The Plasminogen Activator Inhibitor 1 4G/5G Polymorphism and the Risk of Alzheimer's Disease

Objective: The aim of this study was to determine whether plasminogen activator inhibitor 1 (PAI-1) is associated with the risk of Alzheimer's disease (AD) in Tunisian patients. Design and Methods: We analyzed the genotype and allele frequency distribution of the PAI-1 polymorphism in 60 Tunisian patients with AD and 120 healthy controls. Results: The results show a significantly increased risk of AD in carriers of the 4G/4G and 4G/5G genotypes versus the wild-type 5G/5G genotype (4G/4G: 28.33% in patients vs 10.0% in controls; P < 10(-3); OR = 8.78; 4G/5G: 55.0% in patients vs 38.33% in controls; OR = 4.45; P < 10(-3)). The 4G allele was also more frequently found in patients compared with controls; P < 10(-3); OR = 3.07. For all participants and by gender, homozygotic carriers (4G/4G) were at an increased risk of AD over heterozygotes and women were at an increased risk over their male genotype counterparts. The odds ratio for AD among 4G/4G carriers for any group was approximately twice that of heterozygotes in the same group. Women homozygotes ranked highest for AD risk (OR = 20.8) and, in fact, women heterozygotes (OR = 9.03) ranked higher for risk than male homozygotes (OR = 6.12). Conclusion: These preliminary exploratory results should be confirmed in a larger study.