The role of minor health status in secretory immunoglobulin-A (S-IgA) reactivity to acute and cumulative acute stress

Secretory immunoglobulin-A (S-IgA) provides a first line of defence against antigens in the mucosa and is sensitive to changes in psychological stress. Stress plays an important role in susceptibility to infections of the mucosa and as such S-IgA is a potential moderator between stress and ill-health. The effects of an acute laboratory stressor upon S-IgA reactivity were assessed in healthy students classified as being in either good or poor health with regards to 4 clusters of minor ill-health (total ill-health, stress related ill-health indicators and psychological). In 2 experiments students were exposed to the same stressor on 2 occasions (24 hours apart) and in a cumulative acute stress paradigm, comprising 3 cycles of stress-relaxation periods. Perceived task demands were also recorded following each stressor exposure. The current stressor elicited increases in S-IgA reactivity following each stress exposure (mean increase=12.9μg/min). Further, students classified as in poor health demonstrated lower S-IgA reactivity than those in good health. These discrepancies became most pronounced following cumulative stress, where those in good health demonstrated positive S-IgA reactivity to each of the 3 stressors (1=22.74μg/min, 2=19.3μg/min, 3=22.31μg/min), and those in poor health demonstrated significant progressive reductions in S-IgA with each subsequent stressor (1=8.02μg/min, 2=-8.04μg/min, 3=-9.76μg/min). Those in poor health also reported the stressor to be more demanding (p