Sleep Apnea and Periodic Breathing

NCT ID: NCT00936273

Last Updated: 2009-07-10

Basic Information

• Recruitment Status: UNKNOWN
• Total Enrollment: 50 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2009-06-30

Brief Summary

The purpose of this study is to determine the double loop index (DLI) threshold with optimal sensitivity and specificity. The investigators hypothesize that the DLI gives a better reflection of the pathophysiology of the disease than the apnea-hypopnea-index (AHI).

Detailed Description

Sleep apnea syndrome (SAS) is characterized by repetitive events of apnea and hypopnea. These events are often part of a periodic breathing pattern, in which relative hyperventilation is followed by apnea or hypopnea.

Recently the investigators described the 'double-loop gain' of the respiratory control system as a measure of periodic breathing. This is a frequency-dependent variable which describes 1) the tendency of the respiratory system to oscillate at a given frequency and 2) the degree to which the relation between oscillations in ventilation and oscillations in arterial blood gas values is linear. The underlying hypothesis is that periodic breathing results from negative feedback regulation of arterial O2 and CO2 pressure through the chemoreflexes. The double-loop gain describes the gain in the negative feedback loop under the assumption that accidental changes occur in both ventilation and arterial blood gas pressures. A simple version of the double-loop gain is derived from nasal pressure changes and arterial O2 saturation. From all-night recordings, the 'double-loop index' (DLI) can be derived, which is determined by the time during which the double-loop gain exceeds a given threshold.

Currently, the presence of sleep-apnea is determined by the apnea-hypopnea index (AHI), using in-hospital sleep recording. With a growing number of referrals, waiting lists for sleep registration are emerging. Screening for SAS using home-measurement of nasal pressure and SaO2 seems to be a good alternative. The investigators hypothesize that the DLI derived from these signals gives a better reflection of the pathophysiology of the disease than the AHI. As a result, the investigators expect that the DLI improves the distinction between healthy and diseased subjects in comparison to the simple counting of apneas and hypopneas. This is reflected in a higher area under the ROC curve, which describes the sensitivity and specificity of the test.

Conditions

Sleep Apnea Syndrome

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: CROSS_SECTIONAL

Study Groups

Suspected sleep apnea syndrome

Outpatients with suspected sleep apnea syndrome, age \> 18 year

No interventions assigned to this group

Eligibility Criteria

Inclusion Criteria

• Suspected sleep apnea syndrome
• > 18 yr
• Outpatient
• Able and willing to use the necessary equipment for registration of nasal pressure and O2 saturation at home

Exclusion Criteria

• hospitalized patients
• < 18 yr
• Not able to use the necessary equipment

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Medical Center Alkmaar

OTHER

Sponsor Role: lead

Responsible Party

Medical Center Alkmaar

Principal Investigators

J.G. van den Aardweg, dr

Role: STUDY_DIRECTOR

Medical Center Alkmaar

Locations

Medical Center Alkmaar

Alkmaar, Wilhelminalaan 12, Netherlands

Site Status: RECRUITING

Countries

Netherlands

Central Contacts

J.G. van den Aardweg, Dr.

Role: CONTACT

j.g.vanden.aardweg@mca.nl

+3172-5482750

Facility Contacts

J.G. van den Aardweg, dr.

Role: primary

j.g.vanden.aardweg@mca.nl

+3172-5482750

Other Identifiers

Double loop gain MCA 2009

Identifier Type: -

Identifier Source: org_study_id