Structural equation modeling to predict medication adherence in older people assisted by the public health system
DOI:
https://doi.org/10.1590/s2175-97902026e24427Keywords:
Psychotropic drugs, Medication adherence, Health of the elderly, Public health, Use of medicationsAbstract
With the increase in life expectancy, the demand for pharmaceutical care has risen, with the need to improve drug adherence. The study aimed to evaluate which variables in the literature most influence adherence. Two hundred twenty older patients from a specialty outpatient clinic were included. Potential drug interactions were identified using the Brief Medication Questionnaire (BMQ), and the Cumulative Illness Ratings Scales for Geriatrics and WHOQOL-Bref questionnaires were applied. The mean follow-up time at the outpatient clinic was 7.7 years, with 65% belonging to socioeconomic class C. The mean number of medications in use was 7, and 44% of the participants were taking psychotropic medication; 80.5% showed potential drug interaction. Cluster analysis revealed two groups: those motivated but concerned about their pharmacotherapy, and another with higher scores in drug effects and bothersome features, pain, and fear related to pharmacotherapy. The structural equation model showed that the BMQ total score was dependent on drug interaction and the public healthcare system's supply of medications. The concurrent use of multiple drugs and potential drug interaction favor non-adherence to medication, while adherence increases when the drug is provided by the health system, aspects that should be observed by the pharmaceutical attention to improve the treatment of older people.
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