Australian Polypharmacy Trends Between 2013 and 2024: A Repeated Cross-Sectional Study in the Adult Population

Area of Science:

• Gerontology and Public Health
• Pharmaceutical Sciences
• Epidemiology

Background:

• Polypharmacy, defined as the regular use of multiple medications, is a growing concern in aging populations.
• Understanding polypharmacy trends is crucial for public health planning and resource allocation.
• Gender differences in medication use and prevalence of polypharmacy require investigation.

Purpose of the Study:

• To estimate the prevalence and trends of polypharmacy and hyperpolypharmacy in Australian adults from 2013 to 2024.
• To analyze changes in polypharmacy prevalence by gender and age groups.
• To identify shifts in gender-specific polypharmacy patterns over time.

Main Methods:

• A repeated cross-sectional study design was employed.
• Analysis of dispensing records from a 10% nationally representative sample of Australian Pharmaceutical Benefits Scheme (PBS) beneficiaries.
• Polypharmacy defined as ≥5 regular medicines and hyperpolypharmacy as ≥10 regular medicines.

Main Results:

• Polypharmacy prevalence increased from 8.0% in 2013 to 9.2% in 2024, affecting two million Australians.
• While initially higher in women, men surpassed women in prevalence from middle age onward by 2024.
• Men showed increasing average annual percentage change (AAPC) across adult and older adult groups, with notable growth in middle, early older, and later older age strata.

Conclusions:

• Shifting gender trends in polypharmacy are evident, with stabilizing or declining prevalence in women and sustained growth in men.
• The findings suggest a changing prescribing landscape necessitating gender-stratified monitoring and targeted interventions.
• Further research is needed to understand the long-term consequences of increasing polypharmacy in younger and middle-aged adults.