Regimen complexity and medication nonadherence in elderly patients

OBJECTIVE To assess whether the number of daily administrations of individual drugs, as a measure of regimen complexity, contributes to the profile of an elderly patient who adheres poorly to the prescribed therapy. POPULATION Six hundred ninety patients over 64 years who were consecutively admitted to 11 acute medical care and three long term/rehabilitation wards in Italy. MAIN OUTCOME MEASURE Self-reported adherence to drugs taken at home before admission was measured by a single question assessment for each listed drug supplemented with a latter question about the circumstances of the missed administration. For cognitively impaired patients the question was put to patients' relatives or caregivers. METHODS A structured multidimensional assessment was performed to identify nonadherence and its potential correlates. Correlates of nonadherence were identified by multivariable logistic regression. RESULTS We recorded 44 cases (6.4%) of nonadherence to at least one drug. Being assisted by foreign caregivers (OR 2.17; 95% CI 1.02-4.63) and the use of at least one multiple daily dosing drug (OR 2.99; 95% CI 1.24-7.17) were significant independent correlates of medication nonadherence, while age, selected indexes of frailty and the cumulative number of prescribed drugs were not. CONCLUSION Regimen complexity and type of assistance are independent correlates of medication nonadherence.