GSTM1 and aortic stenosis: Our findings are that: 1) AS patients older than 75 years of age have higher plasma TGF-β1 values and lower Hb levels than AS patients younger than 75 years of age or patient control subjects in either age group; and 2) there is a negative correlation between plasma TGF-β1 values and Hb levels in older, but not younger, AS patients.