Physical performance, plasma S-klotho, and all-cause mortality in elderly dialysis patients: A prospective cohort study

Exp Gerontol. 2019 Jul 15:122:123-128. doi: 10.1016/j.exger.2019.05.003. Epub 2019 May 8.


The secreted protein form of the α-klotho gene, S-klotho, is gaining popularity as a predictor of overall morbimortality, and its role in dialysis patients has been recently highlighted. However, physical performance -which can be assessed through practical field-tests- might be a more practical prognostic marker. The present study aimed to analyze the relationship between physical performance, plasma S-klotho and all-cause mortality in this population. 30 male hemodialysis patients (71 ± 9 years) participated in this prospective, cohort study. Their plasma S-klotho levels and physical performance (assessed by means of the 6-minute walk test [6MWT], handgrip strength, and the sit-to-stand test [STS]) were determined at baseline, and the incidence of mortality was assessed 18-month later. Lower S-klotho levels were associated with a worse performance in all physical tests (all p < 0.05). 12 participants died during the 18 months following baseline measurements. An increased mortality risk was observed in those patients with a worse performance in the STS (RR: 3.0 [95%CI: 1.01-8.95], p < 0.05), the handgrip test (RR: 3.0 [95%CI: 1.01-8.95], p < 0.05) and the 6MWT (RR: 5.0 [95%CI: 1.31-19.07], p < 0.01), being the latter the best predictor of mortality. By contrast, this relationship was not found for plasma S-klotho (RR: 1.6 [95%CI: 0.65-1.35], p > 0.05). In summary, low plasma S-klotho levels are related to impaired physical performance in male dialysis patients. However, physical performance appears as a better and more practical predictor of mortality in this patient population.

Keywords: Biomarker; Physical performance; Physical tests; Predictors; Sarcopenia.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Biomarkers / blood
  • Female
  • Glucuronidase / blood*
  • Hand Strength*
  • Humans
  • Klotho Proteins
  • Logistic Models
  • Male
  • Middle Aged
  • Mortality*
  • Multivariate Analysis
  • Physical Functional Performance*
  • Predictive Value of Tests
  • Prospective Studies
  • Renal Dialysis / mortality*
  • Walk Test


  • Biomarkers
  • Glucuronidase
  • Klotho Proteins