Authors :
Shan He, DO – University of Kansas Medical Center
Kelsey Sewell, PhD – University of Kansas Medical Center
Laura Heckert, MD – University of Kansas Medical Center
Gary Gronseth, MD – University of Kansas Medical Center
Presenting Author: Carol Ulloa, MD – The University of Kansas Medical Center
Rationale:
Iron deficiency has been associated with behavioral and cognitive effects across the lifespan. Functional Neurological Disorder (FND), a condition affecting nervous system function without detectable structural abnormalities, often occurs in the context of behavioral or psychosocial factors. Mean Corpuscular Volume (MCV) measures the average size of red blood cells and is commonly decreased in iron deficiency. This study aims to explore a possible link between iron deficiency and FND. MCV is used as a surrogate measure of iron deficiency.
Methods:
Following IRB approval, we performed a retrospective chart review of patients admitted to a single-center Epilepsy Monitoring Unit (EMU) between April 2024 and April 2025. Thirty-seven FND patients were identified and matched by age group (10 year band distribution) and gender to epilepsy patients using a random number generator. Each patient’s Complete Blood Count (CBC) and Electroencephalography (EEG) findings were reviewed and documented. An independent samples t-test assuming equal variances was conducted to compare group means for MCV as well as other values in the CBC.
Results:
The average age was 38.8 years in the FND group and 39.6 years in the epilepsy group, with both cohorts comprising 29 females and 8 males. The mean MCV was 87.3 fl in the FND group and 90.8 fl in the epilepsy group. The mean MCV was 3.5 fl lower in the FND group compared to the epilepsy group. (Raw Mean Difference = -3.5; 95% CI: -6.1 to -0.9). This difference is statistically significant given CI is below 0.
Conclusions:
Patients with FND have significantly lower MCV compared to matched epilepsy patients. This suggests a potential association with iron deficiency or related hematological abnormalities. Given the behavioral and cognitive implications of iron deficiency, these findings highlight the need for further investigation into iron status in FND. We plan to conduct prospective studies with larger cohorts and expanded iron panel testing (e.g., ferritin, transferrin saturation, iron binding capacity) to clarify this relationship and inform clinical management.
Funding: none