Folie à Deux in the Aged: Review and Case Report of Role Reversal

ABSTRACT: The English literature on folie à deux in patients over 65 is reviewed, and a case in two sisters who reversed dominant and submissive roles in old age is presented. The common concept of folie à deux as an imposed entity should be de‐emphasized in favor of the concept that the preservation of a critical close relationship is the primary etiological factor in most unitary delusion systems of long duration. Apparently the syndrome is similar in both old and young, but folie‐à‐deux relationships in the elderly seem to have a particularly strong interdependent and psychotic character, with a high ratio of folie simultanée. This weak ego state should be kept in mind when planning treatment.