Abstract
Depression is a common mental health problem in older adults, but its cause remains unclear. Selenium is an essential micronutrient and a powerful antioxidant in the brain and nervous system. Several recent studies have reported a relationship between selenium levels and depression. This study aimed to investigate the relationship between 4 genes co-associated with selenium and geriatric depression. 1486 participants were included in this study from 5 communities in Ningxia Hui Autonomous Region during 2013 to 2016 in a health examination program for urban and rural residents. Polymorphisms of 4 selenium-related genes were analyzed in 1266 healthy volunteers and 220 patients with depression. The genotyping of rs2830072, rs2030324, rs6265, rs11136000, rs7982, rs10510412, rs1801282, rs1151999, rs17793951, rs709149, rs709154, and rs4135263 were performed by Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS) technology. The analysis of selenium-related genes showed that there were significant differences between depression and controls for allele and genotype frequencies of peroxisome proliferator activated receptor gamma (PPARG) rs10510412, rs709149, and rs709154 (all P < .05). In this study, when adjusting for age, sex, marital status, education, and alcohol consumption, results showed that rs709149 and rs709154 were still significantly correlated with geriatric depression in the codominant, dominant, overdominant, and log-additive models. Logistic regression analysis showed that rs709149 AG or GG gene carriers were 1.630 and 1.746 times more susceptible to depression than AA gene carriers (95% CI = 1.042-2.549; 1.207-2.526). The results of this study suggest that the rs709149 polymorphism of the selenium-related gene PPARG is a genetic risk factor for depression in older adults.