Toward harmonization of strategies for investigating lucidity in AD/ADRD: A preliminary research framework

Abstract

Episodes of lucidity (ELs) in Alzheimer's disease and Alzheimer's disease-related dementias (AD/ADRD), have garnered increasing attention as an important area of research. Efforts to study lucidity suffer from a lack of clear definitional criteria, inconsistent conceptualization, and diverse approaches to operationalizing features of these events. To advance systematic investigation of ELs in AD/ADRD, there is a need for clarity and precision in labeling event attributes, markers, and specific measurement strategies that enable operational harmonization across distinct approaches to investigating the relatively broad and nascent phenomenon. To that end, we propose a preliminary research framework to guide harmonization of approaches to investigating ELs in AD/ADRD. Our goal is to provide an initial schematic that encourages uniform labeling of operational decisions about ELs.

The Impact of Episodes of Lucidity on People Living With Dementia and Their Caregivers

“…The lack of a clear definition for ELs raises important methodological considerations as broader definitional boundaries may make it increasingly challenging to disambiguate ELs from cognitive fluctuation, yet a narrow and specific definition for ELs risks excluding related experiences at this preliminary stage in research. 5 It is clear from this case report that moments perceived as ELs are significant to both the PLWD and their caregivers. As the most proximal to ELs and experts in their own experiences, PLWD and their caregivers are critical informants to appraise ELs, and their perception of ELs should be taken into serious consideration when defining what constitutes an EL.…”

“…As there is currently no universally accepted definition for ELs, there is an ongoing discussion about the defining characteristics that constitute an EL. 5 Multiple definitions have been presented in published literature, and the distinction between paradoxical and/or terminal lucid episodes in particular, is an active area of discussion. 12 A widely circulated definition from the National Institute on Aging Workshop on Lucidity in Dementia highlights paradoxical lucidity as "unexpected, spontaneous, meaningful, and relevant communication or connectedness in a patient who is assumed to have permanently lost the capacity for coherent verbal or behavioral interaction due to a progressive and pathophysiologic dementing process."…”

“…12 In addition, a preliminary research framework for investigating lucidity in dementia broadly states that restricting inquiry into lucidity to "remarkable" and "spontaneous" events in advanced dementia may prematurely narrow the definitional scope of what is and what is not an EL. 5 A more general definition for EL was provided by Norman and colleagues, who define an EL as an episode where the person seems to be more aware of their situation and functions more adequately than usual, which is surprising to observers. 3 It is possible that a broader definition of lucidity as a phenomenon with various presentations (paradoxical, terminal, and other) may be more appropriate in these early stages of investigating lucidity, as the findings from this case report suggest that the specific ways that ELs are manifested may be diverse, and may present differently in people living with mild dementia compared with people living with severe dementia.…”

“…Although there is no universal definition for the phenomena, the episodes of lucidity (ELs) have been described by an interdisciplinary workgroup of researchers convened by the National Institute on Aging as spontaneous and transient returns to the prior levels of functional or communicative abilities have been reported, although their underlying mechanisms, course, and presentation remain poorly understood. [1][2][3][4][5] Recent studies focused on appraising caregiver experiences with ELs have found that although caregivers largely view ELs as positive moments, some reported mixed feelings or greater stress after ELs. 6,7 As research on ELs is in the very early stages, reports elucidating the full range of potential impacts of ELs on people living with dementia (PLWD) are lacking despite being essential to preparing caregivers to respond to ELs and anticipate potential consequences of interventions that may attempt to stimulate ELs.…”

“…The cognitive and functional losses associated with Alzheimer disease and related dementias are generally thought to be progressive and irreversible. Although there is no universal definition for the phenomena, the episodes of lucidity (ELs) have been described by an interdisciplinary workgroup of researchers convened by the National Institute on Aging as spontaneous and transient returns to the prior levels of functional or communicative abilities have been reported, although their underlying mechanisms, course, and presentation remain poorly understood 1–5. Recent studies focused on appraising caregiver experiences with ELs have found that although caregivers largely view ELs as positive moments, some reported mixed feelings or greater stress after ELs 6,7.…”