Loneliness, social network size, and immune response to influenza vaccination in college freshmen.
Level 3 - non-randomized controlled study
Prospective observational cohort study measuring psychological factors and subsequent vaccine antibody responses.
PubMed 15898866 · doi:10.1037/0278-6133.24.3.297
What was done
Assessed antibody response to influenza immunization in 83 healthy, first-semester university freshmen while monitoring loneliness, social network size, psychological stress, positive and negative affect, sleep quality and efficiency, and circulating cortisol levels throughout the semester.
What was found
No numerical values or effect sizes were reported in the abstract. Elevated loneliness and smaller social network size were independently associated with a poorer antibody response to one component of the vaccine, and participants with both high loneliness and small networks showed the lowest response. Loneliness was also linked to higher psychological stress, higher negative affect, lower positive affect, worse sleep quality and efficiency, and elevated cortisol. Only psychological stress met criteria for mediating the association between loneliness and antibody response; social network size was not associated with any of these potential mediators.
Why it matters
It provides evidence that subjective feelings of isolation and objective social network size independently relate to humoral immune responses following vaccination, suggesting distinct psychosocial pathways affect immune function.
Limits
The study had a small sample size (n = 83) limited to healthy first-semester college students. The design is observational, preventing definitive causal conclusions, and the reported immune impairment was limited to only one component of the vaccine. No numerical statistics or confidence intervals were provided in the abstract.
Cited by
- supports Loneliness causes spikes in bloodstream cortisol that compromise cardiovascular functioning and the immune system, leading to increased illness and shortened lifespan.