NoSAS score predicts cardiovascular disease in patients with obstructive sleep apnea

Abstract

Purpose: The Lausanne NoSAS (Neck circumference, Obesity, Snoring, Age, Sex) score is a new tool for the identification of high-risk patients for obstructive sleep apnea (OSA). Up to now, no study has attempted to determine the role of NoSAS score in cardiovascular morbidity of patients with OSA. We aimed to investigate the relationships between NoSAS scores and CVD and also between severity of OSA, polysomnographic parameters, and NoSAS scores in patients with OSA.

Methods: Patients with diagnosis of OSA by full-night polysomnography were recruited in the study. Based on apnea-hypopnea index (AHI) scores, the patients were categorized as OSA-negative (AHI < 5), mild OSA (5 ≤ AHI < 15), moderate OSA (15 ≤ AHI < 30), and severe OSA (AHI ≥ 30). The definition of cardiovascular diseases (CVD) included the presence of any of the diseases such as hypertension, coronary artery disease, heart failure, or arrhythmia.

Results: A total of 1514 patients including cases with 199 OSA-negative, 391 mild, 342 moderate, and 582 severe OSA were enrolled in the study. NoSAS scores were significantly different between mild, moderate, and severe OSA groups. NoSAS scores were negatively correlated with minimum oxygen saturation values and positively with AHI and ODI (oxygen desaturation index) values (P < 0.001). NoSAS scores were significantly higher in patients with CVD, diabetes mellitus, and cerebrovascular disease compared with those without (P < 0.005). NoSAS cut-off values for hypertension (14), congestive heart failure (8.5), coronary artery disease (9), cerebrovascular event (11), and diabetes mellitus (10) were also determined.

Conclusion: NoSAS scores are associated with CVD and the severity of OSA. NoSAS scores may be useful to predict CVD in patients with OSA.

Keywords: Cardiovascular disease; NoSAS score; Obstructive sleep apnea; Polysomnography; Screening.