Anosognosia in Early- and Late-Onset Dementia and Its Association With Neuropsychiatric Symptoms

Abstract

Background: The symptom anosognosia or unawareness of disease in dementia has mainly been studied in patients with late-onset dementia (LOD, ≥65 years), whereas little is known on whether it is also present in patients with early-onset dementia (EOD, <65 years). We aimed at investigating differences in anosognosia between LOD and EOD, by also studying its association with different clinical variants of EOD and the presence of neuropsychiatric symptoms.Methods: A total of 148 patients, 91 EOD and 57 LOD, were recruited and underwent extended clinical assessment and caregiver interview that included questionnaires aimed at measuring anosognosia and neuropsychiatric symptoms. Differences in anosognosia between EOD and LOD and between subgroups with different clinical variants were investigated, as well as correlation between anosognosia and neuropsychiatric symptoms. A regression analysis was applied to explore the association between anosognosia and development of neuropsychiatric symptoms during disease progression.Results: Median levels of anosognosia were not significantly different between EOD and LOD. Anosognosia increased overtime with disease progression and was higher in frontotemporal dementia patients or, more precisely, in frontotemporal dementia and Alzheimer's disease variants associated with involvement of the frontal lobes. Higher levels of early anosognosia were associated with higher frequency and severity of subsequent neuropsychiatric symptoms, in particular apathy, later in the course of the disease.Conclusion: Anosognosia is a frequent symptom of EOD, occurring in 94.5% of all-cause EOD, and it is associated with higher risk of developing neuropsychiatric symptoms during disease progression. Recognising anosognosia may be helpful for clinicians and families to reduce diagnostic delay and improve disease managment.

Episodic Memory Impairment Mediates the Loss of Awareness in Mild Cognitive Impairment

“…Within this framework, one possibility is that alterations in memory self-awareness represent an early indicator of progressive decline toward AD dementia due to increased dysfunction of the DMN. This hypothesis is consistent with previous studies relating loss of awareness in AD with DMN connectivity (Mondragón et al, 2019(Mondragón et al, , 2021, but also with the relationship between anosognosia in AD with some neuropsychiatric disorders (Spalletta et al, 2012;Tondelli et al, 2021) which have also been associated with dysfunction of the DMN (Lee et al, 2020). When looking at the groups separately, we only observed a significant correlation between awareness and EM in the MCI individuals.…”

Hesitations in Primary Progressive Aphasia

“…An overall interpretation of these two opposite behaviours is that they may form part of more general processes, such as the degree of attention speakers pay to their speech (Christenfeld and Creager 1996). We hypothesised above that the hyper-fluency in individuals with svPPA may be due to the reduced attention they pay to their speech, because of either strategic decisions (Postma 2000;Sahraoui et al 2015) or higher levels of anosognosia (Tondelli et al 2021), leading to decreased self-monitoring. It has already been reported that people with svPPA tend not to grasp for 'lost' words in a conversation (Marshall et al 2018), contrary to what is observed in the other two variants of PPA.…”

Awareness and cognitive rehabilitation in Alzheimer's disease and frontotemporal dementia

“…Awareness is a multidimensional clinical symptom frequently observed in neurodegenerative dementia, such as frontotemporal dementia (FTD) or Alzheimer's disease (AD) type dementia. 1 Patients can be more or less unaware of disturbances in cognitive, behavioral, or daily functioning. Unawareness (or anosognosia) of memory difficulties was already observed in patients with mild cognitive impairment (MCI) who progressed to AD.…”