GSTM1 and angina pectoris: Furthermore, we adjusted for potential confounding variables, including age, gender, race, education level, marital status, smoking status, drinking status, hypertension, high cholesterol, CHD, angina, heart attack, stroke, and diabetes status, PIR, PA, SBP, DBP, BUN, serum creatinine, eGFR, serum uric acid, HbA1c, Hb, TC, LDL-C, and waist circumference to reduce the impact of confounding factors and obtain more reliable results.