Behavioral-immunologic relationships in older men and women.

Serum immunoglobulin levels (IgG, IgA and IgM) and intellectual performance were examined in a group of fourteen elderly men (mean age 74.2) and twenty-three women (mean age 73.2) who reported that they were in good health. Significant negative Pearson product-moment correlations between performance and IgG and IgA emerged for men. Among women the relationship was not significant.