Original ArticlesSubtle Changes in Medication-taking Are Associated With Incident Mild Cognitive ImpairmentDorociak, Katherine E. PhD*; Mattek, Nora MPH†,‡; Ferguson, John E. PhD§,∥; Beattie, Zachary T. PhD†,‡; Sharma, Nicole BA†,‡; Kaye, Jeffrey A. PhD†,‡; Leese, Mira I. BA§; Doane, Bridget M. PhD§; Hughes, Adriana M. PhD†,‡,§,¶Author Information *Palo Alto VA Health Care System, Palo Alto, CA †Department of Neurology, Oregon Health & Science University ‡Oregon Center for Aging & Technology, Portland, OR §Minneapolis VA Health Care System Departments of ∥Rehabilitation Medicine ¶Psychiatry, University of Minnesota, Minneapolis, MN Supported in part by funding from the National Institutes of Health grants P30AG024978 and P30AG008017 and by the Minneapolis VA Health Care System. The contents do not represent the views of the US Department of Veteran Affairs or the US Government. The authors declare no conflicts of interest. Reprints: Katherine E. Dorociak, PhD, Palo Alto VA Health Care System, Palo Alto, CA 94304 (e-mail: [email protected]). Alzheimer Disease & Associated Disorders: July-September 2021 - Volume 35 - Issue 3 - p 237-243 doi: 10.1097/WAD.0000000000000439 Buy Metrics Abstract Introduction: Medication-taking is a routine instrumental activity of daily living affected by mild cognitive impairment (MCI) but difficult to measure with clinical tools. This prospective longitudinal study examined in-home medication-taking and transition from normative aging to MCI. Methods: Daily, weekly, and monthly medication-taking metrics derived from an instrumented pillbox were examined in 64 healthy cognitively intact older adults (Mage=85.5 y) followed for a mean of 2.3 years; 9 transitioned to MCI during study follow-up. Results: In the time up to and after MCI diagnosis, incident MCI participants opened their pillbox later in the day (by 19 min/mo; β=0.46, P<0.001) and had increased day-to-day variability in the first pillbox opening over time (by 4 min/mo) as compared with stable cognitively intact participants (β=4.0, P=0.003). Discussion: Individuals who transitioned to MCI opened their pillboxes later in the day and were more variable in their medication-taking habits. These differences increased in the time up to and after diagnosis of MCI. Unobtrusive medication-taking monitoring is an ecologically valid approach for identifying early activity of daily living changes that signal transition to MCI. Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.