Antimicrobial prescribing in aged care continues to rise

antimicrobial

While Australians are taking fewer antibiotics overall, there are concerns that antimicrobial prescribing is steadily increasing in aged care.

Each year, the Australian Commission on Safety and Quality in Health Care’s Antimicrobial use in the community (AURA) report analyses antimicrobials supplied under the Pharmaceutical Benefits Scheme (PBS) and Repatriation PBS (RPBS) – featuring both antimicrobial use in aged care and by local area.

The latest report, AURA 2023 found that although there has been a small increase of 1.3%  in overall antimicrobial use in the community from 2022 to 2023, use is still 24.4% lower than in 2015. 

Alarmingly, there has been a stark 11.1% increase in antimicrobial use in residents of aged care homes from 2022 to 2023.

Antimicrobial use is also considerably higher for older Australians who reside in aged care homes than for those living in the community. While just over a third of Australians had at least one antimicrobial dispensed, almost three-quarters of residential aged care facility (RACF) residents received at least one antimicrobial prescription last year.

Australian Pharmacist looks at which antibiotics are most commonly prescribed in aged care, the impacts of high antimicrobial use, and what pharmacists can do to help.

Why is antibiotic prescribing in aged care so high?

There are several reasons why RACF antimicrobial prescribing is higher than in the rest of the community. 

Professor John Turnidge AO

According to infectious diseases physician and microbiologist Professor John Turnidge AO, Senior Medical Advisor, Australian Commission on Safety and Quality in Health Care, these include:

  • increased incidence of infections due to advanced aged
  • multiple comorbidities 
  • poor functional status
  • compromised immune status
  • the presence of medical devices, such as urinary catheters that give bacteria direct access into the body.
‘RACFs are [also] often close-living environments, which means residents are likely to be in frequent contact with other residents, staff or visitors who are potentially colonised or infected,’ he said.

Furthermore, antimicrobial prescribing in aged care is often not consistent with guidelines. For example the management of asymptomatic bacteriuria, a common condition in the elderly that is often mistaken for an active urinary tract infection (UTI) that needs antimicrobial treatment and ongoing management, said Prof Turnidge.

‘Among aged care residents, it can also be challenging to distinguish bacterial infection from other diagnoses, which contributes to empirical prescribing as a precaution,’ he added.

Along with UTIs, successive aged care National Antimicrobial Prescribing Survey reports have identified respiratory infections and skin conditions as the most common indications for prescribing antimicrobials for aged care residents, said Prof Turnidge.

‘These conditions are prevalent among the elderly due to age-related physiological changes and comorbid health issues,’ he said.

What antibiotic is most commonly prescribed?

In 2023, cefalexin was the most frequently dispensed antimicrobial in RACFs, as well in the general community, due to its activity against a range of bacteria that cause common infections affecting aged care residents and a generally favourable adverse effect profile, said Prof Turnidge.

Around two-thirds of Australians aged 75 years and over take five or more medicines, so prescribers may also choose cefalexin because it has minimal drug interactions, reducing the risk of complications, he said.

However, over-reliance on cefalexin can lead to the development of resistant bacterial strains. 

‘This is an issue for many bacteria including some strains of Staphylococcus aureus (MRSA), which causes skin infections, and Escherichia coli, which causes UTIs,’ said Prof Turnidge.

What impact is this having on antimicrobial resistance?

Because antimicrobial prescribing in aged care reflects a high rate of antimicrobial use that’s not consistent with guidelines, this heightens the development and spread of antimicrobial-resistant infections, said Prof Turnidge.

‘Higher rates of resistance in RACFs have been found in other national surveillance programs, such as the Australian Passive AMR Surveillance program currently managed by the Commission,’ he said. 

Antimicrobial resistance compromises the effectiveness of available antimicrobials and can lead to more complex and costly treatments, including hospitalisation, because no effective oral treatments are available. 

‘As antimicrobials become ineffective, it really limits the options for people who need treatment, such as surgery or chemotherapy,’ said Prof Turnidge.

What is the pharmacist’s role in antimicrobial stewardship?

Since 1 July 2024, funding has been made available for community pharmacies and aged care providers to employ on-site pharmacists in RACFs through the Aged Care On-site Pharmacist (ACOP) program.

This provides on-site pharmacists greater opportunities to conduct regular medication reviews to ensure antimicrobial prescribing is appropriate and aligned with guidelines, said Prof Turnidge.

‘Pharmacists have a role in advocating for antimicrobial stewardship (AMS) to guide appropriate use,’ he added. 

To that end, on-site pharmacists can serve as knowledge brokers and clinical leaders to advise, mentor and empower staff towards better AMS, said Kirolos Wasef MPS, in-house credentialed pharmacist for Goodwin Aged Care Services in Canberra.

‘They can lead the AMS Committee to achieve tangible outcomes,’ he said. ‘On-site pharmacists can [also] lead quality improvement activities such as the “To Dip or Not to Dip” initiative to help reduce inappropriate use of antimicrobials.’

On-site pharmacists can also provide education to registered nurses about common AMS issues and how to prevent them, said Mr Wasef.

‘They [can] conduct audits and monitor prescribed antimicrobials to ensure appropriate indication and duration of use,’ he said.