Sleep Disordered Breathing, Obesity and Pregnancy Study (SOAP) (SOAP)

February 27, 2023 updated by: Francesca Facco, MD
The purpose of this study is to better understand how sleep apnea, a common sleep disorder in which a person has one or more pauses in breathing or shallow breaths while sleeping, may affect pregnancy and to determine the effect of Continuous Positive Airway Pressure (CPAP), a treatment that uses mild air pressure to keep the airways open during sleep, for pregnant women with sleep apnea.

Study Overview

Detailed Description

Emerging data support a link between sleep disordered breathing (SDB) and adverse pregnancy outcomes, particularly preeclampsia. Furthermore, SDB, which is characterized by intermittent nocturnal hypoxia-reoxygenation as well as sleep disruption, results in endothelial dysfunction and metabolic dysregulation, the same biological pathways that have been associated with adverse pregnancy outcomes. Obesity is a well-known risk factor for both adverse pregnancy outcomes and SDB, and has been associated with the same aforementioned biological aberrations. Therefore, obesity complicates the definition of a causal relationship between SDB and pregnancy outcomes. While some classic cardiovascular risk factors (prehypertension) are certainly relevant in pregnancy, there are also well-established risk factors that are unique to pregnancy (uterine vascular stiffness, placental angiogenic factors). The interplay between SDB, obesity and these unique cardiovascular risk factors remains undefined, and this proposal aims to address this knowledge gap. Without this data, our ability to understand how we can mitigate these risks through the use of therapeutic interventions for SDB, such as CPAP (continuous positive airway pressure), is compromised. To further address this knowledge gap, we will make use of the placenta's ability to accumulate evidence of damage over time and provide a record of maternal vascular health throughout gestation. Numerous placental lesions deriving from maternal vascular disease have been identified and can be readily detected on placental pathology. These lesions can provide a measure of the severity of hypoxic stress experienced by the fetus during gestation.

The investigators' central hypothesis is that SDB is an effect modifier that increases maternal cardiovascular risk and placental hypoxic injury in obese pregnant women, and that CPAP treatment during pregnancy will result in an improved cardiovascular risk and placental profile. To test this hypothesis the investigaotrs will identify a cohort of obese women both with and without SDB. The investigators will examine SDB's impact on maternal vascular stiffness (uterine artery Doppler), angiogenesis (pregnancy specific angiogenic factors e.g., sFLT-1) and metabolism (insulin resistance) across pregnancy (Aim 1). The investigators will perform a randomized controlled trial of autotitrating- CPAP verses sham-CPAP in pregnancy to examine the impact of CPAP treatment during pregnancy on cardiovascular risk (Aim 2) and will explore the interplay between SDB, CPAP and evidence of maternal vascular disease and chronic fetal hypoxia by evaluating the placental profile of obese women with and without SDB (Aim 3).

Study Type

Interventional

Enrollment (Actual)

242

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

    • Pennsylvania
      • Pittsburgh, Pennsylvania, United States, 15213
        • Magee-Womens Hospital of the UPMC

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 and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

Female

Description

Inclusion Criteria:

  • women between 14 0/7 and 20 6/7 weeks gestation at the time of their initial PSG assessment.
  • Pregnancy and current BMI >=30
  • Self-reported frequent snoring (>=3x/week over past month) or self-reported non-snorer.

Exclusion Criteria:

  • diagnosis of pregestational diabetes.
  • self-report a history of sleep apena and who are using or were receommended by a physican to use a PAP device already
  • twins

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: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
No Intervention: Obese, SDB negative
No intervention, observational comparison group
Active Comparator: Obese, SDB postive, CPAP
Therapeutic CPAP
CPAP is a device that has a mask worn over the nose that is attached to a device that provides positive airway pressure. CPAP is worn while sleeping, it splints open the airway and prevents apneas (cessation of breathing) and hypopneas (reduced airflow while breathing).
Other Names:
  • Continuous Positive Airway Pressure
Sham Comparator: Obese, SDB postive, sham-CPAP
Sham (non-therapeutic) CPAP
Other: Obese, SDB postive, sleep hygiene
Sleep hygiene information and local sleep resources
Information about sleep apnea and healthy sleep. Information about local sleep resources

