Factors associated with polypharmacy and the high risk of medication-related problems among older community-dwelling adults in European countries: a longitudinal study.

BACKGROUND: Polypharmacy can be defined as using five or more medications simultaneously. "Medication-related problems", an extension of polypharmacy, includes inappropriate prescribing, poor adherence, overdosage, underdosage, inappropriate drug selection, inadequate monitoring, adverse drug effects, and drug interactions. Polypharmacy and the high risk of medication-related problems among older people are associated with adverse health consequences due to drug-drug interactions, drug-disease interactions, and adverse drug effects. This study aims to assess the factors associated with polypharmacy and the high risk of medication-related problems among community-dwelling older people in the Netherlands, Greece, Croatia, Spain, United Kingdom. METHOD: This longitudinal study used baseline and follow-up data from 1791 participants of the Urban Health Center European project. Polypharmacy and the risk of medication-related problems were evaluated at baseline and follow-up using the Medication Risk Questionnaire. We studied factors in the domains (a) sociodemographic characteristics, (b) lifestyle and nutrition, and (c) health and health care use. Hierarchical logistic regression analyses were used to examine the factors associated with polypharmacy and the high risk of medication-related problems. RESULTS: Mean age was 79.6 years (SD ± 5.6 years); 60.8% were women; 45.2% had polypharmacy, and 41.8% had a high risk of medication-related problems. Women participants had lower odds of polypharmacy (OR = 0.55;95%CI:0.42-0.72) and a high risk of medication-related problems (OR = 0.50; 95%CI:0.39-0.65). Participants with a migration background (OR = 1.67;95%CI:1.08-2.59), overweight (OR = 1.37; 95%CI:1.04-1.79) and obesity (OR = 1.78;95%CI:1.26-2.51) compared to 'normal weight', with lower physical HRQoL (OR = 0.96, 95%CI:0.95-0.98), multi-morbidity (OR = 3.73, 95%CI:2.18-6.37), frailty (OR = 1.69, 95%CI:1.24-2.30), visited outpatient services (OR = 1.77, 95%CI: 1.09-2.88) had higher odds of polypharmacy. The associations with the high risk of medication-related problems were similar. CONCLUSIONS: Multiple factors in demography, lifestyle, nutrition, and health care use are associated with polypharmacy and the high risk of medication-related problems. Polypharmacy is a single element that may reflect the number of medications taken. The broader content of medication-related problems should be considered to assess the context of medication use among older people comprehensively. These provide starting points to improve interventions to reduce polypharmacy and high risk of medication-related problems. In the meantime, health professionals can apply these insights to identify subgroups of patients at a high risk of polypharmacy and medication-related problems. TRIAL REGISTRATION: The intervention of the UHCE project was registered in the ISRCTN registry as ISRCTN52788952. The date of registration is 13/03/2017.

The association between frailty and the risk of medication-related problems among community-dwelling older adults in Europe.

BACKGROUND: Studies revealed unidirectional associations between frailty and medication-related problems (MRPs) among older adults. Less is known about the association between frailty and the risk of MRPs. We aimed to assess the bi-directional association between frailty and the risk of MRPs in community-dwelling older adults in five European countries. METHODS: Participants were 1785 older adults in the population-based Urban Health Centres Europe project. Repeated assessments were collected at baseline and one-year follow-up, including frailty, the risk of MRPs, and covariates. Linear regression analyses were conducted to examine the unidirectional associations. A cross-lagged panel modeling was used to assess bi-directional associations. RESULTS: The unidirectional association between frailty at baseline and the risk of MRPs at follow-up remained statistically significant after adjusting for covariates (ß = 0.10, 95%CI:0.08, 0.13). The association between the risk of MRPs at baseline and frailty at follow-up shows similar trends. The bi-directional association was comparable with reported unidirectional associations, with a stronger effect from frailty at baseline to the risk of MRPs at follow-up than reversed path (Wald test for comparing lagged effects: p < 0.05). CONCLUSION: This longitudinal study suggests that a cycle may exist where older adults with higher frailty levels are more likely to have a higher risk of MRPs, which in turn contributes to developing a higher level of frailty. Further research is needed to validate our findings and explore underlying pathways.