CD4 and CD8 counts are associated with interactions of gender and psychosocial stress

Objective: This study examined relationships of gender, psychosocial stress/distress (caregiving, hassles, depressed mood), and the relative percentage and absolute cell counts of CD4 and CD8 cells in two samples of older adults (mean age = 69.4)-spouse caregivers of persons with Alzheimer's disease (N = 78) and age- and gender-matched spouses of nondemented controls (N = 72). Methods: Counts and percentages of CD4 and CD8 cells and psychosocial variables were assessed twice (Time 1, Time 2) over a 15- to 18-month period. Several covariates were examined in the analyses, including body mass index (BMI), medication use, alcohol use, exercise, and illness history. Results: Caregiver men had fewer CD4 cell counts at Times 1 and 2 than did control men (p <.05). At Times 1 and 2, both CD8 cell counts and percentages were positively associated with hassles in men (p, <.05), but not in women. Although interactions of hassles and gender were present for CD8 percentages at both times, interactions and main effects were not present for CD4 percentages at either time. When the ratio of CD4 to CD8 levels was analyzed, hassles by gender interactions were present at both Times 1 and 2-hassles were negatively associated with the CD4/CD8 ratio in men (p <.05), but unrelated in women. From Time 1 to Time 2, change analyses showed that increases in hassles scores were associated with decreases in CD4 counts (p <.05), whereas increases in Hamilton Depression Scores were related to increases in both CD8 counts and percentages (p <.05). Conclusion: Caregiver status, hassles, and depressed mood had cross-sectional and/or longitudinal associations with CD4 and CD8 counts, but such relationships occurred primarily in men. Moreover, absolute cell counts were more related to psychosocial factors than were percentages.