Late-breaking abstract: Factors related to apnea in bariatric surgery patients using home sleep study

INTRODUCTION: The Obstructive Sleep Apnea-Hypopnea Syndrome (OSAHS) is a risk factor for bariatric surgery. There aren´t clear risk factors to identify subpopulations at risk. OBJECTIVES: Correlate clinical data and OSAHS in candidates for obesity surgery, using home sleep study. METHODS: 53 sequential candidates for obesity surgery (BMI> 33), without diagnosis of OSAHS. It was recorded: Mallampati score (MS), neck circumference (NC), chin-sternum distance (CSD) and apnea and hypopnea index (AHI - measured by ApneaLink Plus ®). The apnea, as AHI, was classified as: absent (<5), mild (5-15), moderate (16-30) and severe (> 30). RESULTS: 43 women (81%) and 10 males (19%), with medium age of 38 years. Apnea was founded in 31 (58%) patients: mild in 17 (32%), moderate in 8 (19%) and severe in 6 (11%). The greater AHI was 115, and 4 had an AHI > 50. Of the 6 patients with severe apnea, 5 (83.33%) were male. In moderate apnea, 6 (75%) were female and in mild, 16 (94%). In severe apnea, the lowest BMI was 44. At moderate apnea, 80% were classified in grade III (BMI> 40). For MS, of the 44 patients with MS III or IV, 30 (68%) had apnea; , 4 (25%) of 20 patients with MS IV had severe sleep apnea and 6 (30%) had no apnea. For NC, 100% of patients with severe apnea had CC> 40, whereas only 41% of patients with mild apnea had this feature. The CSD had no correlation with AHI. The NC/CSD ratio ≥2.5 identified 77% (17/25) of OSAHS patients and 71% (10/14) of patients with moderate OSAHS. CONCLUSIONS: Positive correlation with male gender and BMI> 44 was found. NC> 40 and the NC/CSD ratio > 2.5 ratio was associated with moderate or severe OSAHS. The portable monitoring was a reliable tool for this screening.