Tongue biting in epileptic seizures and psychogenic events: an evidence-based perspective

Tongue biting (TB) may occur both in seizures and in psychogenic non-epileptic events (PNEEs). We undertook a systematic review to determine sensitivity, specificity, and likelihood ratios (LR) of TB. Five studies (222 epilepsy patients and 181 subjects with PNEEs) were included. There was a statistically significant higher prevalence of TB (both without further specifications on site of lesions and lateral TB) in patients with seizures. Pooled accuracy measures of TB (no further specifications) were sensitivity 38%, specificity 75%, pLR 1.479 (95% CI 1.117-1.957), and nLR 0.837 (95% CI 0.736-0.951). Pooled measures of lateral TB were sensitivity 22%, specificity 100%, pLR 21.386 (95% CI 1.325-345.169), and nLR 0.785 (95% CI 0.705-0.875). Only a pooled analysis of data demonstrated a statistically significant pLR for lateral TB. Lateral TB but not 'any' TB has diagnostic significance in distinguishing seizures from PNEEs, supporting the diagnosis of seizures. Tongue biting without further specifications has, therefore, no value in the differential diagnosis between seizures and PNEEs.