Lack of awareness, also known as anosognosia, refers to the difficulties experienced by patients with certain neurological conditions, including Alzheimer’s disease (AD), in acknowledging their condition, symptoms and changes (Mograbi and Morris, 2018). According to Clare (2010), awareness in people with severe dementia is the ability to hold a reasonable or realistic perception or appraisal of, and/or respond accordingly to, a given aspect of their environment, situation, functioning or performance. Studies have sought to assess the progression of awareness of disease through cross-sectional or longitudinal designs.

The main finding of cross-sectional studies has been that lack of awareness increases as AD progresses (Starkstein et al., 2006; Maki et al., 2012; Mograbi et al., 2012; Conde-Sala et al., 2014; Baptista et al., 2019). A decline in awareness has been observed independent of the type of evaluation used (e.g., comparison of a patient and a relative, Starkstein et al., 2006; Maki et al., 2012; Conde-Sala et al., 2014; Baptista et al., 2019; the prediction-performance paradigm, Mograbi et al., 2012) as well as the stage of disease studied. However, the examination of a narrow time frame under a cross-sectional design does not allow potential fluctuations to be discerned over a stage of life that extends over years and months. To examine a time frame that more closely reflects what is experienced in institutions, some studies have employed a longitudinal perspective.

Similar to the cross-sectional studies, longitudinal studies have mainly observed an increased lack of awareness over time (McDaniel et al., 1995; Aalten et al., 2006; Clare and Wilson, 2006; van Vliet et al., 2013; Turró-Garriga et al., 2016; Sousa et al., 2017; Hanseeuw et al., 2020). This progressive loss of awareness is not the only pattern that has been observed. Indeed, Clare and Wilson (2006) and Turró-Garriga et al. (2016) observed a progressive loss of awareness for some participants and stability in awareness, albeit to a lesser extent, for others. Recently, Dourado et al. (2016) observed that nearly a quarter of the sample exhibited a deficit at the 1-year point but found an improvement in awareness for 12.3% of the sample. Taken together, these longitudinal studies indicate different patterns of change in awareness of disease. When the amount of time between measurements is reduced, the observed variation in patterns tends to increase, thereby raising the question of whether the intervals of assessment should be further reduced (e.g., monthly, weekly, or even daily follow-up). Some studies have reported the daily experiences of relatives (Clare and Woods, 2005; Walmsley and McCormack, 2017) and reported “moments of lucidness,” “flashes,” or alternation between “moments of presence and moments of absence” (Rozotte, 2001). In their qualitative study, Wawrziczny et al. (2016) highlighted the changing nature of the symptoms and the discourse of spouses with dementia about their symptoms. If the discourse of people with the disease evolves on a small time scale, a caregiving spouse can be expected to see changes from 1 day to the next, or family members visiting a loved one in a nursing home can be expected to see changes in discourse from week to week or month to month. These discourses may reflect varying awareness levels of the patient. To our knowledge, no study has measured awareness of disease at such short intervals.

Previous cross-sectional and longitudinal studies have had limitations, such as the use of different samples, in the comparison of stages and long intervals between evaluations. The occurrence of daily fluctuations reported in some studies was based only on comparative assessments. Indeed, another limitation is the quasi-systematic use of comparative methods to evaluate awareness, such as with the use of clinical ratings (McDaniel et al., 1995; van Vliet et al., 2013), the prediction-performance paradigm (Mograbi et al., 2012; Avondino and Antoine, 2015), and/or comparison of a patient’s assessment with that of a relative (Starkstein et al., 2006; Baptista et al., 2019; Hanseeuw et al., 2020). Although the information gained from such comparative methods is necessary and useful for understanding what the person with AD experiences, the perspective of the individual, what he or she understands about him- or herself and his or her evolution, and how this is expressed in his or her discourse deserve to be further explored. Finally, these evaluations tend to consider only one facet of awareness, namely, objects, the “what” that the evaluation is based on. In dementia research, several studies have even emphasized the need to distinguish between objects of awareness (Dourado et al., 2007; Markova et al., 2014), for example, by differentiating awareness of cognitive functioning and health condition, activities of daily living, emotional state, social functioning, and relationships (Lacerda et al., 2018). In the present study, objects refers to the basis of changes and new information (emotions, body, communication, autonomy, identity, cognitive abilities, memory, and AD) perceived by people with AD (Mayelle et al., 2019). Furthermore, O’Shaughnessy et al. (2021) stated that awareness is a multidimensional construct requiring a holistic approach. The phenomenon of awareness appears to be more than merely a “what” but rather a synergy associating the “what” (i.e., the objects of awareness) with the “how” in terms of the mechanisms and modes of expression underlying awareness (Mayelle et al., 2020).

Two key issues must be addressed. The first is the need to reduce the intervals of the observation of awareness to better approximate the patient’s experiences, including the investigation of objects, mechanisms, and modes of expression. The second is the need to obtain a sense of awareness as experienced by people with AD through a person-centered approach, i.e., based on their discourse reflecting their own perceptions and the meaning they assign to those perceptions. We propose two hypotheses. The first concerns the observation of different “profiles” of awareness characterized by the awareness of objects and the presence of mechanisms and modes of expression. While we hypothesize that both fully “aware” and “unaware” profiles will be observed, we also expect to observe more nuanced profiles that exhibit differences in terms of awareness of objects, mechanisms and modes of expression. The second hypothesis concerns fluctuations in awareness. Based on the patterns of fluctuations observed in longitudinal studies, we hypothesize that the profiles of awareness identified will exhibit three different types of patterns: deficit, stability, or improvement.

