Obstructive sleep apnoea (OSA) is the main secondary form associated with 
resistant hypertension (RH), but it is largely underdiagnosed and consequently 
undertreated in clinical practice. The Berlin questionnaire (BQ) is a useful 
tool among general population, but seems to not perform well among patients with 
RH. Recently, NoSAS score was validated in a large population, however, has not 
been tested in the cardiovascular scenario. Thus, we aimed to compare BQ versus 
the NoSAS score as screening tools for OSA in RH. In the present study, patients 
with confirmed diagnosis of RH were invited to perform polysomnography. OSA was 
diagnosed by an apnoea-hypopnoea index (AHI) ≥15 events/h. BQ and NoSAS were 
applied in a blinded way. We calculated the sensitivity, specificity, positive 
predictive value (PPV), negative predictive value (NPV) and area under the curve 
(AUC) of the two sleep questionnaires to detect OSA in RH. The frequency of OSA 
was 64%. The BQ presented a better sensitivity (91 vs. 72%) and higher values of 
NPV (67 vs. 54%) than NoSAS score. In contrast, the NoSAS score had higher 
specificity for excluding OSA (58 vs. 33%) and higher PPV (75 vs. 70%). Compared 
to the BQ, NoSAS score had a better AUC (0.55 vs. 0.64) but these values are in 
the fail to poor accuracy range. In conclusion, both BQ and NoSAS score had low 
accuracy for detecting OSA in RH. Considering the high frequency of OSA, 
objective sleep study may be considered in these patients.