Association study of apolipoprotein E gene polymorphisms with geriatric depression

Abstract

Objective To examine the association between the polymorphisms of apolipoprotein E gene(APOE) and geriatric depression(GD), and then conduct an exploratory investigation to analyse whether the APOE polymorphisms would relate to the depressive syndrome severity, the cognitive function, or the level of serum lipid in patients. Methods Participants, including 120 GD patients and 120 normal controls were enrolled to detect the two single nucleotide polymorphisms of APOE, rs7412 and rs429358 using the technology of SNP site testing. The frequency differences of genotype and allele were compared between the two groups. Then the association between APOE polymorphisms and clinical or demographic data of patients were clarified . The relationship between clinical or demographic data, and the cognitive function of GD patients were investigated using the Logistic multiple regression analysis. Results The frequency of APOE genotype and allele showed no significant difference between the two groups(P>0.05). Patients carrying e4 allen had significantly lower total scores of Man-Machine System Engineering((22.38±2.22) vs (25.28±2.28), t=3.091, P<0.01) and higher levels of TC(t=2.225, P<0.05) and LDL(t=2.728, P<0.01) compared with those without e4 allen. The specific symptoms of patients carrying e4 allen were cognitive impairment(load 0.902) and retardant factors(load 0.695), while patients without e4 allen had characteristic symptoms of anxiety(load 0.990) and weight factors(load 0.864). Ranked by the effect power, the risk factors of cognitive impairment of GD patients are e4(b′=1.097) and then TCTC(b′= 0.401). Conclusions APOE may not modulate the susceptibility to GD. Patients carrying e4 allen have severer cognitive impairment and higher levels of serum lipid. The different genotypes may lead to different clinical symptoms. Key words: Geriatric depression; Apolipoprotein E; Polymorphisms; Cognitive function; Serum lipid