Functional Decline Associated with Polypharmacy and Potentially Inappropriate Medications in Community-Dwelling Older Adults with Dementia

This study provides empirical evidence on whether polypharmacy and potentially inappropriate prescription medications (PIRx, as defined by the 2003 Beers criteria) increase the likelihood of functional decline among community-dwelling older adults with dementia. Data were from the National Alzheimer's Coordinating Center, Uniform Data Set (9/2005-9/2009). Study sample included 1,994 community-dwelling subjects aged ≥65 with dementia at baseline. Results showed that subjects having ≥5 medications were more likely to have functional decline than subjects having <5 medications. However, the increased likelihood was only apparent in subjects who did not have PIRx. Instead of magnifying the associated risk as hypothesized, PIRx appeared to have a protective effect albeit marginally statistically significant. Therefore, increased medication burden may be associated with functional decline in community-dwelling older adults with dementia who are not prescribed with PIRx. More research is needed to understand which classes of medications have the most deleterious effect on this population.