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Completed

NCT Number: NCT02086448

Sleep Disordered Breathing, Obesity and Pregnancy Study (SOAP)

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.

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Key information

About this study

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).

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

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

Treatment and study plan

CPAP

Device

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-CPAP

Device

Sleep hygiene

Other

Information about sleep apnea and healthy sleep. Information about local sleep resources

Primary outcomes

  1. 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.

  2. 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.

  3. 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)

  4. 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.

  5. 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.

  6. 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)

Secondary outcomes

  1. Placental Histology and Immunohistochemistry

    Time frame: After delivery (expected 37-40 weeks gestation)

    placental histology and immunohistochemistry

Other outcomes

  1. Mean Arterial Blood Pressure (mmHg) Angiogenic Domain

    Time frame: early pregnancy (14-16 weeks gestation)

  2. 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

  3. Mean Arterial Blood Pressure (mmHg) Angiogenic Domain

    Time frame: late pregnancy (28-32 weeks gestation)

  4. 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

  5. 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

Sponsors and collaborators

Lead sponsor

Francesca Facco, MD

Other

Collaborators

  • Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
  • National Heart, Lung, and Blood Institute (NHLBI)

Registry information

Acronym: SOAP

Important dates

Study start
2014
Primary completion
2021
Study completion
2022
First posted
Mar 13, 2014
Registry last updated
Mar 22, 2023

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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