Higher Rates of Sleep Apnea in Patients with Idiopathic Intracranial Hypertension

Andreas Yiangou, BSc, MBBS

Patients with idiopathic intracranial hypertension (IHH) are at an increased risk of obstructive sleep apnea (OSA), according to new research based in the UK.

A team, led by Andreas Yiangou, BSc, MBBS, Metabolic Neurology, Institute of Metabolism and Systems Research, College of Medical and Dental Sciences, University of Birmingham, determined the prevalence of obstructive sleep apnea in patients with idiopathic intracranial hypertension, while evaluating the diagnostic performance of obstructive sleep apnea tools in this patient population and the relationship between weight loss and the 2 diseases over 1 year.

The Link Between Diseases

Obesity is a known risk factor for a number of diseases, including obstructive sleep apnea and idiopathic intracranial hypertension. IHH is raised intracranial pressure in the absence of an identifiable cause that occurs generally in young women with obesity. Symptoms can include headache, transient visual obscurations, pulsatile tinnitus, cognitive disturbances, back and neck pain, and diplopia.

The incidence of any degree of OSA in the general population is between 9-38%, but is higher with increasing age, body mass index, and the male gender.

“A co-morbid relationship between IIH and OSA is well described but how commonly this occurs and the relevance to IIH is uncertain,” the authors wrote.

Examining the Data

In the sub-study of a multi-center, randomized controlled parallel group study, the investigators compared the impact of bariatric surgery with community weight management interventions on IIH-related outcomes over 12 months. They also assessed obstructive sleep apnea, defined as an apnea–hypopnea index (AHI) ≥ 15 or ≥ 5 with excessive daytime sleepiness (Epworth Sleepiness Scale ≥11 ), using a home-based polygraphy at baseline and 12 months.

There were 66 women with IHH identified, with 46 included in the study. The prevalence of obstructive sleep apnea was 47% (n = 19). The STOP-BANG had higher sensitivity (84%) compared to both the Epworth Sleepiness Scale (69%) and Berlin (68%) to detect obstructive sleep apnea.

The Comparison

In addition, bariatric surgery resulted in greater reduction in the apeana-hypopbea index compared to the community weight management intervention group (median AHI reduction of – 2.8; 95% CI, –11.9 to 0.7; P = 0.017).

At the 12 month mark, there was a positive association between changes in papilledema and AHI (r = 0.543; P = 0.045). This remained true even after adjusting for changes in the body mass index (R² = 0.522, P = 0.017).

“Our data also suggests that treating OSA in patients with IIH may improve papilledema,” the authors wrote. “The high prevalence of OSA in IIH is greater than previously reported in the historical literature. The higher prevalence in our cohort may reflect the larger cohort size but also trends for increasing BMI amongst IIH patients in line with the global obesity epidemic.”

The authors said more research is needed to evaluate whether obstructive sleep apnea treatment has a beneficial impact on papilledema, the swelling of the optic nerve.

The study, “Obstructive sleep apnea in women with idiopathic intracranial hypertension: a sub-study of the idiopathic intracranial hypertension weight randomized controlled trial (IIH: WT),” was published online in the Journal of Neurology.