Premium
Long‐term trajectories of medicine use among older adults experiencing polypharmacy in Australia
Author(s) -
Falster Michael O.,
Charrier Rayan,
Pearson SallieAnne,
Buckley Nicholas A.,
Daniels Benjamin
Publication year - 2021
Publication title -
british journal of clinical pharmacology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.216
H-Index - 146
eISSN - 1365-2125
pISSN - 0306-5251
DOI - 10.1111/bcp.14504
Subject(s) - polypharmacy , medicine , older people , cohort , pharmaceutical benefits scheme , demography , population , geriatrics , gerontology , medical prescription , environmental health , psychiatry , pharmacology , sociology
Aims To explore longitudinal changes in the number and type of medicines used among older people who experience polypharmacy. Methods We used pharmaceutical claims for a 10% sample of Australian Pharmaceutical Benefits Scheme beneficiaries to identify people aged 70 years and older who were exposed to 5 or more medicines on 15 February 2014. Using group‐based trajectory modelling, we explored changes in the quarterly number and type of medicines used over a 5‐year period (2014–2018). Results In our cohort of 98 539 people, we identified 2 predominant groups of medicine use: sustained polypharmacy (77% of people, 4 trajectories); and decreasing medicine use (23%, 3 trajectories). Within the sustained polypharmacy group, people in trajectories with a lower mean number of medicines (e.g. 6 unique medicines) had relatively stable trajectories, while those using a higher number of medicines (e.g. 15 unique medicines) experienced greater seasonal variation in the number and type of medicines used. On average, people continued to use 2/3 of their medicines (chemical substance level) across adjacent quarters. Within groups of decreasing medicine use, the most common trajectory was a slight drop in medicines within 3 months. Overall, 79% of people still experienced polypharmacy after 1 year. Conclusion Polypharmacy among older people is a sustained phenomenon, reflecting the chronic nature of multimorbidity within this population. However, there is an underlying volatility in the nature of medicines involved, reflecting both changes in treatment and seasonal fluctuation in dispensing. Ongoing prescribing vigilance is required, particularly for patients using very large amounts of medicines.