| Objective To explore the diagnostic value of calprotectin and cytokine like protein 1 (CYTL1) in elderly knee osteoarthritis (KOA). Methods A total of 65 elderly KOA patients diagnosed and treated in our hospital from August 2019 to August 2023 were collected as the study group. Sixty-five patients who underwent health examination in our hospital were as the control group. Pearson method was used for analyzing correlation. Logistic regression was applied to analyze the factors affecting the occurrence of elderly KOA. Receiver operating characteristic (ROC) curve was applied to analyze the diagnostic value of serum calprotectin and CYTL1 levels for the occurrence of elderly KOA. Results The serum levels of calprotectin, TNF-α, CRP, and percentage of B cells in the study group were obviously higher than those in the control group (P<0.05). The levels of CYTL1, IL-4, percentage of CD3+T cells, percentage of CD4+T cells, and percentage of CD8+T cells in the control group were obviously lower than those in the control group (P<0.05). As the condition of elderly KOA patients worsened, serum calprotectin level obviously increased (P<0.05), while CYTL1 level obviously decreased (P<0.05). There was a negative correlation between serum calprotectin level and CYTL1 level in elderly KOA patients (r= – 0.672, P<0.05). Calprotectin, TNF-α, and percentage of B cells were risk factors affecting the occurrence of elderly KOA patients (P<0.05). CYTL1 and IL-4 were protective factors affecting the occurrence of elderly KOA patients (P<0.05). The area under the curve (AUC) of serum calprotectin, CYTL1, and their combination in the diagnosis of elderly KOA was 0.865, 0.850, and 0.926, respectively. The combination of the two was obviously higher than that of calprotectin and CYTL1 alone (Zcombination-calprotectin=2.018, Zcombination-CYTL1=2.514, P<0.05). Conclusion The serum calprotectin level increases and CYTL1 level decreases in elderly patients with KOA, which has clinical value for the diagnosis of elderly KOA. |