High serum adiponectin levels correlated with more severe WML (p = 0.013). Low BMI (p < 0.001), female sex (p = 0.025), and high WML scores (p = 0.039) were significant determinants of high serum adiponectin. HT (p = 0.032) and high adiponectin levels (p = 0.021) were independent risk factors for WML. Overall, we observed an association between serum adiponectin levels and WML severity in elderly people with cognitive decline. The gene discussed is ADIPOQ; the disease is Mental deterioration.