Association of estimated glomerular filtration rate with the incidence of sleep apnea syndrome

Study Objectives. Sleep apnea syndrome (SAS) is potentially linked to life-threatening conditions. The decline in kidney function is involved in the development of various diseases; however, it remains unclear whether it is implicated in the onset of SAS. Therefore, this study aimed to investigate the relationship between kidney function and the incidence of SAS. Methods. The association of estimated glomerular filtration rate (eGFR) with the incidence of SAS was assessed retrospectively using real-world administrative claims and health checkup data collected between April 2014 and November 2022. To strengthen robustness, three stratified analyses and four sensitivity analyses were conducted. Results. We assessed 1 589 259 individuals for the analysis. During a median (interquartile range) follow-up of 1167 (652–1699) days, 11 054 cases of SAS events were documented. Multivariable Cox regression analyses after adjusting for potential confounders, including age, sex, body mass index, hypertension, diabetes, dyslipidemia, cigarette smoking, alcohol drinking, and physical inactivity, demonstrated that the decrease in eGFR (eGFR ≥ 90, 60–89, 45–59, 30–44, and <30 mL/min/1.73 m²) was associated with a higher risk of SAS (hazard ratio [95% confidence intervals]; 1 [reference value], 1.13 [1.06–1.20], 1.22 [1.13–1.32], 1.34 [1.17–1.52], 1.82 [1.43–2.33]). In the restricted cubic spline regression model, the risk of developing SAS increased with the reduction in eGFR. The results of the sensitivity analyses were consistent with the primary findings. Conclusion. Our analysis utilizing a large-scale population-based cohort concluded that reduced eGFR is associated with the risk of developing SAS in a dose-dependent manner.