# Usefulness of Blood Biomarkers in Screening Patients with Obstructive Sleep Apnea: Could Albumin Indices and Uric Acid-to-HDL Ratio Be New OSAS Severity Indices?

## TL;DR

This study suggests that blood biomarkers like albumin indices and uric acid-to-HDL ratio could help identify and assess the severity of obstructive sleep apnea syndrome (OSAS) in patients.

## Contribution

The study identifies BAR, RAR, and UHR as novel hematological indices for predicting and assessing OSAS severity.

## Key findings

- BAR, RAR, and UHR showed significant associations with the presence and severity of OSAS.
- These indices could serve as low-cost biomarkers for early prediction of OSAS in clinical settings.
- UHR was found to be the strongest predictor of severe OSAS.

## Abstract

What are the main findings?
Hematological parameters showed significant differences in the presence and severity of OSAS.BAR, RAR, and UHR emerged as important hematological indices associated with OSAS.

Hematological parameters showed significant differences in the presence and severity of OSAS.

BAR, RAR, and UHR emerged as important hematological indices associated with OSAS.

What is the implication of the main finding?
Hematological parameters can be used as simple and low-cost biomarkers for the early prediction of OSAS.In clinical settings with limited access to PSG, hematological indices can guide the prioritization and decision-making process for patients who require referral for PSG.

Hematological parameters can be used as simple and low-cost biomarkers for the early prediction of OSAS.

In clinical settings with limited access to PSG, hematological indices can guide the prioritization and decision-making process for patients who require referral for PSG.

Background and Objectives: Hematological parameters are increasingly being investigated as readily accessible biomarkers for the diagnosis of obstructive sleep apnea syndrome (OSAS). In our study, we aimed to investigate the relationship between OSAS and albumin indices and the uric acid-to-HDL ratio (UHR). Methods: The demographic and laboratory data and AHI (apnea–hypopnea index) values of 613 patients who underwent polysomnography were obtained retrospectively from their files. Blood parameters such as white blood cells (WBCs), red blood cell distribution width (RDW), red blood cells (RBCs), hemoglobin (Hb), hematocrit (Hct), platelets (PLTs), C-reactive protein (CRP), albumin, blood urea nitrogen (BUN), and high-density lipoproteins (HDLs) were obtained from the files. Laboratory indices such as the BUN-to-albumin ratio (BAR), neutrophil-to-albumin ratio (NAR), RDW-to-albumin ratio (RAR), CRP-to-albumin ratio (CAR), and UHR were calculated. OSAS was categorized as simple snoring (SS) (control) (AHI < 5), mild (5 ≤ AHI < 15), moderate (15 ≤ AHI < 30), and severe (AHI ≥ 30). The patients were also grouped as severe (AHI ≥ 30) and non-severe (5 > AHI < 30) OSAS and compared in terms of laboratory parameters and indices. Results: Of the 613 participants, 366 (59.7%) were men, and the average age of participants was 55.22 ± 11.13 years. The biomarkers such as RBCs, Hb, Htc, CRP, BUN, creatinine, uric acid, HDLs, CAR, RAR, BAR, and UHR showed significant differences between OSAS patients and controls. WBCs, basophils, RBCs, RDW, Htc, PLTs, HDLs, uric acid, RAR, NAR, and UHR indices were significantly different between the severe OSAS and non-severe OSAS groups (p < 0.05). BAR (OR = 1.151; CI = 1.056 − 1.256; p = 0.001) and UHR (OR = 2.257; 95% CI = 1.507 − 3.382; p < 0.001) were the most important indices predicting OSAS, while RAR (OR = 1.844; CI = 1.224 − 2.778; p = 0.003) and UHR (OR = 2.203; 95% CI = 1.496 − 3.243; p < 0.001) were the strongest indices associated with severe OSAS. Conclusion: In our study, RAR, BAR, and UHR indices were closely associated with the presence and severity of OSAS. These indices can be considered low-cost, readily available methods for predicting OSAS patients.