THE VALUE OF ONE-HOUR DAYTIME SLEEP RECORDING IN THE DIAGNOSIS OF THESLEEP-APNEA SYNDROME

In this study we investigated whether the diagnosis of sleep apnoea sy ndrome (SAS), based on night-time polysomnography (NPSG), can be predi cted or excluded by a one-hour daytime polysomnography (DPSG). The res ults of 306 NPSGs were compared with DPSGs, which were performed the d ay before. Treated patients were excluded. In the 89 patients with SAS (Apnoea index (AI) greater-than-or-equal-to 5) 59 showed apnoeas duri ng the DPSG and 30 did not. In the 217 without SAS 25 showed apnoeas d uring DPSG and 192 did not. Sensitivity for detecting SAS was 66%, the specificity was 88%, the positive predictive value (PPV) 70% and the negative predictive value (NPV) 86%. For relevant SAS (AI greater-than -or-equal-to 10) the NPV would be 95%. We conclude that the one-hour D PSG is not sufficient for diagnosing or excluding SAS with certainty. It can be used to make the presence of relevant SAS unlikely.