The association of complete blood count parameters and obstructive sleep apnea in the Cypriot population

The hemocyte profile is a frequently requested clinical laboratory test. However, the analysis of blood cell indexes of obstructive sleep apnea (OSA) patients in previous studies was not decisive. This study aimed to fully analyze the blood count patterns in OSA patients.

We retrospectively studied 114 patients, referred to the sleep center of Nicosia General Hospital in Cyprus and had sleep studies performed from July 2022 until October 2024. Based on apnea hypopnea index (AHI), patients were divided into four groups: control (AHI < 5, n = 12), mild OSA (5 ≦ AHI < 15, n = 35), moderate OSA (15 ≦ AHI < 30, n = 28), and severe OSA (AHI ≧ 30, n = 39). We evaluated sleep parameters by type III with Nox T3s home sleep testing device. Patients with central sleep apnea syndrome, chronic respiratory failure and known haematological diseases were excluded.

Significant positive linear correlations of hematocrit, hemoglobin and red blood cells (RBC) with oxygen desaturation index (ODI) were observed, and inverse linear correlations with minimum SpO2. There was a significant positive linear correlation between hematocrit and duration SpO2 < 90%, but not with average SpO2. The values of mean platelet volume (MPV) had statistically significant positive linear correlations with ODI and minimum SpO2.

Our results indicate that subjects with severe OSA had higher hematocrit levels than subjects with no OSA or mild to moderate OSA. Even though MPV is associated with a higher degree of nocturnal hypoxemia, among the laboratory parameters that were investigated, only hematocrit can be used as an inexpensive tool for triaging OSA patients for evaluation in sleep laboratories.