A multi-centre cohort study on healthcare use due to medication-related harm: the role of frailty and polypharmacy

Objectives To determine the association between frailty and medication-related harm requiring healthcare utilisation. Design Prospective observational cohort study. Setting Six primary and five secondary care sites across South East England, September 2013-November 2015. Participants One thousand and two hundred and eighty participants, >= 65 years old, who were due for discharge from general medicine and older persons' wards following an acute episode of care. Exclusion criteria were limited life expectancy, transfer to another hospital and consent not gained. Main outcome measures Medication-related harm requiring healthcare utilisation (including primary, secondary or tertiary care consultations related to MRH), including adverse drug reactions, non-adherence and medication error determined via the review of data from three sources: patient/carer reports gathered through a structured telephone interview; primary care medical record review; and prospective consultant-led review of readmission to recruiting hospital. Frailty was measured using a Frailty Index, developed using a standardised approach. Marginal estimates were obtained from logistic regression models to examine how probabilities of healthcare service use due to medication-related harm were associated with increasing number of medicines and frailty. Results Healthcare utilisation due to medication-related harm was significantly associated with frailty (OR = 10.06, 95% CI 2.06-49.26, P = 0.004), independent of age, gender, and number of medicines. With increasing frailty, the need for healthcare use as a result of MRH increases from a probability of around 0.2-0.4. This is also the case for the number of medicines. Conclusions Frailty is associated with MRH, independent of polypharmacy. Reducing the burden of frailty through an integrated health and social care approach, alongside strategies to reduce inappropriate polypharmacy, may reduce MRH related healthcare utilisation.