Assessment of the Prevalence of Sleep Apnea in Patients with Chronic Kidney Disease

Sleep apnea is a common but underdiagnosed comorbidity in patients with chronic kidney disease (CKD), and its severity with declining renal function. To determine the prevalence of sleep apnea in patients with CKD using the Apnea-Hypopnea Index (AHI) on polysomnography, and to examine its association with CKD stage and estimated glomerular filtration rate (eGFR). An observational, cross-sectional study was conducted over six months in the renal department of a tertiary care hospital and enrolled 100 patients with CKD (stages 1–5, age ≥18 years, both sexes). Sleep apnea risk was screened using the stop-bang questionnaire; patients classified as moderate or high risk underwent polysomnography for AHI-based diagnosis and severity grading. Associations between CKD stage and AHI were analysed with one-way ANOVA, and the eGFR–AHI relationship was assessed using Pearson correlation. Of 100 patients, STOP-BANG classified 60% as high risk and 11% as moderate risk. Among the 71 patients who underwent polysomnography, AHI-confirmed sleep apnea was severe in 42%, moderate in 19%, and mild in 10%. Mean AHI rose progressively with CKD stage, from 20.67 in stage 2 to 48.90 in stage 5 (one-way ANOVA, p < 0.0000). eGFR correlated strongly and negatively with AHI (r = −0.7891, p < 0.001). Only male gender was significantly associated with sleep apnea among candidate risk factors (p = 0.026). Sleep apnea is highly prevalent among patients with CKD and becomes progressively more severe as renal function declines. STOP-BANG-based screening followed by confirmatory polysomnography identifies a substantial burden of unrecognised sleep apnea and supports routine screening, particularly in advanced CKD.