Patients undergoing dialysis experience decreases in physical function; however, few data exist on physical function in pre-dialysis patients with chronic kidney disease (CKD). The primary objective of this study was to clarify physical function in pre-dialysis patients according to CKD stage.

This was a cross-sectional study of 120 ambulant pre-dialysis CKD stage 2 or higher patients (85 male, 35 female; mean age 66.5 years) who visited St. Marianna University School of Medicine Hospital. Participants were grouped according to CKD stage as follows: stage 2 (n = 17), stage 3 (n = 55), stage 4 (n = 25), and stage 5 (n = 23). Handgrip strength, knee extensor muscle strength, single-leg stance time, and maximum gait speed were used to assess physical function. Clinical laboratory tests were also examined at the same time as physical function measurements.

All indices of physical function decreased according to the progression of CKD. Each physical function index was significantly lower in CKD stage 4 or 5 patients than CKD stage 2 or 3 patients. All physical function indices showed a positive correlation with estimated glomerular filtration rate (eGFR), blood hemoglobin level, and serum albumin level, and a negative correlation with urinary protein levels. In multiple regression analysis, age, female sex, body mass index, eGFR and urinary protein were significantly correlated with indices of physical function.

Physical function in pre-dialysis CKD patients decreased as the disease progressed according to stage. Early intervention in CKD patients might delay the loss of physical function.