Polypharmacy and frailty: prevalence, relationship, and impact on mortality in a French sample of 2350 old people

M. Herr, J.M. Robine, J. Pinot, J.J. Arvieu, J. Ankri

Pharmacoepidemiology and drug safety. 2015;24(6):637-46

Frail older people often have multiple chronic conditions and may therefore be particularly at risk of polypharmacy. Ageing-related changes in body composition (sarcopenia) and organ function (decrease in renal and metabolic clearance) can be exacerbated in frail people, making them more vulnerable to drug-related problems.

This cross-sectional population study aimed to assess the prevalence of polypharmacy and frailty, to examine their association, and to establish their independent and combined effects on mortality in a sample of 2350 French older people aged 70 years and over.

Participants were interviewed at home in 2008-2010. Frailty was defined as impairment in three domains or more among nutrition, energy, physical activity, strength, and mobility, in the absence of difficulties in basic activities of daily living. Mortality data were documented after a mean follow-up period of 2.6 years.

The frailty prevalence was 17.0%. Polypharmacy (5–9 drugs) was reported in 53.6% of the population, and excessive polypharmacy (10 drugs or more) in 13.8%. After adjustment for socio-demographic and health variables, polypharmacy and excessive polypharmacy were associated with frailty (odds ratio 1.77 [1.20–2.61] and 4.47 [2.37–8.42] respectively). Frailty (hazard ratio [HR] 2.56 [1.63–4.04]) and excessive polypharmacy (HR 1.83[1.28–2.62]) were independent predictors of mortality. Compared with non-frail people without polypharmacy, frail people with excessive polypharmacy were six times more likely to die during the follow-up period (HR 6.30 [3.09–12.84]).

Comment: This study confirmed that frailty and polypharmacy are common in the older population, polypharmacy and frailty are strongly related to each other, and both are predictive of mortality. Understanding better the relationship between polypharmacy and frailty and their consequences in old people is a key challenge from both a clinical and a public health perspective, because it may identify a population likely to take advantage of preventive actions.