ABO blood type and longevity.

To assess the observation that blood type B might be a marker for longevity, we reviewed the records and determined the ABO blood types of all patients who died in our hospital in 2004. Age was stratified by decade of death, and linear regressions were calculated by ABO percentage. ABO survival curves were compared. In 2004, 906 patients died; 35 were excluded (stillborn infants). Of the remaining 871 patients, ABO types were available for 772 (88.6%). The percentage of patients with group B blood declined with age (P < .01). None of the other blood type percentages had a statistically significant increase or decrease. The group B survival curve was statistically worse than non-B groups (P ≤ .01); there were no differences in survival among groups A, O, and AB (P =.47). In our patient population, the percentage of patients with group B blood declines with age. The survival curve in group B was worse than that in groups A, O, and AB. These findings suggest that in our patient population, blood group B is not a marker for longevity but may be a marker for earlier death.