Frequency of Obstructive Sleep Apnoea in patients being programmed for bariatric surgery

• Grant number: 11/18181-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2012
• End date: January 31, 2013
• Field of knowledge: Health Sciences - Medicine - Surgery
• Principal Investigator: Silke Anna Theresa Weber
• Grantee: Leandro Ortega Brandão
• Host Institution: Faculdade de Medicina (FMB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Obstructive Sleep Apnea Syndrome (OSA), is caused by partial or complete obstruction of the upper airways during sleep, associated with snoring, periods of apneas, and sleep fragmentation. An important risk factor is obesity and is the most important reversible risk factor in the physiopathology of OSA. Its incidence is estimated in 2-4 % of the general adult population but with an increase up to 60% in the obese one. In Brazil, IBGE dates (2008-2009) show a prevalence of overweight (IMC>25kg/m2) in more than 50% of the population older than 20 years. Obesity (IM 30kg/m2) is found in 12,5% of the male population and 16,9% of the female. Besides being the consensus of the American Academy of Sleep Medicine that all patients in evaluation for bariatric surgery should undergo screening for OSA, this is not a reality in all hospitals. As methods of screening, there are considered two questionnaires validated for Brazil: the Epworth Sleepiness Scale(daytime sleepiness) and the Berlin Questionnaire (chance for OSA); the objective evaluations are full-night polysomnography or cardiorespiratory monitoring with at least 6 channels (polygraphy). The Botucatu Medical School-UNESP consolidated and amplified its program of bariatric surgery, with an increasing number of patients enrolled. There is a necessity to evaluate the efficiency of the screening methods for identifying OSA as a co-morbidity. Aim: the aim of this study is to evaluate the frequency of OSA in obese patients waiting for bariatric surgery through screening methods, such as questionnaires and polygraphy. Methods: the local Ethic Commission (297/2010) approved this transversal study. There will be invited adult patients, of both genders, on the waiting list for bariatric surgery as per criteria established by the Gastroenterology Surgery department. The patients will answer the questionnaires for excessive daytime sleepiness (Epworth Sleepiness scale) and the risk for OSA (Berlin Questionnaire). All will realize nocturnal polygraphy and there will be obtained Apnoe-Hhypopnoe -Index (AHI), Apnoe-Index (AI), hypopnoea-Index(HI), Obstructive -Apnoe-Index (OAI), Central Apnoe-Index (CAI), Oxygen Desaturation Index (ODI), mean and minimum oxygen saturation. The data will be described individually and described the chance of the studied population having OSA. The results of the questionnaires and the polygraphy will be correlated (Spearman´s test), adopting a significance of 5%.(AU)