On the other hand, OSA acts as an aggravating factor for CKD by promoting sustained or resistant hypertension, intermittent nocturnal hypoxia, activation of the renin-angiotensin-aldosterone system (RAAS), and persistent oxidative stress, all of which are believed to culminate in endothelial injury, tubulointerstitial fibrosis, and progressive decline in glomerular filtration rate26,28,32. Here, REN is linked to chronic kidney disease.