Negative effects of chronic kidney failure on lung function and functional capacity.

Objective: To evaluate lung function and functional capacity in patients with chronic kidney failure (CKF) undergoing dialysis and in patients after kidney transplant.

Methods: Seventy-two participants were evaluated: 32 patients with CKF on dialysis (DG) for at least six months, ten patients who had kidney transplants (TG) at least six months earlier, and 30 healthy subjects as a control group (CG). All groups were evaluated using spirometry, with maximum inspiratory pressure (MIP) and maximum expiratory pressure (MEP), and using the six-minute walking test (6MWT). The SPSS 12.0 software was used for statistical analysis, with a minimum significance level of alpha<0.05.

Results: There was a decreased lung function in the DG for FVC, FEV1, MVV, VC, MIP and MEP, and decreased FEV1 and MVV in the TG compared to the CG (one-way ANOVA/Fisher's post-hoc; p<0.01). There was also an association (chi-square) between decreased MIP and belonging to the DG (alpha=0.5, p<0.001), between lower performance in the 6MWT for the DG and TG (p<0.01) compared to the CG (one-way ANOVA/Fisher's post-hoc), and between MIP and MEP (Pearson's coefficient; r=0.752; p<0.01).

Conclusions: Patients with CKF undergoing dialysis showed impaired functional capacity and lung function that were not completely reverted in the kidney transplant patients.