Multivariate logistic analysis identified smoking (OR ═ 1.385, 95% CI ═ 1.229–1.671; P ═ 0.006), GOLD (OR ═ 1.558, 95% CI ═ 1.394–2.463; P < 0.001), hypertension (OR ═ 1.272, 95% CI ═ 1.097–1.459; P ═ 0.017), serum HIF-1α (OR ═ 1.058, 95% CI ═ 1.015–1.236; P ═ 0.026), plasma ET-1 (OR ═ 1.187, 95% CI ═ 1.048–1.334; P ═ 0.008), and NO (OR ═ 1.124, 95% CI ═ 1.065–1.409; P ═ 0.015) as independent risk factors for AECOPD (Table 3). The gene discussed is EDN1; the disease is Hypertension.