Psychogenic nonepileptic seizures and chronic pain: a retrospective case-controlled study

Psychogenic nonepileptic seizures (PNES) can be challenging to diagnose, but certain clinical features can help to distinguish PNES from epileptic seizures. The purpose of this study is to assess chronic pain and prescribed pain medication use in PNES patients.

A case-controlled, retrospective analysis was performed examining pain medication use in 85 PNES patients versus an active control group of 85 patients with idiopathic generalized epilepsy (IGE).

Chronic pain was more frequent among PNES patients (N=40) than active controls (N=10) (p<0.0001). Reported use of prescription pain medication was higher among PNES patients (N=20) versus active controls (N=6) (p=0.0048). The Positive Predictive Value of prescription pain medications for PNES patients was 76.9%. Opioid use in the PNES population was higher compared with active controls (p=0.0096). When excluding patients with a dual diagnosis of PNES and epilepsy from the latter two analyses and comparing these results to those that included this patient population, no statistically significant difference in results was found.

Patients with PNES are more likely than those with IGE to report chronic pain disorders. A history of chronic pain and opioid use among patients with seizures raises the possibility of PNES. Among patients with PNES and chronic pain, a psychogenic etiology for pain and non-opiate pain management strategies should be considered.