The role of obstructive sleep apnea, neurofilaments and early CPAP intervention in post-stroke cognitive recovery

Stroke is a leading cause of disability worldwide, with cognitive impairment following stroke influenced by a complex interplay of modifiable and non-modifiable risk factors. This study investigated the impact of obstructive sleep apnea (OSA) on cognitive outcomes after ischemic stroke (IS) and the predictive value of plasma neurofilament light chain (pNFL) levels. Seventy-three acute IS patients were analyzed, with 59 completing a three-month follow-up. Cognitive function (Montreal Cognitive Assessment, MoCA) was assessed. Patients underwent polygraphic screening for OSA in the acute phase, with treatment recommended when indicated, and pNFL levels measured at baseline and follow-up. Results showed that 93.2 % of IS patients had OSA. Forty (72.7 %) of OSA patients (moderate, severe OSA) were recommended continuous positive airway pressure (CPAP). CPAP-treated patients in the acute phase demonstrated cognitive improvement at three-month follow-up (CPAP-treated: MoCA 23 vs 25 points, CPAP indicated untreated, MoCA 22 vs 22 points, p = 0.05). However, long-term adherence to CPAP was poor - only 25 % remained on therapy at three months. While pNFL levels correlated with infarct volume and significantly decreased over time, no correlation was found between OSA severity and CPAP treatment. Regression analysis identified age, prior stroke history, and anxiety as key predictors of cognitive and functional post-stroke outcome. Early CPAP therapy could contribute to improved post-stroke cognitive performance. Decline in pNFL levels shows ongoing neuronal recovery; a direct relationship with OSA is inconclusive. Furthermore, advanced age, history of prior stroke, and anxiety symptoms emerged as significant contributors to poorer cognitive outcomes.