Anosognosia is associated with increased prevalence and faster development of neuropsychiatric symptoms in Mild Cognitive Impairment

Abstract

AbstractBackgroundBoth the loss of awareness for cognitive decline (a.k.a anosognosia) and neuropsychiatric symptoms (NPS) are commonly seen in patients with Alzheimer’s disease (AD) dementia, even in the prodromal stages. Anosognosia and NPS may negatively affect caregiver burden and patient’s activities of daily living. Despite the high impact of these symptoms on patients and their caregivers, our knowledge of how they develop across the AD spectrum is limited. Here, we explored the cross‐sectional and longitudinal associations between anosognosia and NPS in individuals with mild cognitive impairment (MCI).MethodWe included 310 participants from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) with a baseline Clinical Dementia Rating global score of 0.5. Everyday Cognition (ECog) questionnaire scores were used to measure complaints from participants and study‐partners at baseline and annually over a mean of 4 years (SD = 3). Anosognosia was defined as the study‐partner having an ECog score ≥2.5/4 and the participant having an ECog score ≤2.5/4 on their baseline measure and their last observation and without having more than 2 consecutive deviating observations during the follow‐up period. The 12 study‐partner‐rated Neuropsychiatric Inventory items determined the presence or absence of specific NPS (see Table 1). The Mini‐Mental State Examination (MMSE), an assessment used to screen for cognitive impairment, was administered annually. Survival analyses were performed to analyze the rate of appearance of NPS over time in individuals with and without anosognosia.ResultSixty participants displayed anosognosia, while 250 did not. At baseline, groups had similar lengths of follow‐up. Participants with anosognosia had lower MMSE scores and a higher proportion of amyloid positivity (see Table 1). At baseline, the frequency of agitation and disinhibition was higher in the anosognosia group. Survival analyses showed earlier onset of all NPS in the anosognosia group (see Figure 1). Specifically, aberrant motor behavior, irritability, disinhibition, apathy, agitation, and hallucinations were highly significant.ConclusionLoss of awareness for cognitive decline is associated with greater frequency and faster onset of NPS over time in participants with MCI. These results support the hypothesis of a potential common underlying neurophysiological process, a finding that needs to be addressed further in future studies.