Correspondence Subjects expressing the

glucose-6-phosphate dehydrogenase deficient phenotype experience a lower cardiovascular mortality Sir, In a recent mortality follow-up study of lead smelters in southwestern Sardinia, Italy, whose glucose-6-phosphate dehydrogenase (G6PD) phenotype was part of the pre-employment screening program, workers expressing the G6PD deficient (G6PD) phenotype showed a substantial reduction in cardio-vascular mortality.1 The same result was previously reported in a follow-up study of G6PD subjects who voluntarily participated in a population screen-ing,2 as well as in a US cross-sectional study of hospitalized patients.3 Interpretation of those earlie