Inadequate knowledge of prescription drugs and their predictors in very old patients and their caregivers

Abstract Objective Identify predictors of inadequate knowledge about the medication prescribed to very old outpatients and their caregivers. Method The knowledge on the medication prescribed for 80 patients aged 80 years and over was assessed using a validated questionnaire to interview patients or their caregivers (when patients had communication difficulties, dementia, or any need for care to help them take the medication). Two hierarchical logistic regression models assessed the association between inadequate knowledge of the medication and sociodemographic and drug variables. Results Thirty-nine (48.8%) respondents were caregivers. Inadequate knowledge was found in 81.5% (404/496) of medication prescribed. Route of Administration, Dose, Frequency, and Duration of Treatment were the aspects of greatest knowledge, whereas Adverse Effects, Precautions, Interactions, and Contraindications were the least known ones. In the first model, inadequate knowledge was associated to the level of education from complete elementary school to incomplete high school (Odds Ratio (OR): 0.12; p=0.018), from high school to incomplete higher education (OR: 0.12; p