Background and Hypothesis

Functional seizures (FS) are episodes characterized by seizure-like events that are not caused by hypersynchronous neuronal activity. Prior studies have suggested an increased prevalence of psychotic disorders among patients with FS, but results have been inconsistent. We hypothesize that FS are associated with psychosis and that among patients with psychosis, the presence of FS may influence patient clinical characteristics, mortality, and medical resource utilization.

Study Design

The association between FS and psychosis was assessed using electronic health records data from a total of 752,883 individuals receiving care at Vanderbilt University Medical Center between 1989 and 2023. Analyses of the association between FS and psychiatric outcomes, sexual trauma, healthcare utilization, and other clinical comorbidities were conducted in a subset of 5,239 patients with psychosis.

Study Results

Odds of FS were elevated among patients with psychosis compared to controls (OR=10.17, 95% CI=8.55-12.08, p<0.001). Among patients with psychosis, those with FS exhibited higher rates of suicidality (OR=1.98, 95% CI=1.40-2.8, p<0.001), catatonia (OR=1.95, 95% CI=1.23-3.09, p=0.03), sexual trauma history (OR=2.98, 95% CI=2.08-4.26, p<0.001) and had a greater numbers of antipsychotic trials (4.56 versus 3.37, beta=1.16, SE=0.16, p<0.001) than those without FS. Furthermore, patients with comorbid FS had a greater numbers of hospital presentations at one, three, five, and ten years after receiving a psychosis diagnosis (p<0.001).

Conclusions

FS are more common among patients with psychosis and are associated with increased healthcare utilization as well as an increased prevalence of suicidality, catatonia, and certain psychiatric and medical comorbidities.