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Comparing Two Sleep Apnea Machines Before and After Bariatric Surgery in Obesity

Compares an auto-adjusting airway pressure machine with a fixed one in adults with obesity.

Key facts

Who runs it
Hospital Universitario Ramon y Cajal
Where
Madrid, SpainSee the site
Trial code
Registry title
Effect of CPAP Versus APAP in Patients With Obesity Undergoing Bariatric Surgery Protocol
Status
Not yet recruiting
People taking part
104 people, planned
Started
15 Sept 2025
Expected to end
15 Sept 2028
Type of study
Interventional, 2 groupsOne group gets an existing treatment, for comparison.
Treatments tested
  • In the intervention group, patients will be treated with auto-adjusting APAP, providing variable pressures throughout the sleep hours.
  • CPAP
Record updated
23 July 2025

Who can take part

AI summary

From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.

The trial is looking for adults with moderate or severe obstructive sleep apnea who are on the waiting list for weight-loss (bariatric) surgery and need breathing-mask therapy.

Age
18 to 80 years
Sex
All sexes can join.
Disease stage
Moderate or severe sleep apnea (Apnea-Hypopnea Index above 15) needing treatment, and approved for bariatric surgery (BMI 35 or higher, or BMI 30 or higher with other health conditions).
Earlier treatment
People who had earlier surgery for sleep apnea, or who could not tolerate positive airway pressure treatment, cannot join.
Biomarker or test result
Apnea-Hypopnea Index (AHI) above 15 on a sleep test.

Main reasons for not taking part

  • Central sleep apnea or periodic breathing
  • Any active cancer
  • Severe uncontrolled psychiatric disorder, alcoholism or active drug addiction
  • Unacceptable surgical or anesthetic risk
  • Earlier sleep apnea surgery, or earlier positive airway pressure treatment that was not tolerated

The registry criteria, word for word

Show all 8 criteriaShow less

Who can take part

  • Subjects aged 18 to 80 years who meet the criteria for bariatric surgery and are on the surgical waiting list after approval by the bariatric surgery committee (BMI ≥35, or BMI ≥30 with comorbidities)
  • Diagnosis of moderate or severe sleep apnea, defined by an Apnea-Hypopnea Index (AHI) >15, requiring treatment according to protocol ("Patients with an AHI of 15 or higher will be treated with CPAP if they have hypertension, excessive daytime sleepiness, or sleep-related symptoms not explained by other causes" [17])
  • Patients must be able to read and understand the informed consent and provide signed consent

Who cannot take part

  • Patients with unacceptable surgical/anesthetic risk
  • Patients who have undergone previous surgery for OSA or who have been treated with positive airway pressure and did not tolerate it
  • Patients with severe uncontrolled psychiatric disorders, alcoholism, or active drug addiction
  • Patients with central sleep apnea or periodic breathing
  • Patients with any active neoplasm

Check if you might fit

Answer for yourself. This is not a decision: only the study team can say whether you can take part.

  • Are you between 18 and 80 years old?

Where in Spain

  • Hospital Universitario Ramón y CajalMadrid, SpainContact: Laura Pozuelo-Sánchez, NurseNo longer taking part

About the trial

What the trial wants to find out

Introduction Obstructive sleep apnea (OSA) is a common disorder in obese patients, especially those undergoing bariatric surgery. OSA is characterized by upper airway obstruction during sleep, leading to intermittent hypoxia and sleep fragmentation. Obesity and OSA are closely related conditions that can exacerbate each other. Positive airway pressure therapy is essential for managing OSA, but adherence to therapy can be challenging, particularly in patients who experience rapid physiological changes after bariatric surgery.

Read full original descriptionShow less

Objective This study aims to determine whether automatic positive airway pressure therapy (APAP) improves nightly usage hours compared to continuous positive airway pressure therapy (CPAP) in obese patients undergoing bariatric surgery. Secondary objectives include evaluating the percentage of nights with therapy use over 4 hours, reduction of the residual apnea-hypopnea index (AHI), changes in daytime sleepiness, pressure requirements, side effects, sleep-related quality of life, reduction in in-person visits, and optimization of healthcare resources.

Methodology A randomized, parallel-group, open-label, controlled clinical trial will be conducted. Adult patients eligible for bariatric surgery with a diagnosis of moderate to severe OSA (AHI > 15) requiring positive pressure therapy will be included. Participants will be randomized to receive either APAP or CPAP. Follow-up will be conducted over 12 months after surgery, with assessments at 3, 6, and 12 months. Data will be collected on treatment adherence, residual AHI, OSA symptoms, daytime sleepiness, quality of life, and treatment costs.

APAP therapy is expected to improve nightly usage hours compared to CPAP. It is also expected that APAP will show better adaptation to changing pressure needs after bariatric surgery. Data will be analyzed to evaluate the effectiveness and cost-efficiency of both therapies.

This study will provide evidence on the efficacy of APAP compared to CPAP in obese patients undergoing bariatric surgery. The results will help optimize the treatment of OSA in this population and improve patients' quality of life. Additionally, the study is expected to contribute to the optimization of healthcare resources by reducing in-person visits and repeated sleep studies.

The 2 groups in the trial

  • APAP GroupTreatment being tested

    APAP Group: They will receive treatment with AutoCPAP. The device automatically adjusts the air pressure according to the patient's needs, and usage data and respiratory events will be manually collected at each visit.

    Treatment: In the intervention group, patients will be treated with auto-adjusting APAP, providing variable pressures throughout the sleep hours.

  • CPAP groupExisting treatment, for comparison

    CPAP Group: They will receive treatment with conventional CPAP. The device will provide a fixed and constant air pressure, and follow-up will be conducted through in-person visits and titration with APAP after adherence to verify the optimal pressure. The initial CPAP pressure will be individually calculated using Hoffstein's formula based on parameters such as body mass index (BMI), neck circumference, and apnea-hypopnea index (AHI).

    Treatment: CPAP

Questions to ask the study team

  1. How often do I need to come in, and for how long each time?
  2. Are travel costs paid?
  3. Can I keep my own doctor?
  4. What happens if I want to stop?

Contact the study team: see the registry record → Contacts and Locations

Print a page for my doctor

Data and sources

Registry record
Listed on ClinicalTrials.gov.
Official title
Effect of CPAP Versus APAP in Patients With Obesity Undergoing Bariatric Surgery Protocol
Plain-language title
Comparing Two Sleep Apnea Machines Before and After Bariatric Surgery in ObesityGenerated from the registry record. The registry title is the official one.
AI summary
From the trial's eligibility criteria. Read by machine on 12 November 2026.
Fit questions
Built from NCT07001215, who can take part
Record updated
23 July 2025