#2694 URAEMIC CARDIOMYOPATHY AS PREMATURE PRESBYCARDIA

Abstract Background and Aims Presbycardia, the age-related decline in cardiac function, has been shown in the general population by demonstrating gradual decline in peak cardiac performance with advancing age [1]. Chronic kidney disease (CKD) has shown phenotypic similarities with premature aging. Studies have shown accelerated vascular aging and skeletal muscle wasting in CKD. However, it is not known whether CKD patients show age related decline in cardiac function and whether the impairment is more pronounced for the given age (premature presbycardia). In the present study, we set out to test the hypothesis that CKD patients have premature presbycardia by measuring peak cardiac power (CPOpeak) non-invasively across different age groups. Method A cross sectional study (n = 170) of healthy male volunteers (n = 100) and male CKD patients (n = 70) spanning ages 19 to 75 years. CKD patients were grouped into early (CKD 2–3, n = 29) and late CKD (CKD 4–5, n = 41). Patients with diabetes or any known cardiovascular diseases were excluded. CPOpeak was measured using a specialised cardiopulmonary exercise test (CPX) using CO2 rebreathing method [2]. The association between age and CPOpeak was evaluated. The regression lines of CKD patients and healthy volunteers were compared using ANCOVA. P<0.05 is considered significant. Results The mean eGFR of early CKD and late CKD were 57.8±17.2 ml/min and 16.8±5.8 ml/min respectively. The mean CPOpeak of the study groups were 5.35±0.94 W (Control), 4.93±0.71 W (early CKD) and 4.26±0.69 W (late CKD). Fig. 1 shows the association between CPOpeak and age along with the regression equations for the individual study groups. Comparison of the regression lines using ANCOVA did not show any difference in slopes between the groups (P = NS). There was a diminution in CPOpeak of 0.2W per 10 years of advancing age. However, for any given age, the CPOpeak was diminished by 0.38 W in early CKD (P = 0.023) and 0.93 W in late CKD (P<10−3) compared to control. In other words, the cardiac age was older by 19 years in early CKD and by 46.5 years in late CKD compared to healthy volunteers. Conclusion The results demonstrate that CKD is associated with premature presbycardia. This phenomenon may offer explanation for the high prevalence of heart failure in advanced CKD. Further studies exploring the underlying mechanisms of premature aging in CKD may be worthwhile in the future.