TOPIC: Sleep Disorders TYPE: Original Investigations PURPOSE: Obstructive sleep apnea (OSA) is a common condition which leads to morbidity, especially cardiovascular events. Polysomnography (PSG) is considered the gold standard for diagnosis of OSA however has limited availability and high cost. Despite the development of various screening tools, such as the STOP-BANG Score, the Berlin Questionnaire, the Epworth Sleepiness Scale (ESS), and the NoSAS Score, these tools are validated in Caucasian populations and mainly consist of anthropometric obesity index. This differs from the OSA among Asian population which usually, appears in non-obese patients, and are caused by craniofacial abnormalities. We aimed to develop and validate a risk score in prediction of clinically significant OSA among Thai patients. METHODS: The NH-OSA score (NH-OSA), which consists of the follows; having neck circumference of 13 inches (in female) or 15 inches (in male), or greater (total of 1 point), presence of hypertension (total of 4 points), having body mass index; BMI of 23-24.9 kg/m2, 25-30 kg/m2, greater than 30 kg/m2 (Total of 3,5,7 points, respectively), presence of moderate or severe snoring (total of 9 points), and age of 40 years or greater (total of 5 points), were collected from 1,798 adult patients underwent full-night or split-night PSG in King Chulalongkorn Memorial Hospital from year 2017 to 2019. Clinical risk score was developed using multiple factor analysis and logistic regression. Patients at risk of clinically significant OSA were defined by apnea/hypopnea index (AHI) of 15 or greater. Of the enrolled, 450 patients were randomly included in the internal validation study. Moreover, the NH-OSA was externally validated at the sleep center of Bangkok Christian Hospital. RESULTS: With cutoff value at 14 points, the sensitivity, specificity, and positive likelihood ratio of NH-OSA were 82.1%, 68.7% and 2.62 respectively. The AUC was 0.75 (95%CI 0.73 – 0.78). Both internal and external validation study revealed high AUC of 0.74 (0.68-0.80), 0.75 (0.60-0.90), respectively. These were greater when compared to the STOP-BANG Score (AUC 0.68, 95% CI 0.65-0.71, p < 0.0001), the Berlin Questionnaire (AUC 0.59, 95%CI 0.56-0.62, p < 0.0001), ESS score (AUC 0.49, 95% CI 0.46-0.51, p < 0.0001), and NoSAS Score (AUC 0.69, 95% CI 0.67-0.72, p = 0.0001). CONCLUSIONS: NH-OSA has good performance in prediction of clinically significant OSA with high validity among Thai population. It could help screening patients at risks of OSA for further investigation, particularly in the resource limited area. CLINICAL IMPLICATIONS: NH-OSA is a newly developed tool, which could help screening patients at risks of OSA for further investigation DISCLOSURES: no disclosure on file for Nattapong Jaimchariyatam; No relevant relationships by Jeerath Phannajit, source=Web Response No relevant relationships by Supakorn Srichan, source=Web Response No relevant relationships by Somkanya Tungsanga, source=Web Response
Read full abstract