Application of Neck Circumference in Four-Variable Screening Tool for Early Prediction of Obstructive Sleep Apnea in Acute Ischemic Stroke Patients

Abstract Background: The purpose of this study was to validate and pilot the use of the four-variable screening tool (4V) and modified 4V tools to identify acute ischemic stroke and transient ischemic attack (TIA) patients at high risk of obstructive sleep apnea (OSA). Methods: Two modified scales, 4V-1 (ie, using neck circumference instead body mass index, regardless of gender) and 4V-2 (ie, as above but scored differently according to gender) were designed. These tools were used in a consecutive cohort of 124 acute ischemic stroke/TIA patients, together with the 4V-1, 4V-2, 4V, as well as the STOP-BANG, the Berlin questionnaire, and the Epworth Sleepiness Scale (ESS). Objective level 2 or level 3 polysomnography was used to confirm OSA and its severity. Both questionnaires and polysomnography were completed within 1 week from symptom onset. Results: Area under the curve (AUC) of 4V was 0.807 ( P P P P  = .1556), respectively. AUC of 4V was greater than of STOP-BANG ( z  = 2.200, P  = .0220), Berlin ( z  = 2.024, P  = .0430) and ESS ( z  = 3.363, P  = .0003). AUC of modified 4V-1 and modified 4V-2 were .824 ( P P z  = 2.111, P  = .0348) and higher but not significantly so to regular 4V ( z  = 1.784, P  = .0744). Conclusions: Neck circumference scored by gender is a useful substitution to body mass index in the 4V when screening OSA at early stages of ischemic stroke/TIA patients.