title: Medication regimen complexity and readmissions after hospitalization for heart failure, acute myocardial infarction, pneumonia, and chronic obstructive pulmonary disease.
abstract: OBJECTIVE
  Readmission rate is increasingly being viewed as a key indicator of health system performance. Medication regimen complexity index scores may be predictive of readmissions; however, few studies have examined this potential association. The primary objective of this study was to determine whether medication regimen complexity index is associated with all-cause 30-day readmission after admission for heart failure, acute myocardial infarction, pneumonia, or chronic obstructive pulmonary disease.
  
  
  METHODS
  This study was an institutional review board-approved, multi-center, case-control study. Patients admitted with a primary diagnosis of heart failure, acute myocardial infarction, pneumonia, or chronic obstructive pulmonary disease were randomly selected for inclusion. Patients were excluded if they discharged against medical advice or expired during their index visit. Block randomization was utilized for equal representation of index diagnosis and site. Discharge medication regimen complexity index scores were compared between subjects with readmission versus those without. Medication regimen complexity index score was then used as a predictor in logistic regression modeling for readmission.
  
  
  RESULTS
  Seven hundred and fifty-six patients were randomly selected for inclusion, and 101 (13.4%) readmitted within 30 days. The readmission group had higher medication regimen complexity index scores than the no-readmission group (p < 0.01). However, after controlling for demographics, disease state, length of stay, site, and medication count, medication regimen complexity index was no longer a significant predictor of readmission (odds ratio 0.99, 95% confidence interval 0.97-1.01) or revisit (odds ratio 0.99, 95% confidence interval 0.98-1.02).
  
  
  CONCLUSIONS
  There is little evidence to support the use of medication regimen complexity index in readmission prediction when other measures are available. Medication regimen complexity index may lack sufficient sensitivity to capture an effect of medication regimen complexity on all-cause readmission.
authors.affiliation: Department of Pharmacy Services, Sharp Memorial Hospital, San Diego, CA, USA; Department of Clinical Sciences, Touro University California College of Pharmacy, Vallejo, CA, USA.
authors.forename: Nada
authors.initials: N
authors.lastname: Abou-Karam
authors.affiliation: Department of Pharmacy Services, Sharp Memorial Hospital, San Diego, CA, USA; Department of Clinical Sciences, Touro University California College of Pharmacy, Vallejo, CA, USA.
authors.forename: Chad
authors.initials: C
authors.lastname: Bradford
authors.affiliation: Department of Clinical Sciences, Touro University California College of Pharmacy, Vallejo, CA, USA.
authors.forename: Kajua B
authors.initials: KB
authors.lastname: Lor
authors.affiliation: Department of Clinical Sciences, Touro University California College of Pharmacy, Vallejo, CA, USA.
authors.forename: Mitchell
authors.initials: M
authors.lastname: Barnett
authors.affiliation: College of Pharmacy, Western University of Health Sciences, Pomona, CA, USA.
authors.forename: Michelle
authors.initials: M
authors.lastname: Ha
authors.affiliation: System Pharmacy Services, Sharp Healthcare, San Diego, CA, USA.
authors.forename: Albert
authors.initials: A
authors.lastname: Rizos
keywords: Medication regimen complexity index; acute care utilization; high-risk disease state; re-hospitalization; readmission