MORTALITY IN A COHORT OF MEN EXPRESSING THE GLUCOSE-6-PHOSPHATE-DEHYDROGENASE DEFICIENCY

The objective of this study was to test the hypothesis of a lower mort ality from cancer and cardiovascular diseases among men expressing glu cose-6-phosphate dehydrogenase (G6PD) deficiency. We designed a mortal ity study based on death certificates from January 1, 1982 through Dec ember 31, 1992 in a cohort of G6PD-deficient men. Cohort members were 1,756 men, identified as expressing the G6PD-deficient phenotype durin g a 1981 population screening of the G6PD polymorphism. The setting wa s the island of Sardinia, Italy. Outcome measures were cause-specific standardized mortality ratios (SMRs), which were computed as 100 times the observed/expected ratio, with the general Sardinian male populati on as the reference. Deaths from all causes were significantly less th an expected due to decreased SMRs for ischemic heart disease (SMR, 28; 95% confidence interval [CI], 10 to 62), cerebrovascular disease (SMR , 22; 95% CI, 6 to 55), and liver cirrhosis (SMR, 12; 95% CI, 0 to 66) , which explained 95.6% of the deficit in total mortality. All cancer mortality was close to the expectation, with a significant increase in the SMR for non-Hodgkin's lymphoma (SMR, 545; 95% CI, 147 to 1,395). A decrease in mortality from cardiovascular diseases was one of the st udy hypotheses, based on an earlier human report and experimental evid ence. However, selection bias is also a likely explanation. Further an alytic studies are warranted to confirm whether subjects expressing th e G6PD-deficient phenotype are protected against ischemic heart diseas e and cerebrovascular disease. This cohort study is consistent with mo re recent case-control studies in rejecting the hypothesis of a decrea sed cancer risk among G6PD-deficient subjects. The observed increase i n mortality from non-Hodgkin's lymphoma and decrease in mortality from liver cirrhosis were not previously reported. (C) 1998 by The America n Society of Hematology.