Number of patient-reported allergies helps distinguish epilepsy from psychogenic nonepileptic seizures

Abstract

Summary Psychogenic non-epileptic seizures (PNES) are relatively common, accounting for 5–40% of visits to tertiary epilepsy centers. Inpatient video electroencephalogram (vEEG) monitoring is the gold standard for diagnosis, but additional positive predictive tools are necessary given vEEG’s relatively scarce availability. In this study we investigate if the number of patient-reported allergies distinguishes between PNES and epilepsy. Excessive allergy-reporting, like PNES, may reflect somatization. Using the electronic medical record, ICD-9 codes, and text-identification algorithms to search EEG reports, we identified 905 cases of confirmed PNES and 5187 controls with epilepsy but no PNES. Patients with PNES averaged more self-reported allergies than patients with epilepsy alone (1.93 vs. 1.00, p<0.001). Compared to those with no allergies, each additional allergy linearly increased the percentage of patients with PNES by 2.98% (R2=0.71) such that with ≥ 12 allergies, 12/28 patients (42.8%) had PNES compared to 349/3368 (11.6%) of the population with no allergies (odds ratio = 6.49). This relationship remained unchanged with logistic regression analysis. We conclude that long allergy lists may help identify patients with PNES. We hypothesize that a tendency to inaccurately self-report allergies reflects a maladaptive externalization of psychologic distress, and that a similar mechanism may be responsible for PNES in some patients with somatic symptom disorder.

Medication prescriptions in 322 motor functional neurological disorder patients in a large UK mental health service: A case control study

“…mFND patients were significantly more likely to have a prescription of one or more antihistamines, and the results indicated the drug was more frequently prescribed to mFND patients as an anti-allergy and as a sedative to control patients. Previous studies have reported higher rates of self-reported allergies in PNES patients compared to epileptic patients (Robbins et al, 2016), as well as heightened sensitivities and side effects to medications (Park et al, 2014, Nassim Matin et al, 2017. The presence of increased allergy and non-specific medication side-effects in mFND deserves further examination and highlights the importance of a considered and collaborative prescription strategy (Barsky et al, 2002).…”

Avoidance in nonepileptic attack disorder: A systematic review and meta-analyses

“…This review provides evidence for a commonly held clinical opinion that avoidance should be considered within interventions when working with individuals with NEAD [70,71]. Many professionals describe difficulties working with NEAD patients [72].…”

Functional dystonia: A case‐control study and risk prediction algorithm

“…42 FD were also more likely to report ≥3 medication class allergies, meeting criteria for multiple drug intolerance syndrome. 28 A higher number of medication allergies have distinguished dissociative seizures from epilepsy 43 and predicted longer illness duration. 44 We created a practical decision tree to allow historical classification of suspected FD in adults and children.…”