PhD student Research Department of Primary Care and Population Health, University College London London, United Kingdom
Background: Polypharmacy (concurrent use of multiple medications) increases the risk of inappropriate and unsafe prescribing. With a rapidly ageing population, polypharmacy is a global public health issue. Few studies have documented its prevalence in different socio-demographic groups.
Objectives: To estimate the prevalence of polypharmacy and hyper-polypharmacy in general population in the UK over 20 years, by socio-demographic characteristics.
Methods: We included participants aged 18 years+ contributing to a primary care database (the IQVIA Medical Research Data) from 1999 to 2018. Polypharmacy was defined as the concurrent use of ≥5 drugs classes and hyper-polypharmacy ≥10 drugs classes. We determined the number of drug classes prescribed for more than 90 days consecutively and performed Poisson regression analysis to estimate the prevalence each year adjusted age, sex, and social deprivation.
Results: We included 56,982,559 person-years from 1999 to 2018. For the all age-groups of participants, the crude prevalence of polypharmacy and hyper-polypharmacy were 3.6% and 0.3% in the first 5 years of the study period (1999–2003) and then increased year by year to about 11.6% and 1.9% in the last 5 years (2014–2018). The adjusted prevalence of polypharmacy in 60-64 and 80-84 age-groups were 5.6% and 12.2% in the first 5 years (1999–2003); then, increased drastically to 17.8% and 46.5% in the last 5 years (2014–2018). In the adjusted prevalence of hyper-polypharmacy, the similar trend was observed, with 0.5% of those in 60-64 age-group and 1.0% of those in 80-84 age-group in the first 5 years (1999–2003), increasing to 3.0% and 8.0% respectively in the last 5 years (2014–2018). Also, we found a slightly greater prevalence of polypharmacy in males than in females, and a greater prevalence in those who lived in the most deprived areas compared to the least deprived.
Conclusions: Polypharmacy and hyper-polypharmacy increased substantially over 20 years. This data supports initiatives to promote de-prescribing in older people with polypharmacy.
