Weight Loss and Obstructive Sleep Apnea

Not Applicable

Completed

• Conditions: Obstructive Sleep Apnea
• Interventions: Behavioral: Energy Restriction

• Registration Number: NCT02206126
• Lead Sponsor: Rio de Janeiro State University

Brief Summary

The purpose of this study is to evaluate the effects of moderate energy restriction on the body adiposity, severity of OSA, blood pressure, sympathetic activity, oxidative stress, inflammatory biomarkers, metabolic profile and endothelial function in obese patients with OSA.

Detailed Description

Introduction: Nutritional intervention for weight loss is one of the treatment options for obstructive sleep apnea (OSA) in patients with excess body adiposity. However, the effects of moderate energy restriction, recommended by current guidelines for the treatment of obesity, on OSA are not yet known. Objective: To evaluate the effects of moderate energy restriction on the body adiposity; severity of OSA; blood pressure; sympathetic activity; oxidative stress; inflammatory biomarkers; metabolic profile and endothelial function in obese patients with OSA. Methods: A 16-week randomized clinical trial, involving 21 subjects with obesity (grade I or II), aged 20-55 years and presenting an apnea/hipopnea index (AHI) \> 5 events/h. Participants were randomized into 2 groups: 11 in the energy restriction group (ERG) and 10 in the control group (CG). The ERG was instructed to follow an energy-restricted diet (-800 kcal/day) and the CG was advised not to change their food intake. At the beginning and at the end of the study, participants underwent evaluation of: OSA with the equipment Watch- PAT200® including the determination of the following parameters of OSA severity: AHI, minimum O2 saturation, number of O2 desaturations \>4%; body adiposity (weight, %body fat and circumferences of waist, hip and neck); blood pressure (BP); sympathetic nervous system activity (plasma levels of catecholamines); inflammatory biomarkers (c-reactive protein and adiponectin); oxidative stress (malondialdehyde); metabolism of glucose (glucose, insulin and HOMA-IR) and lipids (total cholesterol and fractions and triglycerides); and endothelial function (index of reactive hyperemia evaluated by Endo - PAT 2000® and cellular adhesion molecules). The statistical analysis was performed with the software STATA v. 10. The level of statistical significance was p \< 0.05.

Study Timeline

• Study Start: 2012-03
• Primary Completion: 2013-10
• Study Completion: 2013-10
• Study First Submitted: 2014-06-27
• Status Verified: 2014-07
• Study First Submitted QC: 2014-07-30
• Last Update Submitted: 2014-07-30
• Study First Posted: 2014-08-01
• Last Update Posted: 2014-08-01

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 21

Inclusion Criteria

• age between 20-55 years
• body mass index (BMI) ≥ 30 kg/m2 and < 40 kg/m2

Exclusion Criteria

• smoking
• Use of dietary supplements
• Use of medications that could interfere in body weight, metabolic profile and blood pressure
• Use of permanent pacemaker; use of α-adrenergic blocking agents
• Recent changes (within previous 6 months) in body weight (> 3 kg), in dietary intake and in intensity or frequency of physical exercise
• Diagnosis of diabetes mellitus, hypertension, dyslipidemia (with drug treatment) and kidney disease
• Clinical history of thyroid dysfunction, angina pectoris, peripheral vascular disease, peripheral neuropathy, heart failure, liver failure, chronic pulmonary disease, gastroesophageal reflux disease, myocardial infarction and stroke; finger deformity that prevents the proper use of the sensors that are necessary to evaluate OSA and endothelial function; and previous bilateral cervical-thoracic sympathectomy
• Pregnant or lactating women were not allowed into the study

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Energy restriction group	Energy Restriction	The energy restriction group was instructed to follow an energy-restricted diet (-800 kcal/day).

Primary Outcome Measures

Name	Time	Method
Apnea/hipopnea index	16 weeks

Secondary Outcome Measures

Name	Time	Method
Blood pressure	16 weeks
Sympathetic activity	16 weeks	Plasma levels of catecholamines
Oxidative stress	16 weeks	Serum levels of malondialdehyde
Inflammatory biomarkers	16 weeks	Circulating levels of high-sensitivity C reactive protein and adiponectin
Metabolic profile	16 weeks	Fasting plasma glucose, insulin, total cholesterol, HDL-cholesterol, LDL-cholesterol and triglycerides
Endothelial function	16 weeks	Circulating levels of cellular adhesion molecules (intercellular adhesion molecule 1 and P-selectin).; Endothelial function was also evaluated by the PAT method, using Endo-PAT 2000®.

Trial Locations

Locations (1)

Discipline of Clinical and Experimental Pathophysiology, CLINEX; 🇧🇷 Rio de Janeiro, Brazil