LPL and Alzheimer disease: Our subgroup meta-analyses indicated that A2M V1000I was a risk factor of AD in Italian population among 171 cases and 212 controls (OR = 1.37, 95% CI = 1.07–1.75, P = 0.01), and LPL Ser447Ter polymorphism was likely to be a protective factor of AD in Northern-American population (OR = 0.56, 95% CI = 0.35–0.91, P = 0.02, Figure S2).