Does polypharmacy shape dependency transitions in the very old? Findings from the Newcastle 85+ Study

Abstract

Background: helping older people to maintain their independence, and identifying risk factors that compromise this, is of high importance. Polypharmacy is common in the very old (aged ≥ 85) but whether it can shape transitions in dependency in this fastest growing subpopulation is unclear.

Methods: using Newcastle 85+ Study data and multi-state modelling, we investigated the association between each additional medication prescribed and the progression of and recovery from dependency states, over 10 years (age 85-95). Participants were defined as either free from care (independent), requiring care less often than daily (low dependency), or requiring care at regular intervals each day or 24 hourly (medium/high dependency).

Results: each additional medication prescribed was associated with a 10% decreased chance of recovery from low dependence to independence (hazard ratio (HR): 0.90, 95% confidence interval (CI): 0.82-0.99).

Discussion: when a relatively able person visits the GP or clinical pharmacist, careful consideration should be given to whether the potential benefits from adding a new medication outweigh the risk to reduced recovery of independence.

Keywords: older people; polypharmacy; primary care; very old.

Figure 1

Prevalence of dependency from 85 to 95 years of age.