Assessing the impact of cognitive impairment on the usability of an electronic medication delivery unit in an assisted living population

摘要

Purpose: To examine the relationship between cognitive status and the usability of an integrated medication delivery unit (MDU) in older adults who reside in an Assisted Living Facility (ALF). Methods: Subjects were recruited from a single ALF in Pittsburgh, PA. Usability testing sessions required subjects to execute tasks essential to using EMMA~® (Electronic Medication Management Assistant), a Class Ⅱ Federal Drug Administration (FDA) approved integrated MDU. Video coding allowed for quantification of usability errors observed during the testing sessions. Each subject's cognitive status was assessed using the Mini Mental State Exam (MMSE~®) with scores ＜24 indicating cognitive impairment. Functional status was assessed using the Lawton Instrumental Activities of Daily Living (IADL) questionnaire, and a global assessment of subjective usability was assessed by completing the System Usability Scale (SUS). Non-parametric statistics and correlation analysis were used to determine whether significant differences existed between cognitively impaired and non-impaired subjects. Results: Nineteen subjects were recruited and completed the protocol. The subject pool was primarily white, female, 80+ and in possession of above average education. There was a significant relationship between MMSE~® scores and the percentage of task success (z = -2.03, p = 0.04). Subjects with MMSE~® scores of 24+ (no cognitive impairment) successfully completed an average of 69.0% of tasks vs. the 34.7% performance for those in the cognitively impaired group (＜24). Six of the unimpaired group also succeeded at meeting the 85% (6 out of 7 correct) threshold. No subject with cognitive impairments (＜24 MMSE~®) completed more than 5/7 (71.4%) of their tasks. Two of the impaired subjects failed all of the tasks. Three of the MMSE~®'s subsections (Date, Location and Spell 'world' backwards) were found to be significantly related (p ＜ 0.05) to the percentage of task success. Tasks success rates were related with IADL scores (z = -3.826, p ＜ 0.0001), and SUS scores (r = 0.467, p = 0.0429). Conclusions: Medication delivery units like EMMA~® have the potential to improve medication management by combining reminder systems with telemedical monitoring and control capabilities. However, subjects judged to be "cognitively impaired" (＜24 MMSE~®) scored a significantly smaller percentage of task success than the "unimpaired" (＞ = 24), suggesting that cognitive screening of patients prior to the use of EMMA~® may be advisable. Further studies are needed to test the use of EMMA~® amongst ALF residents without cognitive impairment to see if this technology can improve medication adherence.