GSTM1 and myocardial ischemia: In the analysis using both uric acid and Hb, compared with the reference group, the HRs for IHD were 1.37 (95% CI, 1.01–1.86) in the second group, 1.63 (95% CI, 1.21–2.21) in the third group, and 1.86 (95% CI, 1.30–2.67) in the fourth group after adjusting for IHD risk factors.