A Comparison of Clinical Assessment and Home Oximetry in the Diagnosis of Obstructive Sleep Apnea

Abstract

In order to determine whether measurement of arterial oxygen saturation (SaO2) could identify patients with obstructive sleep apnea (OSA), 98 consecutive patients referred for assessment of snoring and/or daytime somnolence were assessed clinically and then underwent both unsupervised oximetry in their homes and formal polysomnography. Clinical assessment identified patients with an apnea+hypopnea index (AHI) > or = 15 events per hour with a sensitivity of 79% and a specificity of 50%. Home oximetry analyzed by counting the number of arterial oxygen desaturations recorded was inferior to clinical assessment. For desaturations of 2% or more from baseline, desaturation index (DI) > or = 15 per hour identified patients with AHI > or = 15 with sensitivity 65% and specificity 74%; for 3% desaturations, sensitivity was 51% and specificity 90%; and for 4% desaturations, sensitivity was 40% and specificity 98%. From the oximetry data, the percentage of time spent at SaO2 below 90% (CT90) was also calculated. CT90 > or = 1% identified patients with AHI > or = 15 with sensitivity 93% and specificity 51%; for patients with AHI > or = 15 ultimately given nasal continuous positive airway pressure (CPAP), the sensitivity of a CT90 > or = 1% was 100%. We concluded that home oximetry with CT90 < 1% practically excludes clinically significant OSA. Conversely, home oximetry with DI > or = 15 for 4% desaturations makes OSA likely: the positive predictive value for OSA is 83% if the pretest probability of OSA is 30% and over 90% if the pretest probability is at least 50%.

Prediction of sleep‐disordered breathing by unattended overnight oximetry

“…Between 1991 and the end of 1993, we performed home oximetry as a screening test for patients suspected of OSA using the CT 90 criterion we had evaluated (Gyulay et al 1993). During this period, recordings in which CT 90 was < 1% were considered to make OSA unlikely.…”

“…Other workers Clinical diagnosis of obstructive sleep apnea (OSA) is have used an index of saturation variability , inaccurate (Crocker et al 1990;Gyulay et al 1993) and but its evaluation has not been repeated. In order to confirm therefore some form of monitoring procedure is generally the results of earlier studies with a larger sample and to compare required to make or exclude the diagnosis.…”

“…We have previously oximetry and laboratory polysomnography. In order to reported (Gyulay et al 1993) that unattended pulse oximetry determine whether night-to-night variation in the severity of had sensitivity greater than 90% for the diagnosis of OSA.…”

Oxygen saturation regularity analysis in the diagnosis of obstructive sleep apnea

“…and 2%/h or more (ODI2) from baseline. Baseline was set initially as the mean level in the first 3 min of recording [16]. Typical recordings of SaO 2 patterns comparing non-OSA and OSA patients are shown in Fig.…”

Obstructive Sleep Apnea: Unjustified Diagnostic Challenges

“…This has a sensitivity of 41% to 65% and specificity of 97% to 100%, depending on desaturation values defined as abnormal. [19][20][21] The sensitivity and specificity of identifying significant obstructive sleep apnea was 65% and 74%, respectively, 21 when a criterion of a 2% desaturation from baseline was used.…”