The lower the renal function in patients with chronic renal disease, the greater the improvement in the renal function cardiac rehabilitation provides

Abstract

Abstract Background Our previous study suggested that cardiac rehabilitation (CR) resulted in a significant improvement in the renal function in cardiac vascular disease (CVD) patients with chronic renal disease (CKD), using cystatin C. However, whether the difference in the severity of the renal impairment at the beginning of the CR affects the degree of the improvement in the renal function after CR is unknown. Methods We studied 203 CVD patients (155 males; 73 y/o) with CKD (15≤estimated glomerular filtration rate based on the serum cystatin C concentration [eGFRcys]<60 ml/min/1.73m2) who participated in our 3-month CR program. The eGFRcys was examined at the beginning and end of the CR. In addition, the patients were divided into 3 groups according to the severity of the renal impairment at the beginning of the CR: CKD G3a group (45≤eGFRcys<60 ml/min/1.73m2, n=122), CKD G3b group (30≤eGFRcys<45 ml/min/1.73m2, n=60), and CKD G4 group (15≤eGFRcys<30 ml/min/1.73m2, n=21). We compared the renal function at the beginning and end of the CR in each of the 3 groups. Moreover, we evaluated the correlation between the eGFRcys at the beginning of the CR and the change in the eGFRcys (%ΔeGFRcys). Results In all the study patients, the eGFRcys improved after the CR (45.5 to 47.7 ml/min/1.73m2, p<0.001). In the CKD G3b and G4 groups, the eGFRcys also improved (38.4 to 41.5 ml/min/1.73m2, p=0.001; 23.2 to 28.0 ml/min/1.73m2, p=0.016). However, in the CKD G3a group, the eGFRcys did not improve after the CR (52.9 to 54.2 ml/min/1.73m2, p=0.074) (Figure 1). The univariate analysis results showed that the %ΔeGFRcys was significantly negatively correlated with the eGFRcys at the beginning of the CR (p=0.016, r=−0.26, Figure 2). Conclusion The greater the renal dysfunction in the CVD patients with CKD was, the greater the improvement in the renal function after participating in the CR program. Funding Acknowledgement Type of funding source: None