Aerobic exercise capacity is maintained over a 5-year period in mild-to-moderate chronic kidney disease: A longitudinal study

Abstract Background: Aerobic exercise capacity is reduced in non-dialysis chronic kidney disease (CKD), but little is known about the magnitude of changes in exercise capacity over time. In a 5-year-prospective study, we evaluated exercise capacity and known determinants of exercise capacity in patients with mild-to-moderate CKD attending a specialist nephrology clinic. Methods: We included 52 individuals with CKD stage 2–3 and 54 age- and sex-matched healthy controls. Peak workload was assessed through a maximal cycle exercise test. Muscle strength and lean body mass, cardiac function, vascular stiffness, renal function and haemoglobin level were evaluated. Tests were repeated after 5 years. Statistical analysis of longitudinal data was performed using linear mixed models. Results: Exercise capacity did not change significantly over time in either CKD individuals or controls, although the absolute workload levels were significantly lower in CKD individuals. Renal function decreased in both groups, with a faster decline in CKD (p = 0.05 between groups). Peak heart rate, haemoglobin level, handgrip strength, lean body mass and cardiovascular function did not decrease significantly over time in CKD individuals. Physical activity level increased over 5 years only in the CKD group. Conclusions: Aerobic exercise capacity and peak heart rate are maintained over 5 years in a group of patients with well-controlled CKD grade 2–3, despite a slight reduction in glomerular filtration rate, mirroring the lack of progression of cardiovascular and muscular dysfunction in this group.