The concentrations of serum cytokines such as tumor necrosis factor-α, interleukin (IL-1, IL-6, and IL-17), and C-reactive protein were higher in patients with sleep disorders than in patients with good sleep, which could increase the hypothalamus-hypothesis-adrenal axis stress response, elevate blood pressure, and lead to chronic inflammation [20, 23, 24], all of which could increase the risk of CHD. Here, IL6 is linked to sleep disorder.