SESSION TYPE: Sleep III
PRESENTED ON: Wednesday, October 24, 2012 at 02:45 PM - 04:15 PM
PURPOSE: STOP-Bang questionnaire is a sensitive but not specific screening tool to identify surgical patients with high risk of obstructive sleep apnea (OSA). It has not been validated as a screening tool for OSA in patients undergoing bariatric surgery. Nocturnal pulse oximetry measuring oxygen desaturation index ≥ 4% from baseline/hour of sleep (ODI) is a potential screening method for OSA. However, its accuracy in morbidly obese patients is unknown. We sought to determine the sensitivity and specificity of STOP-Bang questionnaire combined with ODI for screening of OSA in bariatric surgery patients.
METHODS: Patients being evaluated for bariatric surgery were asked to answer the STOP questionnaire (snoring, tiredness, observed apnea, high blood pressure) during preoperative assessment. The BMI, age, neck circumference and gender were documented. All patients underwent type Ι overnight polysomnography (PSG) prior to surgery. ODI was obtained from the PSG. An ODI ≥ 5/hr was considered elevated. Only patients with completed STOP-Bang and PSG were included.
RESULTS: A total of 55 patients were included. The mean age was 40.7 ± 12.3 years; 27% males; BMI 47.2 ± 8.8 kg/m2. We classified 49 patients (89%) as high risk based on the STOP-Bang questionnaire (≥3 positive responses). A total of 39 patients (71%) were diagnosed with OSA (AHI ≥5); 17 mild (AHI 5-14/hr), 10 moderate (AHI 15-29/hr) and 12 severe (AHI ≥30/hr). The sensitivity of the STOP-Bang questionnaire for OSA (AHI ≥5) was 92% and the specificity was 19%. With combination of STOP-Bang ≥3 and ODI ≥5/hr, the specificity for AHI ≥5 increased to 87%. The sensitivity was 85%, positive predictive value 94% and negative predictive value 70%, respectively.
CONCLUSIONS: The preliminary results of the STOP-Bang questionnaire suggest a high sensitivity to detect OSA in the bariatric population; however specificity was poor. The specificity markedly increased by combining STOP-Bang ≥3 with ODI ≥5/hr. Further evaluation of ODI with unattended oximetry is required.
CLINICAL IMPLICATIONS: The combination of STOP-Bang and other measures such as ODI may decrease the need for PSG prior to bariatric surgery.
DISCLOSURE: The following authors have nothing to disclose: Ali Khodabandeh, Julia Tassinari, Ryan Chua, Anthony McCluney, Nicole Pecquex, Katherine Hendra
No Product/Research Disclosure InformationDivision of Pulmonary, Critical Care, and Sleep Medicine, St. Elizabeth's Medical Center, Tufts University School of Medicine, Boston, MA