Obstructive sleep apnea is associated with postoperative dialysis in patients who underwent coronary artery bypass grafting.

Background: The incidence of obstructive sleep apnea (OSA) is significantly higher in patients who undergo coronary artery bypass grafting (CABG). OSA is correlated with a higher incidence of postoperative complications in patients undergoing CABG. However, whether OSA is associated with a decrease in renal function and a higher incidence of dialysis after CABG remains unclear.

Methods: Data from 178 consecutive patients who underwent isolated CABG at Anzhen Hospital between June 2019 and June 2020 were analyzed. Polysomnography was performed in all the patients.

Results: A total of 142 (79.8%) patients were diagnosed with OSA, 78 with mild OSA, and 64 with moderate-to-severe OSA. Compared to patients without OSA, the level of creatinine was significantly increased, and the level of estimated glomerular filtration rate (eGFR) was decreased in patients with OSA. In addition, the percentage of patients undergoing dialysis during the perioperative period increased with the severity of OSA (0.0% vs. 2.6% vs. 18.8%, P=0.02). Multiple linear regression analysis showed that age (β=-0.29, P<0.001), male sex (β=-0.17, P=0.02), apnea-hypopnea index (AHI) (β=-0.35, P<0.001), and creatinine (β=-0.78, P<0.001) were independently associated with a decrease in eGFR (adjusted R2=0.376, P<0.001). However, in the multivariate logistic regression model, we found that the level of eGFR (OR =0.94, 95% CI: 0.89-0.99, P=0.02) and AHI (OR =1.07, 95% CI: 1.01-1.13, P=0.02) were independently associated with dialysis after CABG.

Conclusions: OSA is associated with a decrease in renal function and is an independent risk factor for postoperative dialysis in patients who undergo CABG.