Treating Sleep Apnea May Subdue Seizures

Study suggests CPAP benefit in epilepsy patients with OSA

by Kristina Fiore, Deputy Managing Editor, MedPage Today December 03, 2017
Note that this study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.

WASHINGTON -- Treating obstructive sleep apnea (OSA) with continuous positive airway pressure (CPAP) may lower the risk of seizures in patients with epilepsy, researchers reported here.
In a single-center study of patients treated at the Cleveland Clinic, a larger proportion of epilepsy patients with OSA who had CPAP therapy reported at least a 50% reduction in seizures from baseline at 1 year compared with those who weren't treated, and with those who didn't have OSA (63% versus 14% and 44%), according to Thapanee Somboon, MD, of the Cleveland Clinic, and colleagues, in a poster presentation at the American Epilepsy Society meeting.
Somboon said few clinicians screen their epilepsy patients for this condition. "Neurologists don't often ask their epilepsy patients about sleep, but sleep affects everything," she told MedPage Today.
At the same time, "many people with epilepsy don't realize they have sleep apnea," she noted. "Being diagnosed is the first step towards getting effective treatment and potentially decreasing the risk of seizures."
The study results suggest that it's "important to screen every epilepsy patient [for OSA] with just a small, simple question: do you snore at night? Do you have apnea at night?" If the answer is yes, a neurologist can order polysomnography, and depending on the results and recommendations, can prescribe CPAP, she said.
In patients with epilepsy, a lack of quality sleep is tied to an increased risk for seizures. Antiepileptic drugs (AEDs) may also increase the risk of OSA, because the drugs relax upper respiratory muscles and may cause weight gain, another risk factor for OSA, the researchers said.
Somboon's group looked at records for 197 patients with epilepsy who'd had polysomnography for some sleep complaint at the Cleveland Clinic from 1997 to 2015. A total of 122 of them had OSA, while 75 did not. Of those with OSA, 73 used CPAP and 49 did not.
At baseline, those without OSA were younger, more likely to be female, and had a lower BMI than those who used CPAP and those who had untreated OSA.
In addition to the finding that more epilepsy patients with treated OSA had at least a 50% reduction in seizures from baseline, more of them also achieved "treatment success." defined as no seizure activity continued from baseline, or at least a 50% reduction from baseline in seizure activity.
This outcome occurred in 85% of those who were treated, in 55% of those who were untreated, and 65% of those who didn't have OSA (P<0.001 and P=0.007, respectively), she reported.
After adjusting for baseline seizure freedom and AED standardized dose, CPAP-treated OSA patients remained more likely to achieve treatment success than untreated OSA (OR 9.58, 95% CI 3.05 to 30.2, P<0.001) and those without OSA (OR 3.66, 95% CI 1.39 to 9.63, P=0.009), she said.
Although Somboon's group didn't see any statistically significant differences between groups at 3 or 5 years, she said there was a trend in favor of CPAP treatment. "We can't talk about significance because the number of patients is too small, since we lost a lot of them due to the retrospective nature of the study," she explained.
She said further studies that are ongoing have looked at CPAP adherence, and preliminary results show that patients who achieve treatment success have very good adherence.
Somboon noted that in addition to CPAP, there are several other treatments for OSA, including weight loss, taking a decongestant, wearing a special mouth guard to bed, and having surgery. CPAP is the most effective treatment for people with moderate to severe OSA, she said.