Functional cognitive disorder in subjective cognitive decline-A 10-year follow-up

Area of Science:

• Neurology
• Cognitive Science
• Psychiatry

Background:

• Subjective cognitive decline (SCD) is common in memory clinics, with a subset at higher dementia risk.
• Functional cognitive disorder (FCD) is a somatoform condition within the SCD group, affecting at least 11% of attendees.
• The heterogeneity of SCD necessitates differentiating conditions like FCD to accurately assess dementia risk.

Purpose of the Study:

• To determine if patients diagnosed with FCD have an increased risk of developing dementia over time.
• To evaluate the long-term diagnostic utility of the Schmidtke criteria for FCD in predicting dementia progression.

Main Methods:

• A cohort of 42 patients diagnosed with FCD at a university memory clinic were followed for 10 years.
• Follow-up included interviews, depression screening, and neuropsychological testing (verbal memory, processing speed).
• Cognitive impairment was defined as performance below 1.5 standard deviations from the age-related mean.

Main Results:

• Of 42 patients, 28 (67%) participated in the 10-year follow-up; 10 (24%) were contacted and dementia excluded; 4 (10%) were lost to follow-up.
• Cognitive measures remained stable over the decade, with all participants performing within normal limits (within 1.5 SD).
• No participants who could be contacted showed signs of dementia after 10 years.

Conclusions:

• The Schmidtke criteria for FCD effectively identified individuals with subjective cognitive decline who did not progress to Mild Cognitive Impairment or dementia.
• Functional cognitive disorder, as diagnosed by these criteria, does not appear to confer an increased risk for dementia over a 10-year period.