The incidence rates of non-AIDS composite events were significantly different between the cutoffs for CD4/CD8 ratio, with 11.42 per 100 PYS (95% CI 7.45–17.52) for current CD4/CD8 ratio < 0.3 and 2.23 per 100 PYS (1.77–2.81) for ratio > 0.45 (Table 3). Here, CD4 is linked to AIDS.