The syndrome of functional memory disorder: definition, etiology, and natural course

Am J Geriatr Psychiatry. 2008 Dec;16(12):981-8. doi: 10.1097/JGP.0b013e318187ddf9.

Abstract

Objectives: Nonorganic, functional memory disorder (FMD) is frequent in memory clinic patients, and is an important differential diagnosis to prodromal dementia. The authors propose a definition of FMD as an acquired medical and psychological condition that is closely related to psychosocial burden and distress.

Design: Prospective follow-up study, aimed to evaluate the natural course of FMD.

Setting: University hospital memory clinic.

Participants: Seventy-three patients who suffered memory deficits and psychological distress and had normal test results. Forty-six attended a follow-up examination after a mean delay of 20.1 months.

Measurements: FMD severity was assessed with a structured inventory and an overall self-rating scale. Objective performance was assessed by standardized tests of memory and attention.

Results: Identified causes of distress were overwork, interpersonal conflicts, somatic illness, adjustment disorder, dysthymia, and Alzheimer phobia. At follow-up, FMD had resolved in only six patients, and persisted in 39. Average symptom severity showed only a minor reduction.

Conclusion: FMD is, in many instances, a long-term rather than transient problem. Possible reasons include the persistence of burden factors and the failure to evade the "stress spiral" of mutual reinforcement of distress and cognitive dysfunction.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Alzheimer Disease / complications
  • Alzheimer Disease / psychology*
  • Cognition Disorders / psychology
  • Depression / complications*
  • Depression / psychology
  • Diagnosis, Differential
  • Female
  • Follow-Up Studies
  • Hospitals, University
  • Humans
  • Male
  • Memory Disorders / classification
  • Memory Disorders / diagnosis
  • Memory Disorders / etiology
  • Memory Disorders / psychology*
  • Middle Aged
  • Neuropsychological Tests
  • Prospective Studies
  • Quality of Life
  • Severity of Illness Index
  • Stress, Psychological
  • Surveys and Questionnaires
  • Syndrome