Early Signs of Atherosclerosis in Obstructive Sleep Apnea: Effects of Treatment
Condition: Obstructive Sleep Apnea; Atherosclerosis
MeSH terms: Apnea; Sleep Apnea Syndromes; Sleep Apnea, Obstructive; Atherosclerosis
Study type: Interventional
Phase: Phase 4

Summary: 
      Obstructive sleep apnea (OSA) is associated with adverse cardiovascular outcomes, including
      acute myocardial infarction and stroke. Atherosclerosis is an important step for these
      events. Recent studies demonstrated the independent association between OSA and validated
      markers of atherosclerosis. However, the impact of treatment with continuous positive airway
      pressure (CPAP) on these markers is unknown.

      The purpose of this study is to determine whether CPAP therapy can reverses early signs of
      atherosclerosis in apparently healthy OSA patients.
    

Detailed description: 
      Obstructive sleep apnea (OSA) is characterized by recurrent episodes of partial or complete
      obstruction of the upper airway during sleep resulting in oxygen desaturation and arousals
      from sleep. OSA is recognized as an important public health problem, affecting 9 and 24 % of
      middle-aged females and males, respectively. There is now compelling evidence that severe OSA
      is associated with increased cardiovascular morbidity and mortality, mainly due to acute
      myocardial infarction and stroke. Moreover, the current standard treatment with application
      of continuous positive airway pressure (CPAP) during the night was associated with decreased
      non-fatal and fatal cardiovascular events.

      There are several mechanisms associated with OSA that are potentially harmful to the
      cardiovascular system, including sympathetic activation, systemic inflammation, production of
      reactive oxygen species, and endothelial dysfunction. Together, all these factors could
      contribute to atherosclerosis progression, a key mechanism involved in the genesis of
      myocardial infarction and stroke. For instance, we recently described the presence of early
      signs of atherosclerosis in otherwise healthy OSA subjects as characterized by alterations in
      validated markers of atherosclerosis, including increased arterial stiffness, evaluated by
      pulse wave velocity (PWV), as well as intima-media thickness (IMT) and carotid diameter (CD).
      All theses vascular abnormalities correlated significantly with the severity of the OSA.

      In this study, we will perform a randomized study to evaluate the impact of CPAP therapy on
      PWV, IMT and CD as well as in catecholamine and C reactive protein. We made the hypothesis
      that CPAP promotes beneficial effects on atherosclerosis, independent of the other factors,
      such as blood pressure and cholesterol levels. To this end, we only will study young OSA
      patients that were free of co-morbidities. Patients will be randomized to no treatment
      (Control) or CPAP for 4 months. Evalutations will be performed at baseline and after 4
      months.
    

Intervention name(s): Continuous positive airway pressure (CPAP)
Intervention type(s): Device
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single
Primary purpose: Treatment
Keywords: obstructive sleep apnea; arterial stiffness; atherosclerosis; CPAP; heart disease