The relationship between inflammatory markers (neutrophil/lymphocyte ratio and platelet/lymphocyte ratio) and apnea-hypopnea index (AHİ) in patients with obstructive sleep apnea syndrome

Introduction: Obstructive Sleep Apnea Syndrome (OSAS) is a disorder characterized by recurrent episodes of complete (apnea) or partial (hypnea) upper airway obstruction during sleep and often a decrease in blood oxygen saturation. In some studies, a positive correlation was found between Neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) values and the severity of diseases. The aim of our study is to determine the relationship between the neutrophil lymphocyte ratio and platelet lymphocyte ratio obtained from a simple blood test such as complete blood count to predict the severity of the disease. Methods: The age, gender, smoking history, height, weight, neck circumference, complete blood count, thyroid function test, respiratory function test, cholesterol levels, posterior anterior lung films, Apnea-Hypopnea Indices, diagnosed comorbidities, and treatments received of 191 patients diagnosed with Obstructive Sleep Apnea at the Chest Diseases Sleep Laboratory of Çukurova University Medical Faculty Hospital between January 16, 2021, and December 31, 2021, were examined and recorded retrospectively from the hospital automation system and files. Results: The mean age of the patients was 50.1±11.5 years; 142 (74.3%) were male.Of the patients, 95 (49.7%) were smokers, with an average smoking duration of 20.4±10.5 pack-years. The rate of comorbidity was higher in female patients than in male patients (p=0.015). While there was a significant difference between the BMI values of the patients and the AHI groups (p=0.021), it was determined that this difference was due to the higher BMI values of the patients in the AHI group with the severe group compared to the patients with the medium group in the AHI group. It was observed that there was a negative correlation between the AHI value and the lymphocyte value of the patients, and a weak positive relationship between the TG values and AHI (r=0.248; r=0.153), respectively. In addition, a weak positive correlation was found between NLR and PLR values (r=0.162; r=0.175, respectively). In the study, according to the diagnostic test performances of NLR and Platelet/Lymphocyte values evaluated with AHI mild+moderate and severe groups; The sensitivity of the NLR value was 47.4%; The sensitivity of the PLR ratio was observed to be 62.26%; Platelet/Lymphocyte ratio was found to be the best diagnostic test performance. Discussion and Conclusion: Increased NLR in OSAS may be secondary to inflammation caused by apnea and hypopnea in these patients, due to comorbid diseases and due to neutrophil dominance in the upper airways. We think that NLR and PLR may be useful in predicting and showing the severity of the disease in OSAS patients with a cheap and practical approach that can be easily obtained by whole blood measurement, but more comprehensive and multicenter studies are still needed to better understand the relationship between AHI and NLR and PLR in OSAS. Keywords: Sleep apnea, neutrophil/lymphocyte ratio, platelet/lymphocyte ratio, AHI