Validation of a portable monitoring system for the diagnosis of obstructive sleep apnea syndrome.

STUDY OBJECTIVE: To evaluate if a portable monitor could accurately measure the apnea-hypopnea index (AHI) in patients with a suspicion of obstructive sleep apnea (OSA). DESIGN: Prospective and randomized. SETTING: Sleep laboratory. PARTICIPANTS: 80 participants: 70 patients with clinical OSA suspicion and 10 subjects without suspicion of OSA. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: Three-order randomized evaluations were performed: (1) STD (Stardust II) used at the participants' home (STD home), (2) STD used simultaneously with PSG in the sleep lab (STD+PSG lab), and (3) PSG performed without the STD (PSG lab). Four AHI values were generated and analyzed: (a) STD home; (b) STD from STD+PSG lab; (c) PSG from STD+PSG (named PSG+STD lab); and (d) PSG lab. Two technicians, blinded to study details, performed the analyses of all evaluations. There was a strong correlation between AHI from the STD and PSG recordings for all 4 AHI values (all correlations above 0.87). Sensitivity, specificity, and positive and negative predictive values at AHI cut-off values of 5, 15, and 30 events/hour were calculated. AHI values from the PSG lab and PSG+STD lab were compared to STD home and STD+PSG lab and showed the best results when STD and PSG were performed simultaneously. In all analyses, the area under ROC curve was at least 0.90. With multiple comparisons, diagnostic agreement was between 91% and 75%. The Bland Altman analyses showed strong agreement between AHI values from the STD and PSG recordings, especially when comparing the AHI from simultaneous STD and PSG recordings. CONCLUSION: These data suggest that the STD is accurate in confirming the diagnosis of OSA where there is a suspicion of the disorder. Better agreement occurred during simultaneous recordings.

An orientation session improves objective sleep quality and mask acceptance during positive airway pressure titration.

The aim of this study was to determine whether an orientation session led by a polysomnography (PSG) technician during the night of positive airway pressure (PAP) titration can improve objective sleep quality and acceptance of nasal mask in patients referred to a sleep laboratory. Consecutive patients (n = 1,481), referred for PAP titration during PSG, were retrospectively evaluated. Patients were distributed in two groups: the control group, patients referred for PAP titration (n = 699) who did not undertake an orientation session led by a PSG technician, and the oriented group, patients referred to PAP titration (n = 782) who followed the orientation session. Demographic data were similar (p > 0.05) between groups (control vs oriented) for: male/female proportion (76:24 vs 75:25%), age (mean +/- SD; 53 +/- 12 vs 52 +/- 12 years), Epworth Sleepiness Scale score (12 +/- 6 vs 12 +/- 6), and body mass index (31 +/- 6 vs 31 +/- 6 kg/m(2)). PSG data were different (p < 0.05) between the groups for: total sleep time (312 +/- 81 vs 326 +/- 85 min), sleep efficiency (74 +/- 17 vs 77 +/- 14%), sleep latency (22 +/- 24 vs 18 +/- 29 min), S1 (8 +/- 8 vs 6 +/- 5%), S3 4 (19 +/- 11 vs 21 +/- 13%), rapid eye movement sleep (17 +/- 9 vs 18 +/- 9%), and wake after sleep onset (106 +/- 68 vs 93 +/- 58 min). After the orientation session, the number of patients who did not accept nasal mask during PSG recording was higher in the control group than the oriented group (80 vs 44; p = 0.001). An orientation session led by a PSG technician can improve objective sleep quality and nasal mask acceptance during the night of PAP titration. Such an addition to PAP titration could be an efficient intervention to improve PAP compliance.