Alterations in platelets according to the severity of obstructive syndrome of apnoea-hypopnea

Introduction: There are important cardiovascular complications associated to Obstructive Syndrome of Apnoea-Hypopnea (OSA). Platelets play a fundamental role in the development of atherothrombosis. Several studies show a relationship between the activation of platelets in OSA and an increase of its aggregation. Objective: Evaluate the behavior of platelets parameters in the hemogram of patients with OSA. Methods: Retrospective study of patients referred to the Respiratory Sleep Pathology Appointment. Patients with diseases associated with OSA, active hematological and neoplastic diseases were excluded. Hemogram was requested to every patient. The study sample was divided into four groups according to the Apnea-Hypopnea Index (AHI); Group 1:control (AHI <5), Group 2:mild OSA, Group 3:moderate OSA, Group 4:severe OSA. The platelets parameters were compared (platelets number, mean platelet volume (MPV), platelet distribution width (PDW) and plateletcrit (PTC) between the different groups. Results: The final sample had 563 individuals. In the patients with OSA MPV was higher and the number of platelets was lower. In the patients with OSA, MPV was higher and inversily, the number of platelets was lower. There were no differences between patients with OSA comparing to Group 1, regarding PTC or PDW. It was found a significant correlation between AHI and MPV and between Dessaturation Index (DI) and MPV. Conclusions: In the platelets of patients with OSA there were significant quantitative and morphological alterations comparing to control patients. The alterations were progressive according to the OSA severity. There was a significant correlation, although not strong, between MPV/AIH and MPV/DI.