Home-based diagnosis of obstructive sleep apnea by polysomnography type 2: accuracy, reliability, and feasibility

Despite being used in large cohort studies, role of polysomnography (PSG) type 2 is still controversy. This study was aimed to determine its accuracy, reliability, and feasibility in diagnosis of obstructive sleep apnea (OSA) compared to gold standard.

Adult patients with stable medical conditions who complained of snoring or excessive sleepiness and lived around Bangkok were recruited from a sleep clinic. All were asked to fill questionnaires and have PSG done in laboratory (in-Lab PSG) and at home (Home PSG) on separate nights within 2-4 weeks interval.

Eighty-six patients, 48 males and 38 females, were included. Mean of total sleep time, sleep efficiency, and stage R were significantly greater in Home PSG than in-Lab PSG (p<0.05). Apnea-hypopnea index (AHI) was slightly higher in Home PSG (25.7 versus 23.5, p=0.04), but with excellent reliability, intra-class correlation coefficients of 0.96 (95% CI; 0.93-0.97), and good agreements (κ=0.59-0.70) between both tests. The sensitivity, specificity, and accuracy of Home PSG at cut-off point of AHI≥5, were 0.97, 0.56, and 0.85, respectively, and at AHI≥15 were 0.95, 0.76, and 0.85, respectively. Sixty-four patients (74.4%) preferred home-PSG but four patients (4.7%) needed repeated tests due to significant data loss.

This is the first report in Asia demonstrating that home-based diagnosis of OSA by PSG type 2 was feasible performing with good reliability, high accuracy, and a low failure rate. However, further studies focusing on its cost-effectiveness are required.