CD4 and atopic eczema: Besides that, the CD4+ T cell showed a risk causal effect on PA (OR = 3.92, p = 2.74 × 10–4) and the ratio of CD4+ T/CD8+ T also had a risk effect on atopic dermatitis (OR = 2.33, p = 4.70 × 10–2) (Fig. 4C).