Chronic Kidney Disease and Concomitant Sleep Apnea Are Associated with Increased Overall Mortality: a Meta-analysis

Purpose: Sleep apnea (SA) is common in advanced chronic kidney disease (CKD) patients. However, the association between CKD with concomitant SA and overall mortality remains inconclusive.

Methods: Ovid MEDLINE, EMBASE, and the Cochrane Library were searched for eligible publications, including non-transplant CKD patients aged > 18 years with co-existing SA. CKD is defined by estimated glomerular filtration rate of < 60 mL/min/1.73 m.

Results: Seven observational studies (n = 186,686) were included in the meta-analyses. 94.2% had end-stage kidney disease (ESKD) requiring hemodialysis (HD), 5.0% had ESKD requiring peritoneal dialysis (PD), and 0.8% had non-dialysis CKD. The mean age was 76.8 ± 2.2 years. Most patients were male (53.4%) and white (76.8%). Up to 39.3% had diabetes. The mean body mass index was 26.0 ± 0.6 kg/m. Among patients with advanced CKD and SA, the pooled estimated odds ratios (OR) for overall mortality and cardiovascular events were 2.092 (95% CI, 1.594-2.744) and 1.020 (95% CI, 0.929-1.119), respectively, compared to patients with CKD alone. The OR was 2.145 (95% CI, 1.563-2.944) when studies with polysomnography-diagnosed SA were examined independently. No potential publication bias was detected. There were no significant differences in odds ratios for overall mortality, based on subgroup analyses.

Conclusion: Co-existence between advanced CKD and SA is associated with increased overall mortality, but not cardiovascular (CV) events when compared with CKD alone. The analysis of CV events requires additional studies to confirm our findings. Moreover, clinical interventions aiming to prevent the progression of SA and CKD are encouraged.