Subjective Cognitive Dysfunction in Patients With and Without Fibromyalgia: Prevalence, Predictors, Correlates, and...

Area of Science:

• Rheumatology
• Neuroscience
• Psychiatry

Background:

• Subjective cognitive dysfunction (SCD) is frequently reported in fibromyalgia (FM), termed 'fibrofog.'
• Predictors and correlates of SCD in FM and non-FM populations are not well understood.
• Limited research exists on SCD and FM in the general population.

Purpose of the Study:

• Investigate predictors and correlates of SCD in clinical and general populations.
• Determine the prevalence of SCD in fibromyalgia and non-fibromyalgia patients.
• Assess the relationship between SCD and symptom severity in rheumatic diseases.

Main Methods:

• Analyzed data from 11,150 rheumatoid arthritis patients using fibromyalgia criteria and cognitive severity (CS) assessment.
• Included two cross-sectional general population studies for SCD and FM prevalence.
• Assessed CS status (CS+) and its correlation with various symptom and disease severity measures.

Main Results:

• Fibromyalgia (FM+) was present in 21.7% of clinical subjects; 52.3% of FM+ patients had CS+.
• In general populations, 42.0%-52.3% of FM+ subjects had CS+, compared to 1.4%-5.5% of FM- subjects.
• Cognitive severity (CS+) was strongly linked to symptom severity scales (SSS), a fibromyalgia criterion, and general health, not primarily pain.

Conclusions:

• SCD is associated with high somatic and psychological symptom counts.
• Symptom severity, not pain extent, is the best predictor of SCD.
• SCD, or 'fibrofog,' is not exclusive to fibromyalgia, as 43.6% of CS+ cases occurred in non-fibromyalgia subjects, suggesting a symptom severity continuum.