Abstract:

Objective To establish the reference range of serum cystatin C（Cys C） in elders in Shanghai. Methods A total of 7 277 individuals aged 60 to 89 years who underwent physical examination at Huadong Hospital Affiliated to Fudan University from January 2023 to August 2024 were enrolled. Totally，6 934 individuals aged <50 years who underwent physical examination at Huadong Hospital Affiliated to Fudan University from January to December 2024 were enrolled. Another 741 aged 20 to 89 years individuals who underwent physical examination at Huadong Hospital Affiliated to Fudan University from January to June 2025 were enrolled as the validation set. Serum Cys C levels were compared by gender and age groups. Spearman correlation analysis was used to evaluate the correlation between Cys C levels and age and gender. The 95% reference range of Cys C in elders was established according to the method in the Chinese health industry standard WS/T402—2024. Results There was statistical significance in serum Cys C levels between men and women and among different age groups in both ≥60-year-old and <50-year-old populations（P<0.001）. Cys C levels were positively correlated with age（r=0.206，P<0.001） and negatively correlated with gender（r=-0.322，P<0.001）. The reference range of serum Cys C in healthy elders in Shanghai was as follows：for men aged 60-69 years，0.66-1.16 mg·L^-1；for women aged 60-69 years，0.60-1.03 mg·L^-1；for men aged 70-79 years，0.70-1.23 mg·L^-1；for women aged 70-79 years，0.66-1.15 mg·L^-1；for men aged 80-99 years，0.73-1.30 mg·L^-1；and for women aged 80-99 years，0.64-1.22 mg·L^-1. The percentage of individuals in the validation set below the lower limit or above the upper limit of the reference range was <10%，and the reference range was validated successfully. Conclusions There are gender and age differences in Cys C levels in elders. The reference range of Cys C in healthy elders in Shanghai has been preliminarily established.

Key words: Cystatin C, Elder, Reference range, Shanghai