Could obstructive sleep apnea be diagnosed in children with Down syndrome utilizing biomarkers?

Researchers from Massachusetts General Hospital (MA, USA) have been investigating the possibility of using urinary biomarkers as a means to diagnose obstructive sleep apnea (OSA) in children with Down syndrome. These findings could mean an end to expensive and time consuming sleep studies.

Speaking of the benefits, co-director of the Down syndrome program at Massachusetts General Hospital, Brian Skokto, commented: “It would be such a low-cost way of screening for apnea that would save many patients and their families the hassle and discomfort of an overnight sleep study.”

The study, published online in Sleep Medicine, have identified a series of 12 neurotransmitter biomarkers that have shown promise in distinguishing OSA in individuals with Down syndrome. For these individuals, OSA can be a serious condition which can result in cardiovascular problems such as hypertension and arrhythmia, in addition to metabolic problems.

As part of the investigation, the team collected 58 urine samples from children with Down syndrome, prior to their scheduled overnight polysomnogram. Of the 58 samples collected, 47 were sex- and aged- matched with 43 samples taken from neurotypically developing controls.

It was found that elevated concentrations of urinary biomarkers were observed in the patients who had Down syndrome, in contrast to the healthy controls. It was also observed that a biomarker signature consisting of 4 urinary biomarkers could predict whether a child with Down syndrome had an abnormal apnea-hypopnea index, which would indicate OSA. The team found a predictive success rate of 90% for a positive prediction amongst the cohort and a 68% negative predictive value.

Although the initial results are promising, Skokto stressed that these results are still in the preliminary stages. He explained that “before they can be used in clinical practice, we will need to validate these findings in a new group of patients with Down syndrome, which we are working on right now.”

It is hoped that further investigation with a larger cohort will confirm the initial results, so that eventually a simple urine test could determine whether or not a child with Down syndrome has OSA.

Sources: Elsharkawi I, Gozal D, Macklin EA, Voelz L, Weintraub G, Skotko B.  Urinary biomarkers and obstructive sleep apnea in patients with Down syndrome. Sleep Medicine. 34 84-89 (2017) doi:10.1016/j.sleep.2017.02.005; www.massgeneral.org/about/pressrelease.aspx?id=2084