Multifaceted Prospective Memory Intervention to Improve Medication Adherence

Abstract

Objectives: To test whether a multifaceted prospective memory intervention improved adherence to antihypertensive medications and to assess whether executive function and working memory processes moderated the intervention effects.

Design: Two-group longitudinal randomized control trial.

Setting: Community.

Participants: Individuals aged 65 and older without signs of dementia or symptoms of severe depression who were self-managing prescribed medication.

Measurements: After 4 weeks of initial adherence monitoring using a medication event monitoring system, individuals with 90% or less adherence were randomly assigned to groups.

Intervention: The prospective memory intervention was designed to provide strategies that switch older adults from relying on executive function and working memory processes (that show effects of cognitive aging) to mostly automatic associative processes (that are relatively spared with normal aging) for remembering to take medications. Strategies included establishing a routine, establishing cues strongly associated with medication taking actions, performing the action immediately upon thinking about it, using a medication organizer, and imagining medication taking to enhance encoding and improve cuing.

Results: There was significant improvement in adherence in the intervention group (57% at baseline to 78% after the intervention), but most of these gains were lost after 5 months. The control condition started at 68% and was stable during the intervention, but dropped to 62%. Executive function and working memory moderated the intervention effect, with the intervention producing greater benefit for those with lower executive function and working memory.

Conclusion: The intervention improved adherence, but the benefits were not sustained. Further research is needed to determine how to sustain the substantial initial benefits.

Keywords: elderly; hypertension; intervention; medication adherence; prospective memory.