Dialysis leads to impaired cardiovascular functional capacity in CKD patients: JAHA

USA: Dialysis initiation in patients with chronic kidney disease is associated with a significant decline in cardiovascular functional capacity and performance, which may predispose patients to functional dependence, reports a cross‐sectional study published in the Journal of the American Heart Association.

The initiation of dialysis is a life‐altering transition characterized by a heightened risk for cardiovascular disease and mortality in patients with end‐stage kidney disease (ESKD). In chronic kidney disease (CKD), the development of cardiovascular disease is attributed to both traditional and nontraditional risk factors and the transition to dialysis dependency introduces additional stressors.

The cardiovascular mortality rate in patients with ESKD is at its highest during the first year of dialysis, and ≈80% of cardiovascular deaths in patients on dialysis are secondary to primary arrhythmia or sudden cardiac death. However, clinical practice lacks uniformly accepted standardized diagnostic tools for screening and identifying patients with CKD who are at increased risk of cardiovascular events. Assessment of oxygen uptake at peak exercise (VO2Peak) is widely accepted as a robust measure of cardiovascular functional capacity. To date, the alterations in cardiovascular functional capacity during the first‐year incident dialysis are largely unknown.

Eliott Arroyo, Indiana University School of Medicine, IN, USA, and his research team conducted a study to assess ventilatory exercise response measures in patients within 1 year of initiating dialysis.

Researchers included 241 patients(age, 48.9 [15.0] years) with CKD stage 5 from the CAPER study and the intradialytic low‐frequency electrical muscle stimulation pilot randomized controlled trial cohorts for the present study. Of the total participants, 42 were predialytic (mean estimated glomerular filtration rate, 14 mL•min−1•1.73 m−2), 54 had a dialysis vintage ≤12 months, and 145 had a dialysis vintage >12 months. Patients underwent cardiopulmonary exercise testing and echocardiography.

Key findings of the study,

• Patients with dialysis vintage ≤12 months exhibited a significantly impaired cardiovascular functional capacity, as assessed by oxygen uptake at peak exercise compared to predialysis.

• Patients with dialysis vintage ≤12 months also exhibited reduced peak workload, impaired peak heart rate, reduced circulatory power, and increased left ventricular mass index compared with predialysis.

• After excluding those with a prior kidney transplant, dialysis vintage >12 months exhibited a lower oxygen uptake at peak exercise compared with dialysis vintage ≤12 months. 

Researchers conclude that cardiovascular functional capacity (as assessed by oxygen uptake at peak exercise) is severely impaired after initiation of dialysis in patients with advanced chronic kidney disease and this may predispose them to functional dependence. Thus, the patients in this transition are an exceptionally vulnerable population.

The present study provides a rationale for further prospective studies that would assess cardiovascular functional changes using cardiopulmonary exercise testing during the transition to the dialysis period.

Reference:

Arroyo E, Umukoro PE, Burney HN, Li Y, Li X, Lane KA, Sher SJ, Lu TS, Moe SM, Moorthi R, Coggan AR, McGregor G, Hiemstra TF, Zehnder D, Lim K. Initiation of Dialysis Is Associated With Impaired Cardiovascular Functional Capacity. J Am Heart Assoc. 2022 Jul 19;11(14):e025656. doi: 10.1161/JAHA.122.025656.