Abstract
BACKGROUND: The Medication-Related Burden Quality of Life (MRB-QoL) tool has been developed to measure the burden of medications on functioning and wellbeing from a patient perspective. However, predictors of MRB-QoL were not reported in greater detail in the validation study. This study aimed to explore factors associated with MRB-QoL to see whether there is any new information that calls for further research. METHODS: Analysis of data from the MRB-QoL validation study was undertaken. Outcome variables were domains of the MRB-QoL (Routine and Regimen Complexity, Psychological Burden, Functional and Role Limitation, Therapeutic Relationship, and Social Burden). Explanatory variables were patient age; disease-related factors; and medication-related factors, such as number of medications, complexity of medication regimen (measured by the Medication Regimen Complexity Index [MRCI]), and exposure to medications with anticholinergic and sedative effects (measured by the Drug Burden Index [DBI]). Linear regression analyses were used to identify factors associated with the MRB-QoL. RESULTS: The study included 367 participants (52.1% male), with a median age of 64 years. In multivariable regression analyses, an increase in the DBI was significantly associated with poorer Psychological wellbeing (β=-0.15, p<0.001) and Functional and Role Limitation (β=-1.79, p<0.001). Living with three or more medical conditions was significantly associated with poorer Psychological wellbeing (β=-0.21, p<0.001). Age was significantly associated with all domains of the MRB-QoL (β=0.28 to 0.55). Polypharmacy and MRCI were not associated with any of the MRB-QoL domains. CONCLUSION: In this sample of community-dwelling adults with multiple medications, the DBI was independently associated with the Psychological Burden and Functional and Role Limitation domains of the MRB-QoL. This study provides preliminary evidence on factors affecting medication-related quality of life outcomes from a patient perspective. Future longitudinal studies, along with further psychometric testing of the MRB-QoL measure, are warranted to better understand predictors of MRB-QoL.