Correlation between functional capacity and oxidative stress and inflammation in hemodialysis patients

Patients with chronic kidney disease (CKD) may present impaired functional capacity due to peripheral muscle involvement. Oxidative stress and inflammation are probably involved in this pathophysiology. This study aimed to evaluate the association between functional capacity and biomarkers of oxidative stress as well as biomarkers of inflammation in patients under chronic hemodialysis therapy.

Cross-sectional study including 41 patients from a single hemodialysis center. Functional capacity was assessed through the 6-min walk test (6MWT). The assessed blood biomarkers were: malondialdehyde (MDA) (oxidative stress, TBARS method) and angiopoietin-2 (Ang-2) (inflammation, ELISA). The influence of gender on impairment of functional capacity was further explored.

There was an inversely proportional correlation between the 6MWD and MDA (r = -,322 and p = 0.040) and Ang-2 (r = -, 376 and p = 0.016) values. 6MWD was 370.9 ± 101.2 m and 391.4 ± 108.2 m in women and men, respectively (p < 0.001), which means 29.3% and 34.3% reduction of the expected values for healthy individuals from the same age range.

Patients with CKD under hemodialysis, regardless of gender, presented impaired performance in 6MWT and this impairment was associated with oxidative stress and inflammation.