Stress-Related Immune Changes in Middle-Aged and Older Women: 1-Year Consistency of Individual Differences

This study reviews prior research and reports longer-term consistency of stress-related immune variables in middle-aged and older women who performed mental math and speech tasks 2 times 1 year apart. Leukocyte subsets, mitogen-induced lymphocyte proliferation, and natural killer cell activity were measured at baseline, after tasks, and after 30-min recovery. Epstein-Barr virus (EBV) antibody titers were assessed at baseline. Pearson coefficients and standardized maximum-likelihood estimates of year-to-year covariances for leukocyte subsets and EBV titers showed moderately high to high baseline and posttask consistency and lower recovery consistency; consistency for other functional immune assays and reactivity scores for all variables was moderate to low. Results support longitudinal study of psychosocial context effects on tonic immune function and posttask scores. Key words: reproducibility, consistency, psychological stress, immune function, middle-aged women, older women Changes in immune parameters resulting from both acute and chronic stress are well documented (e.g., Glaser & Kiecolt-Glaser, 1994b). Clinical implications for these alterations are not certain, but researchers have postulated that they may mediate the relations between stress and various kinds of illness (e.g., Baum &amp