Prevalence and correlates of Capgras syndrome in Alzheimer's disease

Objectives. This study examined the prevalence and clinical correlates of C apgras syndrome (CS) in Alzheimer's disease. Design. Cross-sectional study of elderly patients evaluated at an outpatien t memory disorders clinic classified according to the presence or absence o f CS. Subjects. One hundred and fifty-one consecutive patients diagnosed with pro bable (N = 110) or possible (N = 48) Alzheimer's disease (AD) utilizing NIN CDS-ADRDA diagnostic criteria. Materials. The Behavioral Pathology in Alzheimer's Disease Rating Scale (BE HAVE-AD), Mini-Mental State Examination (MMSE) and Blessed Dementia Scale ( BDS). Results. CS was observed in 10% of the sample (N = 16). Associated factors included other delusions, lower MMSE scores and higher BDS scores. The rela tion between CS and both cognitive and functional status remained significa nt after controlling for other delusions. Conclusion. CS was prevalent in approximately 10% of our community-dwelling AD sample. This syndrome was more common at the later stages of the illnes s and showed relations with increased functional impairment and other psych otic symptomatology. Copyright (C) 1999 John Wiley & Sons, Ltd.