Clinical trial NCT03567317: Weight Gain After CPAP Treatment in Patients With Obstructive Sleep Apnea
Official title: Mechanisms of Weight Gain During CPAP Treatment in Patients With Obstructive Sleep Apnea
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Obstructive Sleep Apnea
Keywords: CPAP
Weight Gain
obstructive sleep apnea
Lead sponsor: University of Sao Paulo General Hospital
Sponsor class: OTHER
First posted: 2018-06-25
Enrollment: 22
Sex: ALL
Minimum age (years): 50
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: SUPPORTIVE_CARE

Brief summary: The purpose of this trial is to investigate the mechanisms leading to weight gain during CPAP treatment for obstructive sleep apnea (OSA).

Detailed description: Obesity and obstructive sleep apnea share a bidirectional relationship. While obesity is a major risk factor for OSA, OSA may contribute to weight gain. Recent evidence suggests that OSA treatment is associated with weight gain. The mechanisms involved in weight gain after OSA treatment are not known. The purpose of this study is to determine the mechanisms of weight gain during CPAP treatment for severe OSA leads. The investigators hypothesis is that CPAP leads to a decrease in energy expenditure and prevents the elimination of extracellular fluid that is accumulated during the day. In order to test this hypothesis, 20 patients with severe OSA aged between 50 and 80 years old, under regular treatment with CPAP, will be invited to participate. Using a cross-over design, the investigators will perform bioelectric impedance 5 times over 24 hours in order to assess the circadian effect of fluid accumulation in two different conditions: during CPAP treatment and 7 days after CPAP withdrawal. A full polysomnography will be performed during CPAP withdrawal to confirm severe OSA and during CPAP treatment to confirm adequate control of respiratory events. In addition, basal metabolic rate, hematocrit, serum BNP, urinary sodium, creatinine and osmolality will be determined in the morning during the CPAP and CPAP withdrawal periods.

Eligibility criteria: Inclusion Criteria:

* Patients with a diagnosis of severe OSA (AHI\>30 events/h)
* 50 and 80 years old
* regular treatment with CPAP with an average daily use of \>4hours

Exclusion Criteria:

* congestive heart failure
* renal insufficiency
* hepatic failure
* urinary incontinency
* diuretic therapy

Primary outcomes:
measure: Extracellular fluid volume
timeFrame: Seven days
Secondary outcomes:
measure: Basal metabolic rate
timeFrame: 24 hours
measure: Weight change
timeFrame: 7 days
Other outcomes:
Locations:
city: Sao Paulo
country: Brazil
facility: Sleep Laboratory, Heart Institute, Pulmonary Division, Hospital das Clínicas da Universidade de São Paulo
Study officials:
affiliation: Sleep Laboratoy, Heart Institute
name: Pedro R Genta, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Herculano S, Grad GF, Drager LF, de Albuquerque ALP, Melo CM, Lorenzi-Filho G, Genta PR. Weight Gain Induced by Continuous Positive Airway Pressure in Patients with Obstructive Sleep Apnea Is Mediated by Fluid Accumulation: A Randomized Crossover Controlled Trial. Am J Respir Crit Care Med. 2021 Jan 1;203(1):134-136. doi: 10.1164/rccm.202005-1853LE. No abstract available.