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Caregiver appraisals of lucid episodes in people with late‐stage Alzheimer's disease or related dementias

Abstract Introduction Little is known about how family caregivers who witness unexpected and spontaneous communication among people in late stages of Alzheimer's disease and related dementias (ADRD) appraise these episodes of lucidity (EL). Methods In an electronic, cross‐sectional survey for former and current caregivers who participate in UsAgainstAlzheimer's A‐LIST®, participants who reported witnessing an EL were asked how positive and stressful ELs were, if they made or changed decisions based on an EL, and what resources they sought out to explain ELs. Results Caregivers reported 72% of ELs to be quite a bit or very positive, 17% to be stressful, and 10% to be both stressful and positive. Twelve percent of caregivers changed care plans because of ELs and 13% sought out information about ELs. Discussion These exploratory data suggest caregiver reactions to EL vary. Caregivers may change or postpone care decisions due to EL, and few resources exist to address caregiver queries about EL.

knowledge of available services, and preparation for future care needs for relatives. 6,7 1. Systematic Review: The authors reviewed literature using traditional (e.g., PubMed) sources. Research on episodes of lucidity (EL) is in the earliest stages. To date, most research has relied on case reports and cross-sectional study designs. Recent publications describe scientific and methodological challenges in studying EL.
These relevant citations are appropriately cited.
2. Interpretation: Findings suggest that caregiver reactions and appraisals to EL vary, and experiencing EL may affect care decisions that caregivers make on behalf of those with late-stage Alzheimer's disease and related dementia (ADRD). Caregivers seek out information, but few evidence-based resources exist to guide caregivers through these experiences. Especially difficult transitions for caregivers occur during the grief and readjustment stage, particularly in late-stage ADRD when their relatives' communication is limited and coherent capacity is assumed to be lost. 8,9 During this stage, caregivers must cope with the inevitability of their relatives' irreversible cognitive and physical function loss while making decisions about care needs and end-of-life plans. It is possible, therefore, that unexpected and spontaneous episodes of lucidity (EL) among people with late-stage ADRD, as have been reported in case studies, [10][11][12] can also disrupt the caregiver's transition and ability to prepare for change. These lucid episodes, also referred to as paradoxical lucidity, are characterized by spontaneous mental clarity with verbal or non-verbal communication or behavior among people who had previously been thought to lack the cognitive capacity to do so. 13,14 There is growing interest in the neuropathology of EL and the clinical implications of whether they indicate disease progression, 14 but how, when, or why these episodes occur is not well understood, and clear scientific definitions of EL are still lacking. [15][16][17] Even less is known about how caregivers who witness these episodes appraise and react to them, if they consider them beneficial or stressful, or if they prompt changes in how they manage or make decisions about care for their care recipients. To assess caregiver appraisals of EL and what, if any, information they sought out as a result of this experience or to prepare them for EL, we analyzed cross-sectional data from former/current caregivers of people living with ADRD who reported witnessing an EL. This study, one of six funded by National Institute on Aging to advance scientific understanding of lucidity in dementia, 13 is part of a larger parent study to develop typologies of EL experiences by characterizing their frequency, duration, mode (e.g., verbal, non-verbal), content of communication, and triggering circumstances. In the parent study, survey data are used to develop preliminary typologies, and then, using qualitative data from in-depth interviews, the typologies are refined. 18,19 The validity of the refined typologies will then be tested in a subsequent longitudinal study with current caregiverswhich will help further characterize EL, establish prevalence estimates, and evaluate how different EL types are associated with caregiver reactions. Given the paucity of data on ELs, findings presented in this ancillary study will inform which questions are used to assess the effect caregiver appraisals of EL have on caregiver strain, quality of life, and bereavement responses in the longitudinal study.

Sample
Participants were recruited from UsAgainstAlzheimer's, an advocacy group that aims to mobilize participation in research on effective treatments and care quality for ADRD (usagainstalzheimers.org). UsAgain-stAlzheimer's administers the A-LIST ® , a unique online community of 10,000 individuals who self-identify either as someone at risk for or with mild cognitive impairment (MCI) or ADRD, a current or former caregiver for someone with ADRD, or someone interested in brain health (alist4research.org). Included in this analysis are current or former caregivers of someone with ADRD who enrolled in the A-LIST and reported witnessing an EL. The UsAgainstAlzheimer's Institutional Review Board approved the study and all participants provided informed consent prior to participating.

