The pooled data from continuous data showed that CRP levels were significantly associated with delirium (OR: 1.10, 95% CI: 1.01-1.20, <i>p</i> = 0.030); and the pooled data from categorical data revealed that high CRP levels increased the risk of delirium (OR: 2.66, 95% CI: 2.00-3.53, <i>p</i> < 0.001). This evidence concerns the gene CRP and delirium.