Page 68 - GTM-3-4

Global Translational Medicine

ORIGINAL RESEARCH ARTICLE
A simple manual neck examination predicts

the apnea-hypopnea index obtained from
polysomnography

Alan B. Douglass * and Mark Kaluzienski 3
1,2
1 Department of Psychiatry, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
2 Department of Sleep Research, University of Ottawa Institute of Mental Health Research, Ottawa,
Ontario, Canada
3 Department of Psychiatry, The Ottawa Hospital, Ottawa, Ontario, Canada

Abstract

While questionnaires are common ways to screen patients suspected of having sleep
apnea, the “gold standard” of diagnosis by nocturnal polysomnography is not easily
available in many clinical settings. This is particularly true outside of Europe and North
America. Even in the latter, there are long waiting lists for assessment and the costs
of polysomnography are high. In this study, we created a new screening test based
on a simple physical examination that we called the Douglass gagging test (DGT). It
involved the clinician pressing lightly on a seated patient’s anterior neck above the
thyroid cartilage while the patient inspired deeply. Airway breath sounds were rated
on a five-point scale. Using this scale with a series of 224 consecutive patients referred
to an urban sleep disorders center, we successfully predicted the severity of the apnea-
hypopnea index (AHI) as measured by polysomnography. Using multivariate Poisson
*Corresponding author: regression, the DGT was then compared to the ability of other rating scales that are
Alan B. Douglass based on physical examination to predict AHI: the Friedman tonsil size scale (rated 0
(adouglas@uottawa.ca)
– 4), and the modified Mallampati scale (classes 1 – 4) which assesses visibility of the
Citation: Douglass AB, soft palate. Other predictors included sex, age, Epworth sleepiness scale (ESS), and
Kaluzienski M. A simple manual
neck examination predicts the body mass index (BMI). The regression coefficients showed strong prediction of AHI
apnea-hypopnea index obtained by the DGT and weaker prediction by age, sex, and BMI. There was non-significant
from polysomnography. Global prediction by the Friedman and Mallampati scales. In conclusion, this simple test,
Transl Med. 2024:3(4):4548.
doi: 10.36922/gtm.4548 which requires only 30 s to perform, constitutes a viable clinical screening tool for
sleep apnea. It might be particularly useful in rural or underdeveloped areas where
Received: August 16, 2024
Accepted: October 28, 2024 complex diagnostic equipment such as the polysomnogram is not easily available.
Published Online: November 14, Further investigation of the DGT in larger samples and different populations is
2024 warranted.
Copyright: © 2024 Author(s).
This is an Open-Access article
distributed under the terms of the Keywords: Sleep apnea diagnosis; Airway sounds; Mallampati score; Friedman tonsil
Creative Commons Attribution index; Oropharynx; Tongue base; Polysomnography
License, permitting distribution,
and reproduction in any medium,
provided the original work is
properly cited.
Publisher’s Note: AccScience 1. Introduction
Publishing remains neutral with Since the original description of obstructive sleep apnea (OSA) by Guilleminault et al.
regard to jurisdictional claims in 1
published maps and institutional at Stanford University Sleep Disorders Center, where the nocturnal polysomnogram
2
affiliations. (NPSG) was developed in the late 1970s, this previously unrecognized condition has

Volume 3 Issue 4 (2024) 1 doi: 10.36922/gtm.4548