Procedures
In February 2021, UsAgainstAlzheimer's sent an e-mail to A-LIST participants who had previously identified as current or former caregivers or had never identified their role, but had previously responded to A-LIST correspondence (n = 3569). Invitations requested participation from current and former caregivers of someone with ADRD, described EL and the study's purpose, and provided a hyperlink to an electronic survey. Non-responders were e-mailed reminders 4 and 15 days after the original mailing.
The survey included a general description of an EL: "A lucid experience is an unexpected, spontaneous, meaningful, and relevant communication with your relative, friend or neighbor when they had lost the ability to speak or have personal interactions." Respondents were asked if they had ever witnessed an EL in a relative, friend, or neighbor who has ADRD and were given the option to report up to two episodes.
Of 538 respondents who responded (out of 3569), 58 were not cur-

Measures
Data included demographic information about the caregiver, care recipient, their relationship, and descriptive information about the witnessed EL(s). Questions on EL were informed by Batthyány and Greyson. 10 Respondents were asked about: (1) their appraisal of the EL (i.e., how positive and stressful it was; rated from 1 = not at all to 5 = very),     Table S1 in supporting information).

RESULTS
Positive appraisals did not show significant associations with any caregiver demographics.
Overall, 12% of caregivers made changes based on ELs-most commonly modifications to a care recipient's living arrangements, social needs, and medical care, and less frequently on personal needs, strategies to improve care, finances, and end of life planning. Thirteen percent sought out information or educational materials about ELs, mainly from a health-care provider or the internet. More than 50% desired information on why ELs occur, >40% on how to recreate them, and >37% on how best to respond to ELs.

DISCUSSION
In our study, we found that the majority of caregivers who witnessed ELs consider them to be positive. Among caregivers of people with ADRD, positive appraisals of caregiving may help buffer stress, 20,21 and therefore, it is possible that a positively appraised EL helps safeguard caregivers from stress. Conversely, it is also possible that caregivers who appraise EL as stressful may experience greater stress during TA B L E 1 Self-reported characteristics of caregiver participants and their proxy report of characteristics of care recipients who had an episode of lucidity a
A small but potentially meaningful percentage of caregivers in this study sought out EL information from health-care providers or the internet, suggesting a need for reliable information. As additional data from the parent study emerges on types of EL and its consequences, we will be able to develop reliable educational resources for broad dissemination in partnership with advocacy organizations.
Last, some caregivers in this study made changes to how they manage care after witnessing an EL. Our larger parent study includes a longitudinal study to assess the frequency and outcomes of these planning decisions, including their beneficial or detrimental effects on caregiver and care recipient outcomes, which, in turn, can be used to develop future caregiver interventions, psychoeducation, and epidemiological research on EL. As additional research emerges on EL, health-care providers will also need to be prepared to address questions about EL.
They will need to consider caregiver experiences with EL when devel-oping care plans and provide guidance on caregiver decision making after experiencing EL. 22  Finally, our sample was predominately White (85%) and findings may not be generalizable. More diverse representation in future research is critical for understanding variation in caregiver reactions to EL. The forthcoming parent study will address these limitations.

CONCLUSIONS
Findings suggest that caregiver appraisals of EL are generally positive but also considered stressful among some. Witnessing ELs prompts some caregivers to change or postpone care decisions related to their relative with late-stage ADRD. Few evidence-based resources exist to guide caregivers through these experiences. Future research is needed to build knowledge in this understudied aspect of ADRD and to understand its effect on caregivers.

ACKNOWLEDGMENTS
The authors wish to acknowledge the participants who gave their time and shared their experiences for this research and the Kern Center for the Science of Healthcare Delivery at Mayo Clinic. This study was supported by funding from National Institute on Aging, Grant #5R21AG069767-02.

CONFLICTS OF INTEREST
Dr. Griffin discloses a contract with Exact Sciences Corp. that is paid to her institution. No other authors report conflicts of interest.