Potentially inappropriate medications in community-dwelling older adults undertaken as a comprehensive geriatric risk assessment

The prescription of potentially inappropriate medications (PIMs) is associated with an increase in adverse events, prescribing cascades, high health-care costs, morbidity, and mortality in the elderly. The overarching objective of this study is to examine the prevalence of PIMs in the elderly, applying the 2012 American Geriatrics Society Beers criteria for the study period 2012–2014, and the updated 2015 Beers criteria for 2015. The study population (N = 70,479) included a continuously recruited national cohort of community-dwelling older (aged ≥ 65 years) New Zealanders who had undertaken the International Resident Assessment Instrument-Home Care (interRAI-HC) assessments between September 2012 and October 2015. Exposure of PIMs 90 days before and after assessment, and 90–180 days after assessment are reported. Exposure to PIMs was highest in individuals aged over 95 years and in males. The average number of PIMs prescribed 90 days before assessment during the period 2015 was marginally higher compared to 2012–2014 (0.19 versus 0.04), and a greater number of individuals were exposed to one or more PIMs in 2015 compared to 2012–2014 (7.13 versus 2.17%). The prevalence of PIMs 90 days before and after assessment was 2.17 and 6.92% for 2012–2014, and 7.13 and 24.7% for 2015, respectively. The percent change in PIMs in 2012–2014 and 2015 after 90 days of assessment were 4.70% (confidence interval (CI) 4.50%, 5.00%, p