Obstructive Sleep Apnea
Conditions
Keywords
CPAP, Weight Gain, obstructive sleep apnea
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.
Interventions
DEVICECPAP withdrawal
Patients randomized to withdrawal will stop CPAP use for one week before study evaluations. Patients will also undergo a polysomnography to confirm the presence of severe OSA.
Sponsors
University of Sao Paulo General Hospital
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
SUPPORTIVE_CARE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
50 Years to 80 Years
Healthy volunteers
Yes
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Extracellular fluid volume | Seven days | Extracellular fluid volume accumulation will be assessed by bioelectrical impedance after 7 days of CPAP or CPAP withdrawal. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Basal metabolic rate | 24 hours | Basal metabolic rate will be assessed by indirect calorimetry after 7 days of CPAP or CPAP withdrawal. |
| Weight change | 7 days | Weight change during CPAP use |
Countries
Brazil
Outcome results
None listed