Heliyon · Jan 4, 2024

Serum cystatin C as a biomarker to predict all-cause mortality in geriatrics hip fracture

By Zhang BF, Liu L, Xu K et al.

BACKGROUND: Cystatin C, a low-molecular-weight protein, belongs to cysteine protease inhibitors produced primarily by nucleated cells. Its serum concentration, independent of sex, age, or muscle mass, is a good predictor of renal dysfunction in older adults. This study evaluated the association between all-cause mortality and preoperative cystatin C levels in hip fractures. MATERIALS AND METHODS: Data describing the demographic and clinical characteristics of the patients were gathered specifically from older individuals who had suffered hip fractures. The study used linear and non-linear multivariate Cox regression models to investigate the association between preoperative cystatin C levels and mortality. The analyses were conducted using the R and EmpowerStats software. RESULTS: In total, two thousand three hundred and ninety-four patients were included in this study. A total of 790 patients (33 %) died of all causes. The mean follow-up was 37.62 months. The preoperative cystatin C was 0.91 ± 0.41 mg/L. Linear multivariate Cox regression analysis revealed a significant association between preoperative cystatin C level and death, with a hazard ratio (HR) of 2.19 (95 % confidence interval [CI]: 1.72-2.79, P < 0.0001). Nevertheless, the correlation between the variables was inconsistent. A cystatin C concentration of 1.62 mg/L marked a significant change in the non-linear relationship. A preoperative cystatin C level below 1.62 mg/L was found to be significantly linked with an increased risk of mortality (HR = 2.60, 95 % CI: 1.92-3.52, P < 0.0001). The mortality reached its highest point when the preoperative cystatin C level was greater than 1.62 mg/L. After that, the mortality risk did not increase further (HR = 1.54, 95 % CI: 0.98-2.42, P = 0.0588). The non-linear relationship remained consistent in the propensity score-matching sensitive analysis. CONCLUSIONS: The study found a non-linear relationship between preoperative cystatin C levels and mortality in geriatric hip fractures. This suggests that preoperative cystatin C can be used as a predictor of the risk of death. The registration number is ChiCTR2200057323.

doi.org/10.1016/j.heliyon.2024.e24037 Open access PubMed 38283240 Biomarkers