Factors influencing confabulation in Japanese patients with Alzheimer's disease

Confabulations are often observed in patients with Alzheimer's disease (AD) and can increase family caregivers' burdens. Previous studies have focused on the relationship between confabulation and cognitive ability. However, few studies have investigated the association between confabulation and familial factors. Here, we aimed to examine whether confabulation relates to familial factors, such as the level of family caregivers' expressed emotion or the level of functioning of the family.

Twenty-seven outpatients with AD and their family caregivers participated in this study. We examined confabulations about episodic memory, semantic memory, and future planning using the Modified Confabulation Battery (MCB). We investigated correlations between scores on the MCB and scores on the Mini-Mental State Examination (MMSE), Geriatric Depression Scale (GDS), Family Attitude Scale (FAS), and the Family Adaptability and Cohesion Evaluation Scale. Multiple regression analyses were performed using the total scores on the MCB and domain-specific scores on the MCB as dependent variables, and the scores on the MMSE, GDS, and FAS as independent variables.

MCB scores were positively related to FAS scores (P < 0.01) and negatively to GDS scores (P < 0.05), but not to MMSE scores. Regarding the three domains the MCB measured, confabulation about episodic memory and future planning showed a positive relationship with FAS scores.

Family attitude was the factor most related to confabulation in our study. Patients with AD may attempt to avoid confronting family caregivers' high emotional expression through confabulation, or confabulation itself might result in high emotional expression among family caregivers. Psychoeducational or therapeutic approaches for family caregivers might reduce confabulation in patients with AD.