The Outcome of Chronic Kidney Disease Patients With Obstructive Sleep Apnea Syndrome

Inclusion Criteria: * Voluntarily sign the informed consent form; * Aged ≥ 18 years and \< 75 years; * Patients with CKD stages 3-4, with an eGFR of 15-60 ml/min/1.73m² calculated using the CKD-EPI formula for at least 3 months. Exclusion Criteria: * Patients receiving oxygen therapy or continuous positive airway pressure (CPAP) treatment; * Patients with other sleep disorders, including restless legs syndrome, periodic limb movement disorder, etc.; * Patients with other severe comorbidities: Severe heart failure (NYHA class III or IV); Myocardial infarction, unstable angina, or stroke within the past 3 months; Severe arrhythmias requiring medication or device therapy; Respiratory diseases, including COPD, asthma, thoracic deformities, etc.; Neurological disorders, including myasthenia gravis, Parkinson's disease, Alzheimer's disease, etc.; Active liver disease or severe hepatic insufficiency; Psychiatric conditions, including depression, anxiety disorders, etc.; History of malignancy within the past 5 years (except cured basal cell carcinoma); Uncontrolled hyperthyroidism; * Patients who underwent surgery or had acute infections within the past 3 months; * Current heavy alcohol consumption:Females: \>3 drinks/day or \>7 drinks/week; Males: \>4 drinks/day or \>14 drinks/week (1 standard drink = 14g of alcohol) * Current use of medications that may severely interfere with sleep, such as antipsychotics, antiepileptics, antiparkinsonian drugs, antidepressants, opioids, etc.; * Females who are pregnant or lactating at screening or baseline; * Inability to comply with the study due to: Low education level, language barriers, inability to tolerate or complete sleep monitoring, or other reasons preventing completion of study procedures (e.g., follow-up); * Deemed unsuitable for participation by the investigator's judgment.