Research on awareness in AD provides information regarding its heterogeneity and temporality. However, it does not allow appreciation of the heterogeneity of the processes of awareness (Mayelle et al., 2019, 2020) and daily fluctuations in awareness. The first part of this work involved the observation of different profiles of awareness characterized by the awareness of objects and the presence of mechanisms and modes of expression. The second part of this work involved the observation of weekly fluctuations in these aspects.

We first hypothesized that profiles of awareness would range from extremes (i.e., aware vs. unaware) to more mixed profiles. We observed five different profiles, two of which indicated complete awareness and lack of awareness. The other three profiles differed mainly in terms of the use (i.e., frequency and adaptation) of mechanisms and modes of expression of awareness. Based on these results, we were able to confirm that awareness in AD is heterogeneous, highlighting distinct levels of awareness both in terms of objects (the “what”) and processes (the “how”) that characterize the disease (Mayelle et al., 2020).

In the second part of the study, our results were consistent with prior results, and they provide evidence of the non-linearity of awareness (Lacerda et al., 2020). While we were able to show that each participant exhibited a unique temporal trajectory of fluctuation(s) in awareness, the analysis of the transitions between the profiles revealed a number of trends. We observed that the profiles of awareness tended to remain stable between measurement times. However, the profiles could improve or worsen for certain components (i.e., objects, mechanisms, and/or modes of expression). Furthermore, while a high general level of awareness could become very low in the short period between measurements, a low level of awareness could not become very high.

Similarly, we noted that the highest probability of change was related to a slight improvement in the level of awareness of objects and the presence of modes of expression. For this particular fluctuation, we proposed three interpretations.

First, one perspective on this improvement is the concept of the petrified self (Mograbi et al., 2009). It is possible that when confronted with a mistake or criticism, a resident became temporarily aware of his or her condition or its evolution. However, the long-term integration of this new information would fail, resulting in a return to a lower level of awareness at the next interview.

Second, after returning to the interviews, we assumed that this fluctuation was specifically linked to events and/or changes in the environment and the participant’s daily life (e.g., a room change). A person exhibits a specific profile of awareness that is influenced by an environmental change. Once this change becomes established, the person returns to the initial level, which translates into a deficit followed by an improvement. This interpretation particularly reflects changes in the integration and rejection of the disease as characteristic of the self (Pearce et al., 2002; Frazer et al., 2012). O’Shaughnessy et al. (2021) suggested that people with severe AD may not demonstrate awareness, not because they are unable to but rather because environmental factors are not conducive to expressing awareness.

Third, the relevant interviews tended to highlight the influence of the investigator and his or her attitude toward awareness. When a person has disorganized speech, the practices of reformulation, the verbalization of a thought, or the stimulation of verbal exchanges appear to help him or her express him- or herself in a more suitable and coherent manner, thereby restoring meaning (Ducato et al., 2013). According to the ASDA (e.g., Table 1), this process can be translated, for example, into the expression of changes with a self-description, the expression of doubts about daily life and the future, or the expression of a need for help. To best verify this effect, the ASDA could be made part of an interventional protocol employing dignity therapy (Martínez et al., 2017) or validation therapy (Neal and Barton Wright, 2003). These two approaches aim to support the person with AD with caring verbal expression to encourage him or her to integrate these events and give them meaning. A pre- and postintervention ASDA evaluation of awareness could quantify the effect of others’ attitudes on awareness.

Our data allowed the modeling of fluctuations in awareness of disease that have often been studied from the perspective of patients’ relatives (Rozotte, 2001; Clare and Woods, 2005; Walmsley and McCormack, 2017). The presentation of these profiles and their possible fluctuations to health professionals could allow these professionals to verbalize their daily experience in care and help them understand the relative instability of the patient’s perspective and therefore the need to repeat the interactions to understand the extent of that fluctuation. For example, the implementation of the methodology employed in the present study on a case-by-case basis in residential care facilities could allow caregivers to understand and then adjust to the reactions of people with AD while they provide support. Indeed, caregivers evolve in a reality that differs from that of the person with AD (Hertogh et al., 2004), and they can find themselves powerless when confronted with a refusal of care or only partial observance of treatment for which they do not understand all of the underlying processes (Fischer et al., 2019).

However, increasing the sample size appears to be necessary to reinforce the validation of the identified profiles of awareness. Such an increase in the sample size would also allow more clusters and hence more nuances in the profiles to be identified. Furthermore, an increase in the sample size would allow confirmation and increase the generalizability of the possible trajectories observed. Although the sample reflects the overrepresentation of women living in nursing homes, an increase in the number of male participants would allow verification of the impact of gender on awareness (Liu et al., 2017) and the distribution of the profiles. Indeed, the limitations of the study are linked mainly with the characterization of the sample and the impact of these parameters on the profiles of awareness and their possible fluctuations. As this was a pilot study, we essentially collected data centered on awareness without collecting information regarding education level, time since diagnosis or time living in a nursing home, the severity of the disease, neuropsychiatric symptoms (Yoon et al., 2017) or personality (Rankin et al., 2005). Now that this study has shown fluctuations in awareness, it is important to control, for example, the cognitive profile of the participants to understand the role played by these variables in the awareness profiles.

This study aimed to understand the awareness of self and disease in people with AD by adopting a perspective based on profiles rather than a single score. These profiles were studied on the basis of their fluctuations from a restricted temporal perspective. Multiple profiles and trajectories were identified, illustrating inter- and intraindividual variability in awareness. These results confirm the need to focus on the subjective experience of the person with assessment intervals that closely reflect his or her daily life.

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

The studies involving human participants were reviewed and approved by the Ethics Committee of the University of Lille (2018-267-S58). The patients/participants provided their written informed consent to participate in this study.

AM and PA were responsible for the conception and design of the study and responsible for the drafting of the manuscript. AM, CH, MEH, DM, and PA contributed to the collection and analysis of data. All authors critically revised the draft and approved the final version.

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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