CD4 and Alzheimer disease: Comparing to using CT alone, combined with AD (MD = 1.34, 95% CI [1.06–1.70]), HQ (MD = 1.19, 95% CI [0.96–1.47]), CKS (MD = 1.35, 95% CI [0.97–1.88]), on the basis of chemotherapy can improve CD4+/CD8+ decline in patients and make the difference between groups statistically significant.