Study of sleep, respiratory control during sleep and quality of life in morbidly obese subjects undergoing bariatric surgery.

• Register: REBEC
• Last refreshed on: 29 April 2013
• Main ID: RBR-9k9hhv
• Date of registration: 11/07/2011
• Primary sponsor: Universidade Nove de Julho - UNINOVE - Brazil
• Public title: Study of sleep, respiratory control during sleep and quality of life in morbidly obese subjects undergoing bariatric surgery.
• Scientific title: Sleep study, respiratory mechanics, chemosensitive response and quality of life in morbidly obese patients undergoing bariatric surgery: A prospective, randomized, controlled
• Target sample size: 17
• Recruitment status: recruiting
• URL: http://www.ensaiosclinicos.gov.br/rg/RBR-9k9hhv/
• Study design: Prospective, randomized, controlled trial, two arms, blind paralel study.

Countries of recruitment

Brazil

Contacts

• Name: Luis Vicente Oliveira
• Affiliation: Universidade Nove de Julho - UNINOVE

• Name: Luis Vicente Oliveira
• Affiliation: Universidade Nove de Julho - UNINOVE

Key inclusion & exclusion criteria

Inclusion criteria: Grade III morbid obesity (BMI between 40 and 55 kg/m²) or between 35 and 39 kg/m² with comorbidities;
Both gender patients aged 18 to 65 years;
Documented history of conventional weight loss attempts having proven unsuccessful over time;
Agreement to participate in the study through a signed term of informed consent.

Exclusion criteria: Any medical condition rendering surgery too risk;
Clinically significant or unstable mental health concerns;
Pregnancy, lactation or planned pregnancy within two years of potential surgical treatment;
Smokers (at least 8 weeks prior to surgery), abusive alcohol use and/or drugs use.


Age minimum: 18Y
Age maximum: 65Y
Gender: -

Health Condition(s) or Problem(s) studied

We will study subjects with morbid obesity, considered nutritional and metabolic disease, undergone bariatric surgery, for investigation of sleep disorders, especially obstructive sleep apnea.
E02.065.062
C08.618.085.852.850
C18.654.726.500
C10.886

Intervention(s)

Subjects morbid obese undergone bariatric surgery will be asked to participe in the study. All the subjects' evaluations will occur prior to the surgical intervention and 30, 90 and 360 days following the procedure. All subjects in both groups will be submitted to the following evaluation protocol. General clinical measurements will be performed include body weight (kg), height (m), calculation of body mass index (BMI) using the formula weight/height2, circumferences (cm) of the neck, waist, and hip, heart and respiratory rates, blood pressure values, Mallampati index, tonsil index , the administration of specific questionnaires for sleep apnoea and excessive daytime sleepiness and a quality of life questionnaire and standart overnight polysomnography.
The intervention group will be composed of subjects who underwent bariatric surgery and control groups by the subjects that will not be subjected to surgery due to the extensive waiting list associated with small service demand, although they are suited to the surgical procedure.

Primary Outcome(s)

Apnea/hypopnea index by standard overnight polysomnography.
Sleep study will be performed with an standard overnight polysomnography monitoring system recording EEG, EMG and EOG, thoracic and abdominal movements by strain gauges, oro-nasal airflow by thermistor, snoring, body position, heart rate by cardiotachography, and pulse oximetry. An apnea was defined as the absence of airflow for more than 10 seconds and classified as central in the absence of thoraco-abdominal movements. Hypopnea was defined as a 50% decrease of airflow and thoraco-abdominal movements with a consensual oxyhaemoglobin desaturation, and classified as central hypopnea in the absence of paradoxical movements of thorax and abdomen.

Slope of ventilatory response to carbon dioxide performed by spirometry. The rebreathing test was performed according to Read technique. Patients breathed through a mouthpiece and, after a steady state was achieved, basal ventilation was recorded for three minutes. Then patients started to breath connected to a 15 L latex balloon filled with a 7% CO2 and 93% O2 mixture for five minutes or until an end-tidal CO2 pressure PetCO2 of 70 mm Hg was reached or until exhaustion. Data were acquired by a metabolic cart (Vmax 29c, Sensor Medics, USA) and the slope of ventilatory response to carbon dioxide was obtained from the linear regression between ventilation and PetCO2. Data were adjusted by a 0.9 correction factor to correct flow readings for hyperoxic gas mixture.

Secondary Outcome(s)

Evaluation of the risk to obstructive sleep apnea through Berlin Questionn

Evaluation of diurnal sleepiness intensity by the Epworth Sleepiness Scale.

Evaluation of quality of life, weight loss percentage and changes in medical conditions through the Bariatric Analysis and Reporting Outcome System (Baros).

Maximal inspiratory pressure and maximal expiratory pressure evaluated by digital manovacuometer.

Sleep physiological variables assessed by the standart overnight polysomnography.

The measurements of waist and neck circumference at physical exam.

Thorax and abdomen cirtometry at physical exam.

Weight loss evaluated by Body mass index.

Secondary ID(s)

220506/2009

481169/2008-3

Source(s) of Monetary Support

Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (local acronym CNPq) - Brazil