Smoking and Aldosterone Synthase Polymorphism

To the Editor: Hautanen and colleagues1 claim that dyslipidemic middle-aged men from the Helsinki Heart Study with the aldosterone synthase (CYP11B2, –344T/C) CC genotype who smoked were ≈5 times more likely to suffer a nonfatal myocardial infarction than nonsmokers of the same genotype during a follow-up period of 8.5 years. I think that this finding is likely to be spurious and result from artefactual control matching. The cases included 75% of patients who had a nonfatal myocardial infarction; those who suffered cardiac death comprised one-fifth of the total cardiac event population and were excluded from analyses. This selection bias might have accounted for the relatively low frequency of the T allele in this study (0.48) compared with other reports (0.54 to 0.60).2 3 Whether subjects with the T allele were more likely to suffer cardiac death could not be known. Importantly, there were more smokers across the genotype …