Objective: To analyze the impact of CPAP treatment on cognitive, clinical and quality of life domains in patients over 70 years of age with mild-to-moderate OSA

Primary Outcome: Epworth scale and QSQ domains

Secondary Outcomes: Neurocognitive variables and CPAP adherence

Inclusion Criteria:

• Age equal or greater than 70 years of both sexes
• Patients with sleep study results with AHI ≥ 15 and < 30

Exclusion Criteria:

• Alternative diagnoses of other non-respiratory sleep disorders that are also cause of pathological somnolence (eg, sdr restless legs, narcolepsy, etc.)
• Don't sign informed consent
• Acute or chronic respiratory insufficiency requiring home oxygen therapy
• Patients with Obesity Hypoventilation Syndrome
• Diagnosis of neuro-psychiatric diseases with the exception of anxiety - depression or diagnosis of dementia.
• Diseases of any origin in the acute phase
• Heart failure or recent stroke (less than 3 months).
• Central SAHS (more than 50% of the registry with central apneas or Cheyne-Stokes breathing)
• Pre-treatment with CPAP
• Inability to perform the diagnostic study of sleep due to the patient's condition
• Hipersomniaincapacitante (Epworth≥18) with no known or most likely cause related to SAHS