Apathy is more severe in vascular than amnestic mild cognitive impairment in a community: The Kurihara Project

Aim: The aim of this study was to estimate the prevalence of apathy, and to compare vascular mild cognitive impairment (vMCI), amnestic MCI (amMCI), and other type using Clinical Assessment for Spontaneity (CAS). Methods: Agreement to take part in the study was obtained from 590 community dwellers, aged ≥75 years living in Kurihara, Japan. Of the 590 subjects, 221 had a clinical dementia rating (CDR) of 0 (normal); 295 had CDR 0.5 (mild cognitive impairment; MCI); and 74 had CDR 1+ (dementia). The CDR 0.5 subjects were divided into three groups: 55 with vMCI (Erkinjuntti et al. criteria), 91 with amMCI and 149 with other type. To evaluate the various aspects of apathy, we used the three CAS subscales: clinical interview (CAS1), self-evaluation (CAS2), and caregiver assessment (CAS3). Three analyses were then performed to determine: (i) the validity of CAS; (ii) the prevalence rate of apathy in CDR 0 versus CDR 0.5 versus CDR 1+; and (iii) the prevalence rate of apathy in normal versus vMCI versus amMCI versus other type. Results: CAS was validated with the Apathy Evaluation Scale. There were significant differences among the three CDR groups in CAS1, CAS2 and CAS3 (P < 0.001). The prevalence rate of apathy in each CAS in the CDR 1+ group was higher than the CDR 0.5 group, which was higher than the CDR 0 group. There was a significant difference in CAS3 score between the four groups (the normal and the three subgroups; P < 0.001). Apathy in vMCI was more severe than in the other three groups (P < 0.05) on CAS3 score. Conclusions: vMCI subjects have more severe apathy compared with amMCI subjects on caregiver assessment.