Effects of the association between APOE rs405509 polymorphisms and gene-environment interactions on hand grip strength among middle-aged and elderly people in a rural population in southern China

Background Hand grip strength is a complex phenotype. The current study aimed to identify the effects of the association between APOE rs405509 polymorphisms and gene-environment interactions on hand grip strength among middle-aged and elderly people in a rural population in Gongcheng, southern China. Methods APOE rs405509 polymorphisms in 1724 participants (695 men and 1029 women, aged 45–97 years old) were genotyped using the Sequenom MassARRAY platform. Statistical analysis was conducted using SPSS 21.0 and Plink 1.90. Results The APOE rs405509 G allele was associated with lower hand grip strength in all participants (β = −1.04, P value <0.001), and the correlation seemed to be even stronger among women. A significant gene-environment interaction was observed between APOE rs405509 and smoking, especially in men. The hand grip strength of male smokers carrying the GG genotype was significantly higher than that of nonsmokers ( P value = 0.004). Conclusions APOE rs405509 polymorphisms might be genetic factors that affect hand grip strength in a rural population in Gongcheng, southern China. The APOE rs405509-smoking interaction has an impact on hand grip strength.