4.1 Main Findings
Residents with polypharmacy were more likely to be prescribed at least one analgesic such as paracetamol or an opioid, a laxative, antidepressant, antithrombotic agent, drug for peptic ulcer and GORD, diuretic, lipid-modifying agent and beta-blocking agent. Antipsychotic use was not associated with polypharmacy. Between 74 and 96% of LTCFs fell within the 95% control limits of the mean for each of the most prevalent medication classes. Facilities with a high prevalence of polypharmacy were primarily from the same health service, were smaller and had a higher prevalence of each medication class, with the exception of antipsychotics.
This study found 36% of residents were charted nine or more regular medications. In comparison, our systematic review of the international literature found from 12.8 to 74.4% of residents in LTCFs receive nine or more medications [
3]. The wide variability may reflect the inclusion or exclusion of as-needed medications, topical formulations and vitamins and herbal preparations. This poses challenges when comparing the prevalence of polypharmacy between studies [
3]. Although polypharmacy is not synonymous with potentially inappropriate medication use, residents with polypharmacy are more likely to use potentially inappropriate medications [
27]. Interventions targeting the reduction of unnecessary or inappropriate medication use, and subsequently polypharmacy, are likely to benefit residents in LTCFs.
4.2 Which Medications Contribute to Polypharmacy?
Diuretics, beta-blocking agents, antithrombotic agents (e.g. aspirin) and lipid-modifying agents (e.g. statins) were strongly associated with polypharmacy. This was consistent with the findings of Bronskill et al. [
5], who reported that five of the ten most prevalent medications in LTCFs were cardiovascular medications. Clinical practice guidelines provide limited guidance for the management of chronic disease among people with multimorbidity in the LTCF setting [
28]. Polypharmacy may arise because clinicians extrapolate evidence from disease-specific research conducted among younger people in community settings. This is particularly the case for cardiovascular guidelines, which provide limited guidance for older people [
29,
30].
Almost three-quarters (71.7%) of residents with polypharmacy were prescribed a medication for GORD, primarily proton-pump inhibitors (PPIs). Recent studies in the USA have found almost half of residents are prescribed a PPI without an evidence-based indication [
31,
32]. This is a concern because frail older residents may be particularly susceptible to harms associated with the long-term use of PPIs, including fractures, pneumonia and vitamin and mineral deficiencies [
33]. There is a need for regular review of PPIs in LTCFs with a view to cease treatment in residents without an ongoing therapeutic need [
34].
Residents with polypharmacy were less likely to have a dementia diagnosis or use antipsychotics. This was consistent with findings reported in a recent systematic review of polypharmacy in LTCFs, which found an inverse association between cognitive impairment and polypharmacy (three of four studies) [
3]. Several studies have identified the need to avoid or discontinue medications that may impair cognition in people with coexisting cognitive impairment [
35,
36]. The lower prevalence of polypharmacy among residents with dementia may reflect medication discontinuation or ‘deprescribing’ in residents with advanced dementia [
37]. The high prevalence of swallowing difficulties among residents with dementia may provide an incentive for clinicians to discontinue unnecessary medications.
The high prevalence of analgesic use among residents with polypharmacy may reflect increased awareness that pain has been under-recognized and under-treated in LTCFs. The prevalence of pain may be as high as 80%, and this may explain the increasing use of analgesics over the last decade [
38‐
40]. This study found 67% of all residents were charted paracetamol and 34% were charted an opioid regularly, which was consistent with other recent Australian studies [
41,
42] but higher than reported internationally [
39,
43]. Although the high prevalence of regular analgesic use suggests improved treatment of pain, its appropriateness is uncertain. Opioids were twice as prevalent among residents with polypharmacy as those without, and opioid use may necessitate co-prescribing of laxatives. The appropriateness of long-term opioid use in older people should be considered in light of potential harms, including falls and fractures, and limited evidence for safety and efficacy in frail older people [
44].
