The multivariate logistic model analysis showed that smoking [odds ratio (OR), 6.774 (95% CI, 1.238–37.082); p = 0.027], increased Hamilton Depression scale (HAMD) score [OR, 1.074 (95% CI, 1.002–1.152); p = 0.045], hyperhomocysteinemia [OR, 2.815 (95% CI, 1.057–7.496); p = 0.038], elevated neuron-specific enolase (NSE) level [OR, 1.069 (95% CI, 1.007–1.135); p = 0.03] were independently correlated with higher risk of SD in AE patients. The gene discussed is ENO2; the disease is major depressive disorder.