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Global Translational Medicine New neck examination for sleep apnea

In summary, it is possible that the DGT only detects ability of the DGT to specifically exclude SDB if it is not
OSA obstruction at the base of the tongue; alternatively, present. NPV and PPV refer to the number of patients
it might detect multi-site obstructions as noted above. In who would need to be evaluated by DGT to find one who
any case, it is possible that some sites of obstruction would merited treatment. These values vary depending on the
not be identified by the DGT, thereby producing a false- prevalence of SDB in the population studied. Finally,
negative result. The answer to this question will have to the DGT has not yet been compared to more complex
await a comparison of the DGT versus sleep manometry anatomical assessments such as cranio-facial X-ray, CT,
of the airway. MRI, or other in vivo tests such as airway sound analysis
One limitation of the present study is that it was when asleep, or airway patency under anesthesia. It is
performed with patients who were already suspected by possible that further aspects of the DGT could be brought
their referring doctor of having a sleep disorder, possibly to light by such comparisons.
OSA. They were not a random sample of the general 5. Conclusion
population; therefore, the DGT may not achieve the same
significant prediction of AHI if used for much wider The DGT has been successfully validated against the AHI
screening. This will need to be addressed in future large derived from a night of polysomnography. In addition, its
validation studies. prediction of the AHI proved to be superior to ratings of
tonsils or soft palate alone. A DGT is a simple addition
Typically, statistical regressions of the type used in
the present study are performed separately for males and to any routine physical examination, requiring minimal
females. However, considering the relatively small sample preparation by the examiner and requiring only 30 s
size of this study, it was decided to pool the sexes to get to perform. In contrast to questionnaires about sleep
results that were more statistically reliable and instead to apnea, it does not rely on the patient’s reading ability,
enter sex as one of the predictor variables in the regression language skills, or memory. In other words, the DGT is
model. Future validation studies will need to be done an objective test. However, in other studies, the FTS scale,
separately on males and females. MM scale, sex, BMI, and several self-report sleep apnea
questionnaires have also shown significant correlations to
Another limitation of this study is that it was done polysomnographic AHI, which is the gold standard. The
on North American patients whose ethnicity was DGT appears to be a novel addition to the above anatomical
overwhelmingly white-European, so the findings may evaluations, perhaps tapping a new source of variance in
not be generalizable to other racial, ethnic, or geographic the evaluation of the airway in OSA. In the absence of a
populations. Therefore, research on more diverse sleep laboratory, a general practitioner could combine
30
populations is necessary to confirm the efficacy and all of the above measures to make a rational decision on
universality of this test; these should include a reasonable whether to refer the patient to a specialist, or in an isolated
proportion of participants who do not have OSA, to setting, to consider emergent treatment.
provide an adequate “floor” for the statistical distribution.
In addition, much larger sample sizes will be required in Acknowledgments
future studies.
The authors thank Lisa Kis, Chief Technician of the Royal
The present findings are encouraging but preliminary. Ottawa Hospital Sleep Disorders Clinic and her staff of
The next step would be to do an ROC analysis of the Registered Polysomnographic Technicians for their tireless
DGT. This test would be used to define a “cut-off” DGT and accurate work on this project.
rating that corresponds to the threshold between normal
and abnormal AHI values on the NPSG. To make the Funding
analysis clinically relevant, the cutoff point should be None.
chosen so that cases regarded as positive on the DGT
would predict levels of AHI that would merit dental or Conflict of interest
CPAP treatment in a sleep disorders center. This is not to
say that milder levels of SDB such as RERAs are clinically The authors declare that they have no competing interests.
irrelevant but the purpose of the DGT is to identify the Author contributions
need for treatment of significant SDB. The ROC would
also provide values for the sensitivity, specificity, positive Conceptualization: All authors
predictive value (PPV), and negative predictive value Formal analysis: All authors
(NPV) of the DGT. Sensitivity refers to the ability of the Investigation: All authors
DGT to detect SDB if it is present. Specificity refers to the Methodology: Alan Douglass

Volume 3 Issue 4 (2024) 6 doi: 10.36922/gtm.4548