Preliminary study on the relationship between OSA and renal function

Abstract

Objective:To explore the relationship between obstructive sleep apnea(OSA) and renal function. Method:We collected the clinical data of 487 patients who underwent sleep monitoring in our hospital from January 2013 to December 2017 and excluded history of chronic heart disease, acute and chronic glomerulonephritis, and pyelonephritis. Among the 487 patients, 54 were in nonOSA control group and 433 were in OSA group, including 64 patients with mild OSA, 77 patients with moderate OSA, 108 patients with severe OSA, and 188 patients with extremly severe OSA. The eGFR was calculated using an equation combined serum creatinine and cystatin C. Then propensity score matching(PSM) was used to reduce differences in confounders among groups. The differences of creatinine, cystatin and eGFR between the control group and different degrees of OSA were compared, and the relationship between OSA severity and renal dysfunction was analyzed.Result:There was no statistically significant difference in creatinine between the OSA group and the control group. Serum cystatin C levels in the moderate OSA group and the extremly severe OSA group were higher compared with the control group(0.90±0.18)mg/L, (0.82±0.21) mg/L,P=0.026;(0.92±0.22) mg/L,(0.82±0.21) mg/L,P=0.006,there was no statistically significant difference in cystatin C level of mild OSA group or severe OSA group compared with the control group.The eGFR levels in the moderate OSA group and extremly severe OSA group were lower than that in the control group, 100.64±16.09, 108.57±19.31,P=0.012; 102.03±18.39, 108.57±19.31, P=0.024.After matching with the PSM, the serum cystatin C levels in the moderate OSA group and in the extremely severe OSA group were higher compared with the control group, (0.91±0.19) mg/L,P=0.028;(0.91±0.23) mg/L,P=0.031;(0.82±0.21) mg/L, but only in moderate OSA group, eGFR was lower than the control group,100.86±17.31,108.57±19.31,P<0.05. Conclusion: The renal function of OSA patients has different degrees of impairment. Renal function impairment and the severity of OSA do not show a single linear relationship.