<p>A comparison between auto-scored apnea-hypopnea index and oxygen desaturation index in the characterization of positional obstructive sleep apnea</p>

Abstract

Objective: Evaluate the concordance between overall and positional oxygen desaturation indices (ODI) and apnea-hypopnea indices (AHI) according to two different definitions for positional obstructive sleep apnea (POSA). Methods: A total of 184 in-home polysomnograms were edited to simulate Level III home sleep apnea tests (HSAT) with the auto-scored AHI and ODI based on recording time. POSA was determined using 132 records with an AHI≥5 and at least 20 mins of recording time in both supine and non-supine positions. POSA was defined independently for the AHI and ODI based on ratios of overall/non-supine event/h ≥1.4 (O/NS) and supine/non-supine event/h≥2.0 (S/NS). Results: Correlation between the AHI and ODI was 0.97 overall, 0.94 for supine, and 0.96 for non-supine recording times (all p<0.001). For most records, differences between the AHI and ODI were small, with only 14% of the records having a AHI-ODI difference exceeding >5/hr, and 6% exceeding >10 events/hr. The positive and negative percent agreements were uniformly good to excellent across varying clinical POSA cutoffs; percent agreements (positive, negative) were: AHI≥5=0.99, 0.78; AHI≥10=0.96, 0.89; and AHI≥15=0.96, 0.89. Cohen's Kappa scores also showed substantial agreement for overall as well as supine and non-supine positions across varying clinical cutoffs of the AHI. Frequency of POSA was reproducibly uniform between 59% and 61% for both POSA criteria. When the O/NS and S/NS definitions conflicted in POSA characterization, O/NS was superior for identifying patients who might exhibit a greater response to supine restriction positional therapy. Conclusions: Auto-scored positional oximetry is a clinically viable alternative to an autoscored Level III HSAT AHI in the characterization of POSA based on a 3% desaturation.

Prediction of obstructive sleep apnea: comparative performance of three screening instruments on the apnea-hypopnea index and the oxygen desaturation index

“…Nocturnal oxygen desaturations are the result of apneas and are important in the pathogenesis and development of complications of OSA [23]. The arterial oxygen desaturation index (ODI) has therefore been proposed as an alternative for the AHI in grading PSG data and classifying OSA severity [23][24][25][26]. The ODI might be more relevant due to the higher reproducibility in the clinical setting [3,[19][20][21].…”

Validation of Oximetry for Diagnosing Obstructive Sleep Apnea in a Clinical Setting

“…Previous studies compared AHI and ODI from the same recordings, with correlation coefficients reported to range between 0.745 and 0.97 [ 14 , 15 , 16 , 17 , 18 , 19 ]. Some studies compared simultaneously performed oximetry and PSG, with correlation coefficients reported to be 0.617–0.95 [ 20 , 21 ], while others independently performed oximetry and PSG [ 23 , 24 ], with correlation coefficients of 0.6 and 0.62.…”

“…First, the oximetry ODI was not measured simultaneously with PSG/OCST. Comparisons of ODI and AHI/REI from the same recordings showed the best correlation [ 14 , 15 , 16 , 17 , 18 , 19 ] ( Figure 5 ), followed by simultaneous recording by different devices [ 20 , 21 , 25 ]. The correlation was worst when comparing ODI and AHI/REI from different devices on different nights [ 23 , 24 ] ( Figure 2 a and Figure 6 ).…”

“…These variations may come, in part, from different study designs. Some studies have compared oximetry data obtained as a part of PSG recordings to apnea events analyzed from the same PSG recordings [ 14 , 15 , 16 , 17 , 18 , 19 ]. Others have compared oximetry data with data from simultaneous PSG [ 20 , 21 , 22 ].…”

The severity of obstructive sleep apnoea does not influence ambient IGF‐I levels

“…Similarly, the ODI assesses the number of times per hour the oxygen SaO 2 levels drop below baseline by >4%. AHI and ODI scores have been shown to correlate highly in individuals with OSA 21 . Mild, moderate and severe OSA are defined by an AHI/ODI of >5–14.9, 15–29.9 and >30, respectively 1 .…”