Classifying Polypharmacy According to Pharmacotherapeutic and Clinical Risks in Older Adults: A Latent Class Analysis in Quebec, Canada

INTRODUCTION

The simplistic definition of polypharmacy, often designated as the concomitant use of five medications or more, does not distinguish appropriate from inappropriate polypharmacy. Classifying polypharmacy according to varying levels of health risk would help optimise medication use.

OBJECTIVE

We aimed to characterise different types of polypharmacy among older adults and evaluate their association with mortality and institutionalisation.

METHODS

Using healthcare databases from the Quebec Integrated Chronic Disease Surveillance System, we selected a community-based random sample of the population ≥ 66 years old covered by the public drug plan. Categorical indicators used to describe polypharmacy included number of medications, potentially inappropriate medications (PIMs), drug-drug interactions, enhanced surveillance medications, complex route of administration medications, anticholinergic cognitive burden (ACB) score and use of blister cards. We used a latent class analysis to subdivide participants into distinct groups of polypharmacy. Their association with 3-year mortality and institutionalisation was assessed with adjusted Cox models.

RESULTS

In total, 93,516 individuals were included. A four-class model was selected with groups described as (1) no polypharmacy (46% of our sample), (2) high-medium number of medications, low risk (33%), (3) medium number of medications, PIM use with or without high ACB score (8%) and (4) hyperpolypharmacy, complex use, high risk (13%). Using the class without polypharmacy as the reference, all polypharmacy classes were associated with 3-year mortality and institutionalisation, with the most complex/inappropriate classes denoting the highest risk (hazard ratio [HR] [95% confidence interval]: class 3, 70-year-old point estimate for mortality 1.52 [1.30-1.78] and institutionalisation 1.86 [1.52-2.29]; class 4, 70-year-old point estimate for mortality 2.74 [2.44-3.08] and institutionalisation 3.11 [2.60-3.70]).

CONCLUSIONS

We distinguished three types of polypharmacy with varying pharmacotherapeutic and clinical appropriateness. Our results highlight the value of looking beyond the number of medications to assess polypharmacy.

[Relation between grip strength of independent elders and functional decline following an emergency department visit : a pan-Canadian study]

OBJECTIVE

To determine whether grip strength and fear of falling are associated with functional decline at 3 or 6 months after a minor trauma assessed in the emergency department.

METHOD

Prospective multicenter cohort study of patient's aged 65 years and older, independent for activities of daily living, consulting the emergency department for minor trauma. Functional status, fear of falling, and grip strength measurements were collected. Functional decline was measured at 3 and 6 months.

STATISTICS

Two groups were compared : one with functional decline, the other without. A ROC curve explored the predictive power of grip strength and initial fear of falling on the occurrence of functional decline.

RESULTS

Participants were 74.7 years old, 52 % men. Initial peak grip strengths were identical (p superior to 0.05). Grip strength and fear of falling were not predictive of functional decline (p = 0.55 and p = 0.53). However, fear of falling was associated with functional decline (OR: 1.141 95 % CI [1.032-1.261]; p = 0.009).

CONCLUSION

In the autonomous elder with minor trauma in the emergency department, grip strength is not associated with subsequent functional decline. But fear of falling is associated with decline at 6 months.