# Predictive factors for short-term and 3-month outcomes in patients with obstructive sleep apnea and anterior circulation stroke without large artery occlusion

## TL;DR

This study examines how obstructive sleep apnea and inflammation affect stroke outcomes, finding that a pre-stroke OSA history may be linked to better recovery.

## Contribution

The study identifies novel associations between OSA history and improved stroke outcomes in patients without large artery occlusion.

## Key findings

- A pre-stroke history of OSA was significantly associated with lower NIHSS and mRS scores at discharge and 3 months.
- Higher WBC counts were linked to worse outcomes, while lower PDW was associated with better short-term and 3-month outcomes.
- OSA was not associated with increased stroke severity or poorer prognosis in anterior circulation AIS without LAO.

## Abstract

Obstructive sleep apnea (OSA) has been recognized as a potential risk factor for stroke. Among the pathophysiological mechanisms involved in stroke, neuroinflammatory response has gained increasing attention. However, the influence of OSA and inflammation on stroke prognosis remains insufficiently clarified.

A retrospective analysis was conducted using clinical data from patients diagnosed with acute ischemic stroke (AIS) due to non-Large Artery Occlusion (LAO) in anterior circulation who were admitted between May 2018 and October 2021. Patients were stratified based on documented pre-stroke history of OSA. Multiple linear regression was employed to examine associations among hematological parameters, vascular risk factors, and clinical outcomes of AIS.

No statistically significant differences were observed between the OSA and non-OSA groups in terms of National Institutes of Health Stroke Scale (NIHSS) scores at admission, modified Rankin Scale (mRS) scores at discharge, or mRS scores at the 3-month follow-up (all p > 0.05). However, the multiple linear regression analysis revealed that a pre-stroke history of OSA was significantly associated with lower discharge NIHSS scores (p = 0.005), lower discharge mRS scores (p = 0.001), and lower 3-month mRS scores (p = 0.004). Platelet distribution width (PDW) was positively associated with higher discharge mRS scores (p = 0.018) and 3-month mRS scores (p = 0.006). Elevated white blood cell (WBC) counts were positively associated with discharge NIHSS (p = 0.001), discharge mRS (p < 0.001), and 3-month mRS (p = 0.001).

Lower WBC count and the presence of a pre-stroke OSA history may be associated with less severe stroke presentation and more favorable functional outcomes both at discharge and at 3 months post-stroke. Additionally, a lower PDW might associated with better short-term and 3-month outcomes. In cases of anterior circulation AIS without LAO, our findings did not reveal an association between pre-stroke history of OSA with increased stroke severity or poorer prognosis.