A longitudinal investigation of the relationships amongst antibody response to influenza vaccination, affect, and stress in the elderly

We examined the cross-sectional and longitudinal relationships amongst affect, stress exposure, and antibody (Ab) response to influenza inoculation in a healthy, elderly sample. We explored both efferent (CNS on immune activity) and afferent (immune activity on CNS function) pathways. Negative (NA) and positive (PA) affective states were examined in relation to Ab response, positing that high baseline NA (State, SNA, but not Trait, TNA) would predict reduced Ab response and that PA would predict enhanced response, and that the reduced Ab response in individuals displaying high baseline SNA would associate with decreases in NA. Moderator (for psychogenic and systemic stress) and mediator (systemic symptom reporting) tests were conducted to validate these relationships.The 152 (97 female, 55 male; age M=72.49, SD=6.32) participants were residents of a retirement community, who met medical exclusionary criteria and completed all three annual assessments (in 1992, 1993, and 1996). Participants were inoculated with trivalent influenza vaccine, and Ab titer was assayed two weeks post-inoculation via hemagglutinin inhibition assay.As hypothesized, TNA did not predict Ab response. Surprisingly, high baseline SNA predicted enhanced Ab response, which predicted decreased NA in a year- and strain-specific manner. Longitudinally, robust initial Ab response followed by steady decreases was associated with combinations of no change in one dimension of NA and decreases in the other. High PA only showed transient associations with increased Ab response. Stress did not act as a moderator, though systemic symptom reporting did mediate the relationship between Ab response and change in NA in 1996.Overall findings suggest a reconceptualization of initial NA. High levels of initial SNA did not predict impaired immunity, but instead robust response. Hence, instead of an aberrant affective state, high initial SNA likely indicates enhanced arousal, which returns to lower levels after threat ceases. This study also illustrates the complexities involved in investigating the relationship between health and immunity, and importantly sheds light on how varying temporal and antigenic variables may elicit differences. This study adds considerably to the body of work exploring the dynamic interplay between emotion, experience, aging, and physiological response to benign immune challenge