Serum cystatin C level is associated with locomotive syndrome risk and can be an early predictor in community-living people: The Yakumo study

Objectives: The locomotive syndrome (LS) risk has been recently proposed as a criterion for evaluating physical ability. Serum cystatin C level is an early renal function marker and a cardiovascular disease predictor. This study aimed to evaluate the relationship between serum cystatin C level and LS risk. Methods: We enrolled 54 participants and conducted the two-step test, stand-up test, 25-question geriatric locomotive function scale, LS risk test, Timed Up and Go test, back muscle strength, grip strength, blood test and serum cystatin C level measurement. A comparative study was conducted in participants with and without LS risk and in subgroups aged <60 and ≥60 years. Results: No significant difference was found in the serum cystatin C level in subgroups aged <60 years and without LS risk. However, it was significantly higher in subjects with LS risk and aged ≥60 years. The area under the curve of the serum cystatin C level for LS risk was 0.824. Conclusion: The serum cystatin C level is significantly related to LS risk and can be an early predictor. In middle-aged and elderly people with high serum cystatin C levels, it is strongly recommended to enforce LS risk test and intervention.