Introduction
Medication-related harm is an underdiagnosed problem in Australia,1 costing the Australian healthcare system about A$1.4 billion per annum.2 The older population (aged ≥65 years) is particularly vulnerable to medication-related harm due to their advanced age, multimorbidity and increased use of medications (polypharmacy).3 Increased medication use is, in turn, linked to potentially inappropriate prescribing (PIP).4,5 Potentially inappropriate prescribing comprises the use of potentially inappropriate medications (PIMs) where the risks outweigh clinical benefits and potential prescribing omissions (PPOs), which is the failure to prescribe medications that provide benefits.6Recent reviews have shown that PIPs are common among older adults in diverse healthcare settings, and are associated with medication-related hospitalisation, adverse drug reactions, adverse drug events, and functional decline.7,8 A systematic review and meta-analysis of 63 included studies has shown that patients using at least 1 PIM in the inpatient setting (compared with non-users) were associated with a 91% increased odds of medication-related hospital admission, and 60% increased odds of dependency in at least 1 activity of daily living.7
Multiple screening tools are available to detect and reduce PIPs among older adults, such as the Screening Tool of Older Person’s Prescriptions and the Screening Tool to Alert doctors to Right Treatment (STOPP/START) criteria, and the Beers criteria.9 These are also the tools commonly used in research in Australian healthcare setting.10-14 PIP, according to STOPP/START criteria, have been investigated mainly through retrospective analysis in acute care settings,11-13 with high variability in prevalence estimates between care transition points. A clinical audit of electronic medical records of 249 older people from an Australian teaching hospital found 51% were exposed to at least 1 PIM at hospital admission and, this prevalence was reduced to 37% at discharge.12 In contrast, another Australian study found an increase in the prevalence of PIM use from hospital admission to discharge (54.8% vs 60.8%).13 In addition, results from previous international studies on the influence of inappropriate prescribing on post-discharge health outcomes are mixed. While some studies highlighted the presence of PIMs/PPOs was significantly associated with potentially preventable medication-related hospital admissions,15repeated hospital admissions and mortality,16 other investigations did not confirm these findings with respect to post-discharge health outcomes, including rehospitalization and mortality either in acute care17-19 or geriatric rehabilitation settings.20 Moreover, evidence is limited on PIM/PPO prevalence as well as their associations with post-discharge health outcomes in patients admitted to and discharged from geriatric rehabilitation settings.
The purpose of this study was to assess the prevalence of PIM and PPO use at transitions of geriatric rehabilitation care (acute admission, admission to and discharge from geriatric rehabilitation) and to investigate the associations between PIMs, PPOs, and number of medications identified at discharge from geriatric rehabilitation with subsequent post-discharge health outcomes, including hospital readmissions and mortality.