title: Clinical Outcomes Associated with Medication Regimen Complexity in Older People: A Systematic Review.
abstract: OBJECTIVE
  To systematically review clinical outcomes associated with medication regimen complexity in older people.
  
  
  METHODS
  Systematic review of EMBASE, MEDLINE, International Pharmaceutical Abstracts, Cumulative Index to Nursing and Allied Health Literature, and the Cochrane library.
  
  
  METHODS
  Hospitals, home, and long-term care.
  
  
  METHODS
  English-language peer-reviewed original research published before June 2016 was eligible if regimen complexity was quantified using a metric that considered number of medications and at least one other parameter, regimen complexity was calculated for participants' overall regimen, at least 80% of participants were aged 60 and older, and the study investigated a clinical outcome associated with regimen complexity.
  
  
  METHODS
  Quality assessment was conducted using an adapted version of the Joanna Briggs Institute critical appraisal tool.
  
  
  RESULTS
  Sixteen observational studies met the inclusion criteria. Regimen complexity was associated with medication nonadherence (2/6 studies) and higher rates of hospitalization (2/4 studies). One study found that participants with less-complex medication administration were more likely to stop medications when feeling worse. One study each identified an association between regimen complexity and higher ability to administer medications as directed, medication self-administration errors, caregiver medication administration hassles, hospital discharge to non-home settings, postdischarge potential adverse drug events, all-cause mortality, and lower patient knowledge of their medication. Regimen complexity had no association with postdischarge medication modification, change in medication- and health-related problems, emergency department visits, or quality of life as rated by nursing staff.
  
  
  CONCLUSIONS
  Research into whether medication regimen complexity is associated with nonadherence and hospitalization has produced inconsistent results. Moderate-quality evidence from four studies (two each for nonadherence and hospitalization) suggests that medication regimen complexity is associated with nonadherence and higher rates of hospitalization.
authors.affiliation: Centre for Medicine Use and Safety, Faculty of Pharmacy and Pharmaceutical Sciences, Monash University, Melbourne, Victoria, Australia.|Division of Pharmacy, School of Medicine, Faculty of Health, University of Tasmania, Hobart, Tasmania, Australia.
authors.forename: Barbara C
authors.initials: BC
authors.lastname: Wimmer
authors.affiliation: Centre for Medicine Use and Safety, Faculty of Pharmacy and Pharmaceutical Sciences, Monash University, Melbourne, Victoria, Australia.
authors.forename: Amanda J
authors.initials: AJ
authors.lastname: Cross
authors.affiliation: Centre for Medicine Use and Safety, Faculty of Pharmacy and Pharmaceutical Sciences, Monash University, Melbourne, Victoria, Australia.
authors.forename: Natali
authors.initials: N
authors.lastname: Jokanovic
authors.affiliation: Sansom Institute, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Wiese
authors.affiliation: Centre for Medicine Use and Safety, Faculty of Pharmacy and Pharmaceutical Sciences, Monash University, Melbourne, Victoria, Australia.
authors.forename: Johnson
authors.initials: J
authors.lastname: George
authors.affiliation: Aging Research Center, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet and Stockholm University, Stockholm, Sweden.
authors.forename: Kristina
authors.initials: K
authors.lastname: Johnell
authors.affiliation: Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria, Australia.
authors.forename: Basia
authors.initials: B
authors.lastname: Diug
authors.affiliation: Centre for Medicine Use and Safety, Faculty of Pharmacy and Pharmaceutical Sciences, Monash University, Melbourne, Victoria, Australia.|Sansom Institute, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia.|Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria, Australia.
authors.forename: J Simon
authors.initials: JS
authors.lastname: Bell
mesh_terms: D000368:Aged; D002423:Cause of Death; D015897:Comorbidity; D064420:Drug-Related Side Effects and Adverse Reactions; D006760:Hospitalization; D006801:Humans; D055118:Medication Adherence; D008508:Medication Errors; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D019338:Polypharmacy; D012307:Risk Factors
keywords: adherence; aged; medication regimen complexity; systematic review