CD4 and early-onset autosomal dominant Alzheimer disease: After adjusting for Alzheimer’s disease (IVW OR: 1.287; [95% CI 1.162 − 1.413]), liver iron content (IVW OR: 1.252; [95% CI 1.133 − 1.372]), sex hormone binding globulin levels (IVW OR: 1.259; [95% CI 1.130 − 1.387]) and naive CD4–CD8-T cell% T cell (OR: 1.264, [95% CI 1.137 − 1.390]), the risk of LTL on PCs was reduced, while adjusting for circulating leptin levels (IVW OR: 1.422; [95% CI 1.190 − 1.654]), did not induce a pronounced effect (Fig. 6A).