Over half (63.6%) of residents with polypharmacy were prescribed antidepressants; however, fewer than half (44.2%) of residents with polypharmacy had a documented diagnosis of depression. It is possible that antidepressants were prescribed for other indications, including pain or insomnia. In contrast to a previous study [
45], residents with polypharmacy in this study were less likely to be charted an antipsychotic. Antipsychotic use has been reported in up to one-third of residents with dementia in LTCFs [
46,
47]. Polypharmacy was found to be inversely associated with dementia diagnosis in this study, which could partially explain the lower prevalence of antipsychotic use in residents with polypharmacy. In addition, the recognition of antipsychotic ADEs such as falls and mortality [
48], and the introduction of initiatives to minimize antipsychotic use in dementia may also contribute [
49‐
51].
4.3 Variability of Medications Contributing to Polypharmacy Across LTCFs
A wide variation in the prevalence of polypharmacy and in all medications classes, with the exception of other analgesics and antipyretics, was reported across the 27 LTCFs. However, the majority of facilities had fewer than 40 beds, which may contribute to the wide variability in medications seen across facilities. The variability seen in medications often used for symptomatic relief, such as high-ceiling diuretics, is likely to reflect variability in the degree of disability between residents. There was greater facility-to-facility variation in the use of antipsychotics, ranging from no regular use to 95% in one facility. However, the LTCFs included in our project encompassed a mix of both general and psychogeriatric aged care services. In addition to prescriber variability, a number of facility-level factors, including facility type and staffing levels, have been found to be associated with variability in antipsychotic use in LTCFs [
13‐
16].
Between 7 and 23% of facilities fell outside the 95% control limits of the mean for the most prevalent medication classes, indicating inter-facility variability in the prescribing of these medications. The greatest variability between LTCFs was found for medications for constipation and antithrombotic agents, which were found to have 26 and 19% of facilities falling outside these control limits, respectively. Inter-facility variability in the prescribing of laxatives may be associated with differences in residents’ level of disability and health status, including the ability to communicate their symptoms to staff [
52]. Guidance for the use of antithrombotic agents, including the use of aspirin, is limited in older people and may require a risk versus benefit assessment in individual residents.
The facilities included in this study were relatively small, with ten facilities housing fewer than 15 residents. Facilities with a high prevalence of polypharmacy (defined as ≥ 50%) primarily had fewer than 20 residents and were located within the same health service. Prescribing may have been performed by a small number of GPs or a single GP. The Victorian Government DHHS has identified a number of strategies to address polypharmacy, three of which are currently being implemented [
53]. These include three new medication sub-indicators, creation of ‘deprescribing scripts’ to improve provider–resident communication about medication cessation, and optimizing the role of medication advisory committees.
4.4 Strengths and Limitations
It was a strength that data were obtained from all residents across 27 LTCFs in regional and rural Victoria, Australia, by trained members of the research team and nursing staff. Pilot testing of the standardized data collection tool and data extraction was performed by the research team to ensure consistency and accuracy among data collectors and extractors. Medical diagnoses were obtained from the clinical diagnoses recorded in each resident’s medical records. Data obtained from medical records were dependent on complete and accurate recording by clinicians in the medical record, which may have been incomplete. We did not have access to information on individual residents’ disease severity, goals of care or estimated life expectancy, which are important factors related to the pattern of prescribing in this setting.
The study was conducted in rural and regional areas and therefore the findings may not be generalizable to metropolitan settings. This study did not investigate prescriber- or facility-related (e.g. organizational culture) factors in addition to facility size, which may have contributed to the variability in polypharmacy across facilities. Additional studies are required to further explore resident-, prescriber- and facility factors that may have contributed to the variability in polypharmacy found across facilities. Funnel plots were created to account for facility size. The clinical appropriateness of polypharmacy and adherence to recommended clinical practice guidelines was not assessed in the present study and should be considered in future studies to determine whether interventions are needed to address polypharmacy. We could not determine whether the variability of polypharmacy across facilities in our study reflects suboptimal care. However, because common medications, both appropriate and potentially inappropriate, are more prevalent in residents with polypharmacy, it would be prudent to target individualized interventions to improve quality and safety to those facilities with unexplained rates of polypharmacy. Future research should focus on better understanding the risks associated with specific medications that are more prevalent in residents with polypharmacy. A recent case–control study reported that medications causing orthostatic hypotension, rather than polypharmacy itself, were associated with an increased risk of fall-related hospital admissions, although this risk was highest in residents with polypharmacy [
54]. Longitudinal studies are needed to further explore the temporal change in medication use in LTCFs.