Abstracts

Rationale: Co-morbid OSA is frequent in epilepsy, and treatment with nCPAP may reduce seizure frequency but the degree of impact on seizure outcomes remains unclear. We hypothesized that seizure frequency would be reduced by nasal continuous positive airway pressure (nCPAP) therapy in epilepsy patients with co-morbid obstructive sleep apnea (OSA). We aimed to analyze the impact of nCPAP therapy on seizure frequency.Methods: We retrospectively analyzed 184 epilepsy patients who underwent polysomnography between 1/1/00-5/30/09. Demographic, seizure frequency, antiepileptic drug load, and PSG variables were recorded. Seizure frequency was compared between epilepsy patients with OSA (apnea-hypopnea index (AHI)>5/hour) who were compliant with nCPAP and those who either deferred nCPAP or were non-compliant. Group comparisons were analyzed with 2-tailed T-tests or Wilcoxon signed rank tests in JMP or SAS (Chicago, IL).Results: 110 (60%) epilepsy patients had OSA. Average AHI was 22.4 +/- 20.8/hour. Forty-three patients received nCPAP. Of 33 patients having pre- and post-nCPAP data, seizure frequency decreased significantly (t=2.138, p=0.04). 79% reported seizure reduction and 61% were responders (having a 50% or greater seizure reduction), and this effect held when antiepileptic drugs were unchanged or reduced (n=18, p=0.01). In patients who did not receive or comply with nCPAP therapy, there was no significant difference in seizure frequency (n=28, t=-1.411, p=0.17). Seizure-freedom was significantly more likely in CPAP treated patients (OR=5.5, 95% CI=1.1-29.4, p=0.04).Conclusions: nCPAP treatment significantly reduces seizure frequency, and the degree of seizure improvement appears comparable to the effect of adjunctive antiepileptic drug therapy. Seizure-freedom was 5-fold more likely in CPAP treated patients. Further prospective studies of the impact of co-morbid OSA in epilepsy patients on seizure burden and interictal state factors crucial to quality of life are warranted.