk, with a sensitivity of 73.9% (95% CI 72.6% to 75.2%), specificity of 79.1% (78.5% to 79.6%) and positive predictive value of 42.2% (95% CI 41.1% to 43.3%) at the cut-off of 0.235.
  
  
  
  We have identified several predictors for assessing the risk of frequent hospital admissions that achieved high discriminative model performance. Further research is necessary using an external validation cohort.
authors.affiliation: Department of Family Medicine & Continuing Care, Singapore General Hospital, Singapore, Singapore Family Medicine Program, Duke-NUS Medical School, Singapore, Singapore.
authors.forename: Lian Leng
authors.identifier: 0000-0003-4228-2862
authors.initials: LL
authors.lastname: Low
authors.affiliation: Singapore Health Services, Health Services Research Centre, Singapore, Singapore Centre for Quantitative Medicine, Duke-NUS Medical School, Singapore, Singapore Department of Emergency Medicine, Singapore General Hospital, Singapore, Singapore.
authors.forename: Nan
authors.initials: N
authors.lastname: Liu
authors.affiliation: Integrated Health Information Systems, Singapore, Singapore.
authors.forename: Sijia
authors.initials: S
authors.lastname: Wang
authors.affiliation: Singapore Health Services, Health Services Research Centre, Singapore, Singapore Department of Rheumatology and Immunology, Singapore General Hospital, Singapore, Singapore.
authors.forename: Julian
authors.initials: J
authors.lastname: Thumboo
authors.affiliation: Department of Emergency Medicine, Singapore General Hospital, Singapore, Singapore Health Services and Systems Research, Duke-NUS Medical School, Singapore, Singapore.
authors.forename: Marcus Eng Hock
authors.initials: ME
authors.lastname: Ong
authors.affiliation: Department of Family Medicine & Continuing Care, Singapore General Hospital, Singapore, Singapore Family Medicine Program, Duke-NUS Medical School, Singapore, Singapore.
authors.forename: Kheng Hock
authors.initials: KH
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015897:Comorbidity; D017281:Cost of Illness; D005260:Female; D006801:Humans; D007297:Inpatients; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010343:Patient Admission / Q000706:statistics & numerical data*; D010359:Patient Readmission / Q000706:statistics & numerical data*; D012372:ROC Curve; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012680:Sensitivity and Specificity; D012846:Singapore; D064890:Social Determinants of Health; D062606:Tertiary Care Centers
keywords: Frequent hospital admission; comorbidities; depression; illness burden; readmission; social determinants of health