Higher Serum-Soluble α-Klotho Level Does Not Predict Longer Survival after Stroke

Aims and Scope. Ischemic stroke (IS) is one of the main causes of death and disability worldwide. It has been suggested that the Klotho protein, playing a preventive role in the development of atherosclerosis, may be associated with a better recovery after IS. Therefore, the aim of this study was to analyze whether Klotho serum levels indeed correlate with long-term IS outcomes, such as overall survival (OS) and stroke-free survival (SFS). Material and Methods. The study group consisted of 217 patients with onset of IS symptoms within 24 hours before admission to the hospital. IS was diagnosed using the WHO criteria and radiology imaging. ELISA kits were used to assess soluble α-Klotho and fibroblast growth factor 23 serum levels. Results. There were 5 recurrent strokes and 89 deaths during the 36-month follow-up. Even though no significant differences in OS and SFS between soluble α-Klotho level tertile groups were recorded, unexpectedly, OS and SFS were highest in patients with the lowest soluble α-Klotho concentrations. Moreover, the Cox proportional models adjusted for established risk factors, kidney function, and the severity of stroke revealed that each 100 pg/mL increase in soluble α-Klotho levels was associated with decreased OS ( (0.908–0.995), ) and SFS ( (0.908–0.993), ). In addition, the α-Klotho to iFGF23 index was predicting neither OS nor SFS. Conclusion. Soluble α-Klotho levels in serum were not related to the severity of neurological deficits and long-term outcomes in patients with IS. No neuroprotective effect of soluble α-Klotho levels in patients with IS was demonstrated.