Obstructive sleep apnea syndrome (OSAS) has been linked to resistant hypertension, but the effect of treatment of OSAS on the resistant hypertension have no been established. In a double-blind randomized clinical trial patients with resistant hypertension with at least moderate sleep apnea will be randomized to receive therapeutic CPAP or Placebo CPAP for eight weeks in an ambulatory set. The investigators want to determine any difference on hypertension control between the 2 management strategies.