BACKGROUND: Since the clinical presentation of obstructive sleep apnea syndrome 
(OSAS) shares common features with major depressive (MDE), the screening of OSAS 
is challenging in this population. The aim of this study was to assess the 
effectiveness of the NoSAS score in predicting the presence of OSAS among 
participants with current MDE and to compare it with the performance of existing 
screening tools.
METHODS: A random sample of the population-based cohort CoLaus (Lausanne, 
Switzerland) underwent a psychiatric evaluation (PsyCoLaus) and a complete 
polysomnography at home (HypnoLaus). The effectiveness of the NoSAS score in 
detecting the risk of significant OSAS among current MDE participants was 
assessed and compared with STOP-BANG and Berlin scores.
RESULTS: Among the 1761 subjects (58,75 ± 11y.o.; 47,8%men) who underwent 
polysomnography, significant OSAS was present in 24.0% with and 26.1% without 
current MDE. Using a threshold of ≥ 8 points, the NoSAS score identified OSAS in 
MDE participants with a sensitivity of 0.79, a specificity of 0.66, a negative 
predictive value of 0.91, and a positive predictive value of 0.41. The area 
under the ROC curve was 0.72 for NoSAS, 0.66 for STOP-BANG and 0.69 for the 
Berlin score (NS).
LIMITATIONS: Only 44% of the PsyCoLaus participants had a polysomnography. The 
studied population was mainly of Caucasian ancestry and above 40 years of age.
CONCLUSIONS: This is the first study assessing the performance of screening 
tools for OSAS in MDE. The NoSAS score is a simple and efficient screening tool 
for OSAS in this population, and may be a helpful instrument for clinicians.