Diagnostic test evaluation of a nasal flow monitor for obstructive sleep apnea detection in sleep apnea research

Abstract

In this diagnostic test evaluation of a nasal flow monitoring device for obstructive sleep apnea (OSA), 34 patients referred for polysomnography were studied at home for three consecutive nights with the monitor. The mean age of subjects (±SD) was 41.9±10.3 years, and their mean apnea-hypopnea index (AHI) was 31.5±27.2. The difference between the average AHI from three nights at home on the monitor and the polysomnogram (PSG) result was 1.8±17.1. The area under the receiver operating characteristic curve (AUC) for PSG All ? 10 was .96. With a threshold AHI of 18 on the flow monitor, sensitivity was .92, specificity .86, positive predictive value .96, and negative predictive value .75. For detecting severe OSA (AIR ? 30), the AUC was .85. With knowledge of appropriate thresholds and the pretest risk of OSA, the flow monitor can be used to detect or exclude OSA for sleep-related research, as well as to identify severe cases needing priority for further evaluation.

Effectiveness of Home Single-Channel Nasal Pressure for Sleep Apnea Diagnosis

“…In contrast, OSA prevalence was higher (91%) than in similar studies. [12][13][14][15][16][17][18] While our target population and inclusion criteria differed from those of similar studies, we did not find any clear differences in variables that can influence OSA prevalence, such as degree of sleepiness, body mass index, age, and percentage of men. Our hypopnea definition from the Sleep Spanish Network 22,31 is similar (but a little less demanding) to the "alternative" definition from the American Academy of Sleep Medicine 2007, 30 and it is the same as the definition recommended by the American Academy of Sleep Medicine 2012.…”

“…Published studies of the diagnostic efficacy of HNP in comparison to conventional in-laboratory PSG [12][13][14][15][16][17][18] have generally shown moderately positive results, but only two of these were randomized, 14,17 and there was a great deal of methodological variability. Moreover, a cost analysis for equivalent efficacy is and their distribution in three groups (test cost, patients' cost and cost for equal efficacy) compared to polysomnography costs, which were considered to be 100% of the total cost.…”

“…Our hypopnea definition from the Sleep Spanish Network 22,31 is similar (but a little less demanding) to the "alternative" definition from the American Academy of Sleep Medicine 2007, 30 and it is the same as the definition recommended by the American Academy of Sleep Medicine 2012. 37 One of the aforementioned similar studies 12 used the "alternative" definition from the American Academy of Sleep Medicine 2007, and its prevalence was close to ours (for an AHI ≥ 10, theirs was 79%, and ours was 84%); in two other papers studying single-channel nasal pressure device, measured simultaneously with in-laboratory PSG, the prevalence for AHI ≥ 5 was 94% 38 and 85%, respectively. 9,20 Furthermore, another Spanish study with a similar methodology for home respiratory polygraphy and the same hypopnea definition found an OSA prevalence of 90%.…”

Obstructive Sleep Apnea, Health-Related Factors, and Long Distance Heavy Vehicle Crashes in Western Australia: A Case Control Study

“…In detecting severe OSA, reported sensitivity is 0.80-0.91 and specificity 0.75-0.89 at an AHI threshold of 30. 13 It should be noted that the measure of sleep time is based on the length of recording only. Participants are asked to press a button on the recorder to turn it on and off, or it automatically turns off after 8 hours.…”

“…This device is a validated nasal pressure transducer that noninvasively measures an individual's airflow during sleep. Wong et al 13 previously validated the diagnostic accuracy of Flow Wizard (used at home) for correctly identifying OSA compared with polysomnography administered under full laboratory conditions. The flow monitor device was demonstrated to have good accuracy in detecting the presence of OSA, with an area under the curve (AUC) of 0.96, and at its apnea hypopnea index (AHI) threshold of 18; the sensitivity was 0.85-0.92, and specificity 0.81-0.86.…”