Impact of cardiac rehabilitation on renal function in patients with and without chronic kidney disease after acute myocardial infarction

Background: Although there is a general fear that exercise training might deteriorate renal function in chronic kidney disease (CKD) patients, the effect of cardiac rehabilitation (CR) on renal function in acute myocardial infarction (AMI) patients with CKD remains unknown. We sought to determine whether CR is associated with amelioration or deterioration of renal function in such patients. Methods and Results: We enrolled 528 AMI patients who participated in a 3-month CR program. Clinical data before and after CR were compared according to participation in CR and comorbidities. In patients without CKD (estimated glomerular filtration rate [eGFR] ≥60ml•min^-1•1.73m^-2, n=348), peak oxygen uptake (VO₂) and B-type natriuretic peptide (BNP) improved without a change in eGFR. In contrast, in patients with CKD (eGFR <60ml•min^-1•1.73m^-2, n=180), eGFR improved (48±12 to 53±15ml•min^-1•1.73m^-2, P<0.001), together with improvements in peak VO₂ and BNP. When patients with CKD were divided into non-active (≤1time/week, n=70) and active participants (≥1.1time/week, n=110) according to attendance in CR, active participants showed an improvement in eGFR (50±10 to 53±13ml•min^-1•1.73m^-2, P<0.001), whereas eGFR did not change in non-active participants. Similar results were obtained in each subgroup of patients with hypertension, dyslipidemia, or diabetes mellitus. Conclusions: In AMI patients with CKD, active participation in CR was associated with improved peak VO₂, BNP, and eGFR.