IntroductionObstructive sleep apnea (OSA) is a respiratory sleep disorder. Many of these patients also exhibit autonomic alterations which can be observed through heart rate variability (HRV). Currently, one of the treatments for apnea is continuous positive airway pressure (CPAP).ObjectiveTo observe OSA patients treated with CPAP exhibit HRV changes at medium and long treatment period.MethodsThis is an integrative literature review conducted in May of 2018. The databases used for this research were PubMed, Scopus, Scielo and Pedro, the keywords used were “heart rate variability”, “obstructive sleep apnea” and “CPAP”. In this review was included original, published, randomized and non-randomized articles, released in the English language, before and up to April 2018, which specified the effects of CPAP therapy in autonomic dysfunction through the analysis of the HRV of patients diagnosed with OSA after at least one month of therapy.ResultsThe research of the literature produced 113 articles. After excluding duplicates and applying the inclusion and exclusion criteria, 8 articles were selected for this review.ConclusionIt was concluded that CPAP therapy is related to change in heart rate variability in patients with obstructive sleep apnea.