A higher anxiety state in old rats after social isolation is associated to an impairment of the immune response.

Social isolation is common in the elderly exerting negative effects on neuroimmunoendocrine communication. Nevertheless physiological responses to a stressful situation may vary according to diverse factors. This work studies the differences in the immune response of aged male rats socially isolated depending on the anxiety levels produced. Social isolation impaired certain immunological parameters, but a more anxious response to isolation was associated to global severe immunosuppression and greater oxidative state. Thus, responding anxiously to isolation may suppose a more potent risk of morbidity and mortality further than isolation and anxiety by themselves, particularly in elderly subjects.