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Uterine Artery Doppler Mean Pulsatility Index -by Ultrasound
Time Frame: early pregnancy (14-16 weeks gestation)
The uterine artery was located using color doppler imaging by placing the ultrasound probe in the right or left iliac fossa in the sagittal plane. The uterine artery was then identified where it crosses the external iliac artery. Doppler waveform was obtained using a sampling gate encompassing the width of the main uterine artery at an angle of insonation of <30 degrees if possible. The PI was calculated using the formula: maximum-minimum velocity/mean velocity.
early pregnancy (14-16 weeks gestation)
Soluble FMS-like Tyrosine Kinase 1 (sFlt-1)/ Placental Growth Factor (PlGF) Ratio-blood Measurement
Time Frame: early pregnancy (14-16 weeks gestation)
sFlt-1 is a splice variant of vascular endothelial growth receptor (VEGF) with antiangiogenic properties that is upregulated in preeclampsia. PlGF is an angiogenic cytokine that is highly expressed in the placenta. Low levels have been associated with preeclampsia.
early pregnancy (14-16 weeks gestation)
Homeostasis Model Assessment of Insulin Resistance (HOMA-IR)-Blood Measurement of Glucose and Insulin
Time Frame: early pregnancy (14-16 weeks gestation)
Insulin resistance was calculated using the homeostatic model assessment for insulin resistance (HOMA-IR, fasting insulin (µU/mL) x fasting glucose (mmol/L) /22.5)
early pregnancy (14-16 weeks gestation)
Uterine Artery Doppler Mean Pulsatility Index -by Ultrasound
Time Frame: late pregnancy (28-32 weeks gestation)
The uterine artery was located using color doppler imaging by placing the ultrasound probe in the right or left iliac fossa in the sagittal plane. The uterine artery was then identified where it crosses the external iliac artery. Doppler waveform was obtained using a sampling gate encompassing the width of the main uterine artery at an angle of insonation of <30 degrees if possible. The PI was calculated using the formula: maximum-minimum velocity/mean velocity.
late pregnancy (28-32 weeks gestation)
Soluble FMS-like Tyrosine Kinase 1 (sFlt-1)/ Placental Growth Factor (PlGF) Ratio-blood Measurement
Time Frame: late pregnancy (28-32 weeks gestation)
sFlt-1 is a splice variant of vascular endothelial growth receptor (VEGF) with antiangiogenic properties that is upregulated in preeclampsia. PlGF is an angiogenic cytokine that is highly expressed in the placenta. Low levels have been associated with preeclampsia.
late pregnancy (28-32 weeks gestation)
Homeostasis Model Assessment of Insulin Resistance (HOMA-IR)-Blood Measurement of Glucose and Insulin
Time Frame: late pregnancy (28-32 weeks gestation)
Insulin resistance was calculated using the homeostatic model assessment for insulin resistance (HOMA-IR, fasting insulin (µU/mL) x fasting glucose (mmol/L) /22.5)
late pregnancy (28-32 weeks gestation)

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Placental Histology and Immunohistochemistry
Time Frame: After delivery (expected 37-40 weeks gestation)
placental histology and immunohistochemistry
After delivery (expected 37-40 weeks gestation)

Other Outcome Measures

Outcome Measure
Measure Description
Time Frame
Mean Arterial Blood Pressure (mmHg) Angiogenic Domain
Time Frame: early pregnancy (14-16 weeks gestation)
early pregnancy (14-16 weeks gestation)
Pregnancy Outcome Data
Time Frame: At time of delivery (expected 37-40 weeks gestation)
Preeclampsia, Gestational diabetes, Gestational age at delivery, Indication for delivery, Birthweight, Cord gases
At time of delivery (expected 37-40 weeks gestation)
Mean Arterial Blood Pressure (mmHg) Angiogenic Domain
Time Frame: late pregnancy (28-32 weeks gestation)
late pregnancy (28-32 weeks gestation)
Soluble Endoglin (sEng ,pg/mL)-Blood Measurement
Time Frame: early pregnancy (14-16 weeks gestation)
Endoglin is a coreceptor for transforming growth factor beta-1 and beta-3 expressed on syncytiotrophoblasts
early pregnancy (14-16 weeks gestation)
Soluble Endoglin (sEng , pg/mL)-Blood Measurement
Time Frame: late pregnancy (28-32 weeks gestation)
Endoglin is a coreceptor for transforming growth factor beta-1 and beta-3 expressed on syncytiotrophoblasts
late pregnancy (28-32 weeks gestation)

Collaborators and Investigators

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

Investigators

  • Principal Investigator: Francesca Facco, MD, University of Pittsburgh

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.

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

September 1, 2014

Primary Completion (Actual)

December 1, 2021

Study Completion (Actual)

February 1, 2022

Study Registration Dates

First Submitted

February 18, 2014

First Submitted That Met QC Criteria

March 11, 2014

First Posted (Estimate)

March 13, 2014

Study Record Updates

Last Update Posted (Actual)

March 22, 2023

Last Update Submitted That Met QC Criteria

February 27, 2023

Last Verified

February 1, 2023

More Information

Terms related to this study

Other Study ID Numbers

  • PRO13080159
  • R01HL120354 (U.S. NIH Grant/Contract)
  • K12HD043441 (U.S. NIH Grant/Contract)

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.

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