A prospective controlled study about sleep disorders in drug resistant epilepsy

To evaluate sleep disorders and chronotype in patients with drug resistant focal and generalised epilepsy compared to healthy controls.

Sixty four patients with focal and six with generalised, drug resistant epilepsy were included and compared to 70 age- and gender-matched healthy controls. Patients with any relevant comorbidity were excluded. Sleep disorders and chronotype were investigated by validated questionnaires. The impact of epilepsy on quality of life was also documented in patients.

The median Pittsburgh Sleep Quality Index (PSQI) was 4 in patients and 3 in controls (median [range], IQR; patients: 4 [1-17], 3-6; controls: 3 [0-11], 2-4; p = 0.024). Self-reported confusional arousals and probable REM sleep behaviour disorder (RBD) were more frequent in patients (30.4% vs. 8.6%, p = 0.036 and 10.6% vs. 1.4%, p = 0.030, respectively). A higher risk for possible sleep apnea was identified in patients (22.9% vs. 5.7%, p = 0.042), whereas Epworth Sleepiness Score was normal in both groups (p = 1). Chronotype, assessed by the midsleep on free days, did not differ between groups (p = 0.540). Quality of life was worse in patients with PSQI scores >5 (p = 0.016).

Self-reported confusional arousals, probable RBD and a high risk for sleep apnea occurred significantly more often in patients with drug resistant epilepsy. Sleep quality differed significantly between both groups. Whether these results are due to motor activity during nocturnal epileptic seizures, parasomnia episodes, or sleep-related breathing disorder, needs further evaluation via video-polysomnography. We could confirm, at least in some cases, the previously reported mutual relationship between sleep disorders and epilepsy.