Influence of nCPAP on Metabolic Consequences Associated With OSAS

November 19, 2007 updated by: Federal University of São Paulo

Improvement in Hypothalamic-Pituitary-Adrenal Axis Function After Continuous Positive Airway Pressure Therapy in Obstructive Sleep Apnea Syndrome

Context: Obstructive sleep apnea syndrome (OSAS) is associated with cardiovascular morbidity. Recurrent episodes of occlusion of upper airways during sleep result in hormonal changes that may predispose to high cardiovascular risk.These risks can rapidly be reduced by effective nasal continuous positive airway pressure (nCPAP) therapy Objective: To evaluate hypothalamic pituitary adrenal axis, insulin resistance, blood pressure values and adipokines in severe obese patients with and without OSAS and to determine if continuous positive airway pressure therapy (nCPAP) influenced responses.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

Background: There is evidence that obstructive sleep apnea syndrome (OSAS) increases the risk of cardiovascular events. Sympathetic nervous system and hypothalamic-pituitary-adrenal (HPA) axis activation may be the mechanism of this relationship. We evaluate HPA axis and metabolic consequences in obese patients with and without OSAS and we determine if continuous positive airway pressure therapy (nCPAP) influenced responses.

Methods: Plasma inflammatory cytokines, insulin resistance index, 24-hour ambulatory blood pressure monitoring and overnight cortisol suppression test with 0.25 mg of dexamethasone were performed in 22 severe obese patients with OSAS and 23 obese controls. Ten patients with severe apnea were re-evaluated three months after nCPAP therapy.

Results: Body mass index, abdominal circumference, blood pressure levels and insulin resistance indexes of OSAS patients and obese controls were very similar. In OSAS patients, adiponectin (p<0.05) and salivary cortisol suppression pos DEX (p<0.05) were lower, while heart rate (p<0.05) and TNF-alpha levels (p<0.05) were higher compared with obese controls. After nCPAP therapy, patients showed a reduction in heart rate (p=0.036) and a higher cortisol suppression after dexamethasone (p=0.001) and there were no differences in insulin resistance (HOMA p=0.139), arterial blood pressure (p=0.183) and adipokines compared with baseline. Cortisol suppression was positively correlated with the improvement of apnea hypopnea index while on nCPAP therapy (r= 0.799, p=0.010).

Conclusions: Patients with OSAS present nocturnal hypercortisolism, hyperactivity of sympathetic central nervous system, a higher degree of inflammation and hypoadiponectinemia independent of the body mass index. Furthermore, hyperactivity of HPA axis and sympathetic nervous system are recovered by nCPAP.

Study Type

Interventional

Enrollment (Actual)

45

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Brazil
    • SP
      • Sao Paulo, SP, Brazil, 04023-062
        • Universidade Federal de São Paulo

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 65 years (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Aged from 18 to 65 years
  • Body mass index between 35-60 who were submitted to polysomnography

Exclusion Criteria:

  • History of smoking
  • Sleep apnea treatment
  • Cardiovascular disease
  • Malignancies tumor
  • Thyroid disorders
  • Depression
  • Subjects with known diabetes mellitus on medications
  • Chronic renal or hepatic failure
  • On hormonal replacement therapy, as well as use of medication that could potentially affect steroid hormone or cytokines secretion (alcohol, psychotropics, steroids, sympathomimetics, beta-blockers).

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Non-Randomized
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: A
10 patients with severe OSAS (Apnea Hypopnea Index of more than 30 events per hour of sleep) were treated with nCPAP for three months and all mentioned measurements above were repeated.
Procedure: nasal continuous positive airway pressure
After an average interval of three months, 10 patients with severe OSAS (AHI of more than 30 events per hour of sleep) treated with a mean nCPAP pressure of 11.2 ± 0.7 cm of H2O were reassessed and all mentioned measurements above were repeated

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
To explore the interactive mechanisms of HPA axis, sympathetic nervous system activation, inflammatory cytokines, insulin resistance and hypertension in patients with and without sleep apnea, excluding the interference of the degree of fat accumulation.
Time Frame: one day
one day

Secondary Outcome Measures

Outcome Measure
Time Frame
To evaluate low-dose dexamethasone-induced cortisol suppression and circadian rhythm of cortisol secretion in severe obese patients with sleep apnea in response to treatment with continuous positive airway pressure.
Time Frame: three months
three months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Federal University of São Paulo

Investigators

  • Principal Investigator: Gláucia Carneiro, MD, UNIFESP-EPM

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

October 1, 2004

Study Completion (Actual)

March 1, 2006

Study Registration Dates

First Submitted

February 14, 2007

First Submitted That Met QC Criteria

February 14, 2007

First Posted (Estimate)

February 15, 2007

Study Record Updates

Last Update Posted (Estimate)

November 20, 2007

Last Update Submitted That Met QC Criteria

November 19, 2007

Last Verified

November 1, 2007

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 12383

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Obstructive Sleep Apnea Syndrome

Clinical Trials on nasal continuous positive airway pressure

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Kyrgyzstan

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

3
Subscribe