Rethinking neck circumference in STOP

The STOP-BANG questionnaire is a simple screening tool for obstructive sleep apnoea (OSA) which has been validated for use in Asian populations. The original cut-off values for neck circumference were defined based on Caucasian populations. This study aims to validate the neck circumference component of the STOP-BANG score in Asians. A retrospective analysis of all patients suspected of having OSA who underwent a diagnostic polysomnography at a tertiary sleep centre in Singapore over the course of 1 year was conducted. Neck circumference was measured and correlated to the presence of OSA. A receiver operating curve was performed to obtain the optimal cut-off value for screening OSA in Asian patients. 591 Asian subjects with OSA were analysed. The optimal neck circumference predictive for OSA was found to be 39 cm in males and 35 cm in females, with a sensitivity of 83.4% and 84.6% respectively. The existing STOP-BANG cut-off of 40 cm had 71% and 32% sensitivity in Asian males and females, respectively. The STOP-BANG cut-off value for neck circumference for screening for sleep apnoea in Asian males can be maintained at 40 cm, but the neck circumference value used for screening Asian females should be lowered to 35 cm