Changes in spirometry over time in uremic patients receiving long-term hemodialysis therapy

Complications of respiratory system in patients suffering from chronic renal failure who are treated with regular haemodialysis are well known. However, the influence of the duration of haemodialysis on pulmonary function is less understood. The aim of this study was to determine spirometry changes in patients on chronic haemodialysis over a five-year period. We tested 21 patients, out of which 11 female and 10 male, mean age of 50 (+/- 11) years. The mean duration of haemodialysis was 52.2 (+/- 44.7) months at the time of the inclusion. We performed spirometry testings in all patients, one hour before start and one hour after completion of haemodialysis. All parameters of spirometry recorded one hour after completion of haemodialysis (FVC, FEV1, FEF75, 50, 25, % of predicted), improved significantly (p < 0.01). After five years, only FVC demonstrated significant decline and none of the recorded spirometry parameters improved significantly one hour post haemodialysis compared to pre-haemodialysis period. Analysis of post-dialysis parameters of spirometry at the study onset and following five years of haemodialysis showed that all parameters, except FEF50 (p > 0.05), significantly deteriorated (p < 0.01). Patients who are on long-term haemodialysis show a significant decline in FVC following five years of treatment. Although the spirometry changes in observed population treated with chronic haemodialysis have reversible character during the first years of renal replacement therapy, five years after these changes become irreversible.