Sensitivity of a sequential model based on a questionnaire (STOP-Bang vs Dixon) and nocturnal pulse oximetry for screening obstructive sleep apnea in patients with morbid obesity candidates for bariatric surgery

Abstract

Introduction

Obstructive sleep apnea (OSA) has a high incidence in patients with morbid obesity (MO) who are candidates for bariatric surgery (BS). Adequate screening would decrease the number of respiratory polygraphies (RPs).

Objective

To analyze the value of a sequential model consisting of a questionnaire (modified Dixon (DXM VS STOP-Bang) and nocturnal pulse oximetry (POX) in patients who were candidates for BS.

Methods

A prospective study was conducted from July 1, 2014 to July 1, 2015 on candidates for BS, excluding those who have already undergone RP. Variables: questionnaires (Epworth, STOP-Bang, and DXM), anthropometric measurements, RP, and blood and gas tests. The sample was divided into patients with no or mild OSA (no OSA) and those with moderate to severe OSA (AHI > 15).

Results

A total of 70 patients were analyzed, 46 (65.7%) of them females. Moderate to severe OSA was diagnosed in 26 (37.1%) patients. STOP-Bang and DXM were compared using ROC curves, and greater area under the curve (AUC) was found for the latter (0.873(0.74−0.930) vs 0.781(0.673−0.888)). STOP-Bang had greater sensitivity, 100%, as compared to 73.1% for DXM. ODI3% showed greater diagnostic yield (AUC = 0.982 (0.970-1). Use of the sequential model with STOP-Bang>3, DXM > 5, and DXM > 3 would have avoided 41 (58.5%), 50 (71.4%), and 41 (58.5%) RPs and 0, 7 (10%), and 0 false negatives respectively.

Conclusion

Use of a sequential model based on the STOP-Bang and nocturnal POX is a useful tool for screening OSA in patients with MO candidates for BS, decreasing the number of RPs.

Resumen

Introducción

La apnea obstructiva del sueño (AOS) tiene una elevada incidencia en obesos móribos (OM) candidatos a cirugía bariátrica (CB). Un screening adecuado reduciría el número de poligrafías (PR).

Objetivo

Analizar la utilidad de un modelo secuencial con un cuestionario (Dixon modificado (DXM VS STOP-Bang) y pulsioximetría nocturna (POX) en pacientes candidatos a CB.

Metodología

Estudio prospectivo, desde el 1 de Julio de 2014 hasta el 1 de Julio de 2015. Se incluyeron candidatos a CB, excluyéndose aquellos que ya se habían sometido a una poligrafía. Variables: cuestionarios (Epworth, STOP-Bang y DXM), medidas antropométricas, poligrafía y analítica de sangre y gases. Se dividió la muestra entre los que no tenían AOS o era leve (No AOS) y los que tuvieron una AOS moderada - grave (IAH > 15).

Resultados

Se analizaron 70 pacientes, de los cuales 46 (65,7%) mujeres. Se diagnosticaron 26 (37,1%) de AOS moderada - grave. Comparamos STOP-Bang y DXM mediante curvas ROC con una mayor área bajo la curva (AUC) para este último (0,873(0,74 -0,930) VS 0,781(0,673-0,888)). La sensibilidad fue superior para el STOP-Bang con un 100% VS 73,1% de DXM. El IDO3% presentó mayor rentabilidad diagnóstica AUC = 0,982(0,970-1). La aplicación del modelo secuencial con STOP-Bang>3, DXM > 5 y DXM > 3 hubiese evitado 41(58,5%), 50(71,4%) y 41(58,5%) poligrafías y 0, 7(10%) y 0 falsos negativos respectivamente.

Conclusión

La aplicación de un modelo secuencial basado en el STOP-Bang y POX nocturna es una herramienta útil para el screening de AOS en OM candidatos a CB, reduciendo el número de PR.