Central and Peripheral 24-h Blood Pressure Before and After 3 Month of CPAP Treatment in Obstructive Sleep Apnea

Central and Peripheral 24-h Blood Pressure Measurements in Patients With Chronic Renal Failure and Obstructive Sleep Apnea Before and After Treatment With CPAP

The purpose of this study is to investigate the effect of 3 months of continuous positive airway pressure (CPAP) treatment of obstructive sleep apnea (OSA) in moderate to severe cases in patients with chronic kidney disease. The effect is evaluated on blood pressure levels, particularly nocturnal blood pressure, both central and peripheral, and renal function, including the kidneys treatment of salt and water.

Hypothesis:

1. Central 24-h blood pressure measuring is a reveals fluctuations in blood pressure during the day more accurately than peripheral 24-h blood pressure measuring because the measurement is painless and does not interfere with the patient activities during the daytime or nighttime sleep.
2. Central blood pressure is elevated in patients with OSA and falls during treatment with CPAP.
3. The renal tubular function relating to the treatment of water and sodium is abnormal in patients with OSA with increased tubular absorption of water via the U-aquaporin 2 (u-AQP2) and of sodium by epithelial sodium channel (ENAC) and is normalized during treatment with CPAP.

4 Quality of life is improved during treatment with CPAP.

Approximately 30 patients with chronic kidney disease and obstructive sleep apnea in moderate to severe degree is examined with central and peripheral 24-h blood pressure monitoring, 1 night home polygraphy to determine the degree of sleep apnea, blood and urine samples to determine levels of u-AQP2, u-ENAC, plasma renin concentration (PRC), s-angiotensin II (p-angII), p-aldosterone, p-vasopressin (p-avp) and p-endothelin, before the start treatment with CPAP for sleep apnea.

After 3 month of treatment all the above described is repeated to determine effects of CPAP treatment on blood pressure levels during the day, changes i apnea hypopnea index (AHI) and the kidneys treatment of salt and water.

Inclusion Criteria:

• renal insufficiency (CKD stage III + IV), estimated glomerular filtration rate (eGFR) 15-59 ml/min/1.73 m2
• Obstructive sleep apnea, AHI> 15 (moderate to severe)
• both men and women
• 18-80 years

Exclusion Criteria:

• lack of desire to participate
• malignant disease
• Abuse of drugs or alcohol
• pregnant and lactating
• incompensated heart failure
• atrial fibrillation
• liver disease (alanine aminotransferase> 200)
• Severe chronic obstructive lung disease (Forced expiratory volume in 1 second <50% predicted)