GSTM1 and Hypertension: After controlling for age, BMI, rhinitis, hypertension, smoking, glucose level, HbA1C, hemoglobin (Hb), creatinine (Cr), total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDLC), and high-density lipoprotein (HDL), we found that TNF-α was negatively associated with the mean SpO2 (r = −0.258, P = 0.043; Figure 3).