Effect of recording duration on the diagnostic accuracy of out-of-center sleep testing for obstructive sleep apnea.
OBJECTIVE
This study investigated the minimum recording time needed during out-of-center sleep testing (OCST) to accurately diagnose the presence and severity of obstructive sleep apnea (OSA).


METHODS
A retrospective analysis was conducted of OCSTs performed from October 2009 to May 2012 at the Mayo Clinic Center of Sleep Medicine using the portable Embletta™ system.


METHODS
Demographic information was collected for patients who underwent OCSTs during the study period, including presenting symptoms, examination findings, and comorbidities.


METHODS
Each study was divided into 60-, 120-, 180-, 240-, 300-, 360-, and 420-min intervals beginning at the recording start time to determine the respiratory event index (REI) for each of these time intervals. These interval values were then compared to the original REI derived from the total recording time (REITRT) by a paired t-test and concordance correlation coefficient (CCC).


RESULTS
There were significant differences between the REITRT and the REI from the 60-min (P < 0.0001), 120-min (0.0001), 180-min (0.003) and 240-min (0.006) intervals with a lack of concordance, suggesting these intervals are poor diagnostic correlates for the REITRT. REIs determined at 300, 360, and 420 min were not significantly different from the REITRT and had highly significant CCCs, 0.963, 0.987, and 0.995, respectively.


CONCLUSIONS
The results suggest that at least 300 min recording time during out-of-center sleep testing is needed for accurate diagnosis of obstructive sleep apnea and determination of obstructive sleep apnea severity.
Center for Sleep Medicine, Mayo Clinic, Rochester MN.
Lara M
LM
Wittine
Center for Sleep Medicine, Mayo Clinic, Rochester MN ; Division of Pulmonary and Critical Care Medicine, Mayo Clinic, Rochester MN.
Eric J
EJ
Olson
Center for Sleep Medicine, Mayo Clinic, Rochester MN ; Division of Pulmonary and Critical Care Medicine, Mayo Clinic, Rochester MN.
Timothy I
TI
Morgenthaler
D015897:Comorbidity; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017286:Polysomnography / Q000379:methods*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012890:Sleep; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis* / Q000503:physiopathology; D013997:Time Factors
home sleep test; obstructive sleep apnea; out-of-center sleep test