CPAP in SAHS Patients With Hypertension

Study objective: To assess the nocturnal changes in mechanosensitivity and chemosensitivity in hypertensive sleep apnea-hypopnea syndrome (SAHS) patients and in SAHS patients with isolated nocturnal hypertension. To value the continuous positive airway pressure (CPAP) effect on these parameters.

Design: Controlled cross-over longitudinal study. Settings: Madrid metropolitan area. Patients: Day-night sustained hypertensive and isolated nocturnal hypertensive patients with SAHS without previous treatment. At least 30 patients are needed.

Interventions: Patients will allocate in each treatment arm (CPAP vs. sham CPAP) during three months. Explorations will perform before and immediately after sleep at 0-, 3-, and 6-months of trial.

Measurements: 24-h urinary catecholamine, local vascular factors, angiotensin and aldosterone levels. Diaphragmatic tension-time index, metabolic rate, hypoxic withdrawal test, and ventilatory and inspiratory neural drive responses to progressive isocapnic hypoxia.